Partly Substituting Whey for Collagen Peptide Supplementation Improves Neither Indices of Muscle Damage Nor Recovery of Functional Capacity During Eccentric Exercise Training in Fit Males

Click name to view affiliation

Ruben Robberechts Exercise Physiology Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium

Search for other papers by Ruben Robberechts in
Current site
Google Scholar
PubMed
Close
https://orcid.org/0000-0002-5715-994X
,
Chiel Poffé Exercise Physiology Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium

Search for other papers by Chiel Poffé in
Current site
Google Scholar
PubMed
Close
https://orcid.org/0000-0002-8085-3075
,
Noémie Ampe Department of Physical and Rehabilitation Medicine, University Hospitals Leuven, Leuven, Belgium

Search for other papers by Noémie Ampe in
Current site
Google Scholar
PubMed
Close
,
Stijn Bogaerts Department of Physical and Rehabilitation Medicine, University Hospitals Leuven, Leuven, Belgium
Department of Development & Regeneration, KU Leuven, Leuven, Belgium

Search for other papers by Stijn Bogaerts in
Current site
Google Scholar
PubMed
Close
https://orcid.org/0000-0001-5708-2439
, and
Peter Hespel Department of Movement Sciences, KU Leuven, Leuven, Belgium

Search for other papers by Peter Hespel in
Current site
Google Scholar
PubMed
Close
https://orcid.org/0000-0003-1283-2229 *
Free access

Previous studies showed that collagen peptide supplementation along with resistance exercise enhance muscular recovery and function. Yet, the efficacy of collagen peptide supplementation in addition to standard nutritional practices in athletes remains unclear. Therefore, the objective of the study was to compare the effects of combined collagen peptide (20 g) and whey protein (25 g) supplementation with a similar daily protein dose (45 g) of whey protein alone on indices of muscle damage and recovery of muscular performance during eccentric exercise training. Young fit males participated in a 3-week training period involving unilateral eccentric exercises for the knee extensors. According to a double-blind, randomized, parallel-group design, before and after training, they received either whey protein (n = 11) or whey protein + collagen peptides (n = 11). Forty-eight hours after the first training session, maximal voluntary isometric and dynamic contraction of the knee extensors were transiently impaired by ∼10% (Ptime < .001) in whey protein and whey protein + collagen peptides, while creatine kinase levels were doubled in both groups (Ptime < .01). Furthermore, the training intervention improved countermovement jump performance and maximal voluntary dynamic contraction by respectively 8% and 10% (Ptime < .01) and increased serum procollagen type 1N-terminal peptide concentration by 10% (Ptime < .01). However, no differences were found for any of the outcomes between whey and whey protein + collagen peptides. In conclusion, substituting a portion of whey protein for collagen peptide, within a similar total protein dose, improved neither indices of eccentric muscle damage nor functional outcomes during eccentric training.

Collagen is the primary component of connective tissue and largely determines the elasticity and stiffness of musculoskeletal tissues. As it is responsible for the transmission of forces from myofibrillar proteins, a well-developed structural integrity of the connective tissue of muscle and tendon is crucial for maximizing muscle force and power output (Kjær, 2004).

While mechanical loading is the primary stimulus for connective tissue remodeling, there is increasing interest in the potential role of nutrition in connective tissue health. Several recent studies have addressed the effects of dietary collagen supplementation in the form of gelatin or collagen peptides on musculoskeletal repair and remodeling postexercise. Studies showed that collagen-derived supplements following an acute eccentric exercise bout attenuated creatine kinase increase (Lopez et al., 2015) and accelerated recovery of jump performance (Clifford et al., 2019). In addition, long-term collagen peptide supplementation in conjunction with resistance training increased fat-free mass (Balshaw et al., 2022; Kirmse et al., 2019; Zdzieblik et al., 2015, 2021), muscle strength (Balshaw et al., 2022; Jendricke et al., 2019; Zdzieblik et al., 2015), rate of force development (Lis et al., 2022), and endurance performance (Jendricke et al., 2020).

Importantly, the aforementioned studies all compared the effects of collagen peptide supplementation with a biologically inactive nonprotein placebo. Given the evidence that postexercise protein intake stimulates muscle protein synthesis and facilitates muscle repair and functional recovery (Buckley et al., 2010; Devries & Phillips, 2015; Koopman et al., 2007), such approach increases the likelihood of favorable outcomes. Thus, data so obtained do not provide evidence that collagen-derived supplements are superior to prevailing nutritional practices, for instance, with regard to postexercise whey protein intake in athletic populations. Moreover, while some studies have reported an increase in intramuscular connective tissue rates with casein (Holwerda et al., 2021) or whey protein (Holm et al., 2017), others have found no such effect (Aussieker et al., 2022; Oikawa, Kamal, et al., 2020).

Therefore, it is essential to balance the effects of collagen supplementation against the effects of recommended whey protein intake. Unfortunately, to date, only a few studies have used whey protein supplementation or another leucine-rich protein supplement as the appropriate control condition. One study found that whey protein supplementation led to a greater increase in muscle size compared to leucine-matched collagen peptide supplementation over a 10-week training period. But muscle strength and power changes were similar between the groups (Jacinto et al., 2022). The superior efficacy of whey protein over collagen peptide supplementation in terms of anabolic response is further supported by the observation that whey protein, but not collagen peptides, increased myofibrillar protein synthesis following resistance training in both young volunteers (Aussieker et al., 2022; Oikawa, et al., 2020) and older individuals on either a normal (Oikawa, et al., 2020) or a low-energy diet (Oikawa et al., 2018).

In this context, it is of interest that collagen peptides and whey protein have distinct amino acid profiles, which may contribute to potentially different effects on musculoskeletal tissue remodeling. Whey protein contains a high fraction of all essential amino acids, including leucine, which is ideal to stimulate myofibrillar protein synthesis (Phillips et al., 2009). But there is also evidence from one study that whey protein supplementation may also facilitate tendon hypertrophy in response to strength training in humans (Farup et al., 2014). However, whether this effect was caused by the whey protein intake per se, or rather indirectly resulted from the higher degree of muscle hypertrophy is unclear (Baar, 2017). Conversely, the nonessential amino acids glycine, hydroxyproline, and proline are more abundant in collagen peptides. Proline and hydroxyproline did not appear to limit collagen synthesis (de Paz-Lugo et al., 2018). In addition, also whey protein contains significant amounts of proline. In contrast, the glycine fraction is marginal in whey, versus abundant in collagen peptides (Oikawa, Kamal, et al., 2020). Glycine has been termed a semiessential amino acid (de Paz-Lugo et al., 2018; Meléndez-Hevia et al., 2009) because the supply via a normal mixed diet appeared insufficient to maximally stimulate collagen synthesis in resting individuals (Meléndez-Hevia et al., 2009). However, more recent studies found collagen peptides supplementation does not elevate collagen synthesis in human muscles following resistance exercise (Aussieker et al., 2022; Oikawa et al., 2020). Yet collagen peptide supplementation still could beneficially impact collagen synthesis in tissues other than muscle, such as tendons and ligaments. Support for such rationale comes from a study by Shaw et al. (2017) which demonstrated that incubation of in vitro engineered ligaments with serum obtained from subjects who ingested gelatin supplements before an eccentric exercise bout resulted in higher collagen content and improved mechanical properties. Furthermore, treatment with a collagen peptide solution increased collagen content and cross-linking activity in osteoblasts (Yamada et al., 2013). Despite that these effects have not yet been demonstrated in humans, it seems plausible that increasing postexercise glycine supply by collagen peptide intake could increase collagen synthesis and cross-linking in tissues other than skeletal muscles themselves.

Eccentric exercise increases both myofibrillar and muscle and tendon connective tissue turnover rates (Kjær, 2004). Given their different amino acid compositions, it is reasonable to postulate that combined supplementation of whey protein and collagen peptide following eccentric exercise—each potentially targeting a different component of the musculoskeletal system—may enhance muscular recovery and improve functional outcomes more than collagen peptide or whey protein supplementation alone. Accordingly, collagen peptide supplementation attenuated muscle damage and improved muscle force-generating capacity following an eccentric exercise bout (Clifford et al., 2019; Lis et al., 2022; Lopez et al., 2015).

Against the above background, the current study aimed to compare the effects of collagen peptide plus whey protein supplementation with a similar total protein dose, delivered in the form of whey protein alone, on eccentric exercise-induced muscle damage and acute recovery of muscular performance. We hypothesize that for a given total protein dose, a combination of whey protein and collagen peptide is superior to whey protein alone in stimulating recovery of muscle force-generating capacity following acute and short-term eccentric exercise.

Methods

Subjects and Ethical Approval

Twenty-two healthy male subjects who met the inclusion criteria were recruited for voluntary participation in the study (for subject characteristics, see Table 1). An a priori sample size calculation was conducted using G*Power (version 3.1.9.7) based on a Cohen’s f effect size of 0.275 obtained from two previous studies that used a similar research design and collagen peptide dosing strategy as in the current study (Clifford et al., 2019; Lis et al., 2022). To calculate the sample size, we used a statistical power of 0.8 and a probability level of .05. This yielded a total required sample size of 20 subjects. To account for an anticipated dropout rate of 10%, a total of 22 subjects were eventually enrolled in the study. Before signing the informed consent form, the subjects were informed in detail about the study protocol and the potential risks associated with participation. All subjects were nonvegetarians, nonsmokers, had a body mass index between 18.5 and 25 kg/m2, and had no injuries or medical conditions that would contraindicate strenuous strength or plyometric training. Subjects who had consumed whey protein, casein, or branched-chain amino acid supplements from 1 month prior to the start of the study or had regularly performed strength and/or plyometric training were excluded from participation. Prior to enrolment in the study, all subjects were examined by a qualified physician. The study was conducted in accordance with the Declaration of Helsinki, preapproved by the Ethics Committee of UZ Leuven (B3222020000176), and registered retrospectively in a clinical trial database (ClinicalTrials.gov—NCT05425407). Data were collected at the Exercise Physiology Research Group of KU Leuven between March and May 2021.

Table 1

Baseline Subject Characteristics

WWCP
Age (years)24.4 ± 2.420.8 ± 1.9
Height (m)1.81 ± 0.061.80 ± 0.05
Body mass (kg)74.3 ± 6.673.8 ± 5.6
BMI (kg/m2)22.7 ± 1.422.8 ± 1.4
Sports participation (hr/week)4.18 ± 1.193.41 ± 1.41
CMJ jump height (cm)33.9 ± 6.736.1 ± 5.8
MVCiso torque (N·m)241 ± 34227 ± 45
MVCdyn torque (N·m)76.2 ± 6.575.1 ± 12.2
25-RM (kg)21.6 ± 3.920.3 ± 5.2

Note. Data are presented as mean ± SD and represent baseline characteristics of the subjects enrolled in the W protein (n = 11) and the WCP group (n = 11). CMJ = counter movement jump; MVCiso = maximal voluntary isometric knee extension torque; MVCdyn = maximal voluntary dynamic knee extension torque; 25-RM = 25 repetitions maximum; BMI = body mass index; W = whey protein; WCP = whey protein + collagen peptide supplements.

Preliminary Testing and Subject Randomization

Two weeks prior to the start of the intervention period, the subjects participated in two familiarization sessions 2 days apart to habituate to the exercise testing protocol. This involved a dynamic maximal voluntary contraction test (MVCdyn), an isometric maximal voluntary contraction test (MVCiso), a countermovement jump test (CMJ), as well as a 25-repetition maximum test (25-RM) on a knee extension device. The procedures for the CMJ, MVCdyn, and MVCiso were identical to that used on the experimental days (see “Evaluation of Functional Performance” section). For the 25-RM assessment, subjects started with a 12.5 kg load. After successful completion of 25 repetitions, 0.5 or 1 kg was added until failure. Five minutes of passive recovery were provided between attempts. In the second familiarization session, the subjects started with their 25-RM of the first session. Subsequently, 0.5 kg was added with 5-min passive recovery episodes in between and until failure. The amplitude of the knee extension was limited from 75° to 175° knee angle (180° = fully extended leg), and a visual metronome set the execution rate to 0.5 Hz. Prior to randomization, the subjects were pair-matched based on body mass index, CMJ, MVCiso, and 25-RM. Randomization was performed by a researcher who was otherwise not involved in the study.

General Study Design

The study was conducted according to a double-blind, randomized, parallel-group design. The intervention period involved a pretest (PRE) and a posttest (POST), which were interspersed by a 1-week run-in period and a 3-week training period (Figure 1). The training period aimed to specifically overload the knee extensor muscles. In addition, to investigate the acute effects of a single training session, an experimental session (TR1+48hr) was also scheduled 48 hr after the first session. During the run-in week and the training period, the subjects received either a total daily dose of 20 g of collagen peptide and 25 g of whey protein (WCP, n = 11) or an equivalent total protein dose (45 g) of only whey protein (W, n = 11). The run-in week served to habituate the subjects to the supplementation protocol and to ensure adequate protein availability by the start of the training period. To allow evaluation of the effects of supplementation in the absence or presence of overload training, all exercises during the training period were performed with the dominant leg only, the contralateral leg serving as the nonexercised control leg. The primary outcomes of the study were the change in CMJ and MVCiso performance of the trained leg.

Figure 1
Figure 1

—Overview of the study design. Note. The subjects participated in a 3-week resistance training program aiming to specifically overload the knee extensor muscles by eccentric contractions. During the intervention period, the subjects received either whey supplements (W, n = 11) or whey protein + collagen peptide supplements (WCP, n = 11) according to a double-blind and randomized study design. D = day; TR = training session; TR1+48h, 48 hr after training session 1.

Citation: International Journal of Sport Nutrition and Exercise Metabolism 34, 2; 10.1123/ijsnem.2023-0070

Supplementation

Whey protein sachets contained either 15 or 30 g whey protein isolate (84% of amino acids, 6d Sports Nutrition). Whey protein + collagen peptide sachets contained either 10 g collagen peptides (100% of amino acids, Collagen Peptan®, Rousselot BV) mixed with 5 g whey protein isolate (84% of amino acids, 6d Sports Nutrition) or 10 g collagen peptide mixed with 20 g whey protein isolate. Whey protein powder contained 163.8 kcal/day, and whey protein + collagen peptide powder contained 168.5 kcal/day. Both supplements were similar in flavor (vanilla) and appearance. The amino acid content of the two protein supplements is provided in Table 2. The supplementation started in the run-in week and was continued till the end of the training program. During the run-in week and on rest days during the training period, the subjects consumed a 15 g supplement immediately before breakfast and a 30 g supplement 2 hr after breakfast. On training days, the 15 g supplements were ingested 1 hr before the start of the training session and the 30 g supplements immediately after the training session. Administration of a preexercise supplement was based on a previous protocol published by Shaw et al. (2017). Administration of supplements immediate postexercise was based on the prevailing recommendations with regard to protein supplementation after exercise (Phillips & van Loon, 2011). All supplements were dissolved in 300 ml of water. Adherence was verified through on-site intake of the postexercise supplements. To control supplement adherence at home, subjects were requested to return the empty sachets upon arrival for the next training session.

Table 2

Amino Acid Composition of the Whey and Whey + Collagen Peptide Supplements

WWCP
Alanine1.82.8
Arginine0.72.0
Aspartic acid4.13.4
Cysteine1.00.0
Glutamic acid6.45.6
Glycine0.64.7
Histidine0.60.6
Hydroxylysine0.00.2
Hydroxyproline0.02.2
Isoleucine2.31.6
Leucine3.82.7
Lysine3.52.6
Methionine0.80.6
Phenylalanine1.11.0
Proline2.13.8
Serine1.71.6
Threonine2.61.8
Tyrosine1.00.6
Valine2.11.7
Tryptophan1.60.0

Note. Values are grams of amino acid supplied by the daily 45 g dose of protein supplements. W = whey protein supplements; WCP = whey protein + collagen peptide supplements.

Training Intervention

See Table 3 for a detailed overview of the training program. The training period involved 17 training sessions (TR1–TR17). TR1 was followed by a rest day. From Day 3, the subjects participated in six weekly sessions. Each session consisted of three exercises: unilateral knee extensions, inclined one-leg squats, and one-leg drop jumps in this order. All sessions were supervised by the investigators. Unilateral knee extensions were executed on a knee extension device limiting the movement range from 75° to 175° knee angle. One-leg squats were executed from 90° to 180° knee angle on a 30° downhill inclination platform, and one-leg drop jumps were performed from a 40 cm platform from TR1 to TR8 and from a 60 cm platform from TR9 to TR17. During the drop jumps, the subjects were instructed to sink to a 75° knee angle, followed by an all-out one-leg vertical jump. The execution rate for all exercises was fixed by a metronome. Subjects rested for 2 min between sets and exercises. For each exercise, the workload was gradually increased during the training period by adjusting both the number of sets and the execution rate. In addition, before the start of TR6 and TR12, 25-RM for the knee extensions was tested to adjust the workload in Weeks 2 and 3 of the training intervention. Whenever subjects were unable to complete the training session according to the protocol due to either fatigue or pain, the workload was reduced, and the actual work done was logged in a training diary.

Table 3

Overview of the Training Program

ExerciseLoadSetsRepetitions
Knee extensions
 TR1–TR875% of 25-RM520
 TR9–TR1370% of 25-RM720
 TR14–TR1770% of 25-RM820
One-leg squats
 TR1–TR830°520
 TR9–TR1330°720
 TR14–TR1730°1020
Drop jumps
 TR1–TR840 cm520
 TR9–TR1360 cm720
 TR14–TR1760 cm1020

Note. The subjects participated in a 3-week resistance training program aiming to specifically overload the knee extensor muscles by eccentric contractions. During the intervention period, the subjects received either whey protein supplements (n = 11) or whey protein + collagen peptide supplements (n = 11) according to a double-blind and randomized study design. TR = training session; 25-RM = 25 repetitions maximum.

Evaluation of Functional Performance

Muscular functional capacity was evaluated at PRE, TR1+48hr, and POST. Before CMJ, the subjects warmed up for 5 min on a cycle ergometer (Avantronic Cyclus II) at 100 W. Subsequently, they performed five barefoot CMJs interspersed by 1-min rest intervals on a contact mat (Smartjump, Fusionsport). Subjects started in the upright position with hands on the loins, and thereafter they squatted to a 90° knee angle before jumping all-out while maintaining full knee extension till landing. The average of the three best attempts was used for further analyses. MVCdyn and MVCiso of the knee extensors were assessed bilaterally in the seated position on a motor-driven isokinetic dynamometer (Hespel et al., 2001). To determine MVCdyn, the subjects performed a series of 30 unilateral maximal dynamic voluntary knee extensions from 105° to 175° knee angle at 180°/s angular velocity. After each contraction, the leg was passively returned (180°/s) to the starting position, and thereafter the next contraction was immediately started. Torque was digitized on a computer (250 Hz), and MVCdyn was defined as the average of the peak torques over the series of 30 knee extensions. Following a 1-min rest, the subjects performed five maximal voluntary isometric contractions (3 s) at a knee angle of 135°, interspersed by 1-min rest intervals. MVCiso was obtained from the static torque curve, and the average of the three best attempts was used for further analyses. After completion of the testing of the trained leg, the same procedures were repeated for the contralateral leg. The functional tests were always supervised by the same investigator.

Muscular Pain Perception

Muscular pain in the exercise leg was assessed on an 11-point visual analog scale (ranging from 0 to 10) immediately after the drop jumps following TR1, TR2, and TR17.

Dietary Control

Nutritional intake was monitored via an online dietary platform (Mijn Eetmeter, Stichting Voedingscentrum Nederland; https://mijn.voedingscentrum.nl). Food diaries were obtained during the last 3 days of the run-in week and during the final 3 days of the training period to identify possible nutritional variations between the groups.

Blood Sampling

Venous blood samples were collected from an arm vein 1 hr after breakfast at PRE, TR1+48hr, and POST. Blood samples were drawn in two vacuum tubes containing either lithium heparin or Silica Clot Activator and subsequently centrifuged at 1,500 rpm for 10 min at 4 °C. The supernatant plasma or serum was stored at −20 °C for later analyses. Serum total creatine kinase and procollagen type I N-terminal propeptide (P1NP) concentrations were determined as a singlet using an electrochemiluminescence immunoassay and a colorimetric assay, respectively. Furthermore, a commercially available high-sensitivity ELISA kit was used to assay serum interleukin 6 (IL-6) (HS600C, R & D systems) in duplicate as a marker of inflammation.

Statistical Analyses

All statistical analyses were performed in GraphPad Prism (version 9.0.1). A two-tailed paired t test was used to assess baseline differences between groups. Two-way analysis of variance repeated measures (Group × Time) was used to analyze differences over multiple time points. If the assumption of sphericity was violated (Mauchly’s test), the Geisser–Greenhouse correction was applied. In case of a significant time (Ptime) or interaction (Pint) effect (p < .05) was detected, the Šídák multiple comparison test was used for post hoc analyses. When a significant time effect was observed, post hoc testing was performed for the total group of subjects between the different time points. Effect size values were calculated as partial η squared (ηp2) and interpreted using thresholds of <.01, <.06, <.14, and ≥.14 for respectively negligible, small, medium, and large effects.

Results

Training Load

No significant interaction effects were observed for 25-RM (Pint = 0.326, ηp2=.11) and for total weekly workload of the knee extensions (Pint  = .241, ηp2=.13). At baseline, 25-RM was 21.6 ± 3.9 kg in W and 20.3 ± 5.2 kg in WCP. At the end of the training intervention, 25-RM was increased by 10% in W (23.7 ± 5.6 kg) and by 22% in WCP (24.8 ± 5.6 kg, Ptime < .001). From Week 1 to Week 3, the total weekly workload (Weight lifted × Repetitions × Sets) for the knee extensions increased by 32% in W (from 1,813 ± 335 kg to 2,398 ± 496 kg) versus 50% in WCP (from 1,704 ± 435 kg to 2,552 ± 554 kg, Ptime < .001). Interaction effects were absent for the one-leg squats and drop jumps, as both groups completed the exercise according to the protocol (see Table 3).

Muscular Functional Capacity Tests

Interaction effects were found neither for CMJ (Pint = .899, ηp2=.01), nor for MVCiso (Pint = .649, ηp2=.04) or MVCdyn (Pint = .223, ηp2=.14) in the trained leg (Figure 2). At PRE in the trained leg, CMJ height was 33.9 ± 6.7 cm in W versus 36.1 ± 5.8 cm in WCP. Jump height was not significantly altered by TR1 (Ptime = .388; Figure 2a,b), but compared with PRE, CMJ performance at POST on average was improved by ∼7%–8% in either group (Ptime = .003). MVCiso at PRE in the trained leg was 241 ± 34 N·m in W versus 227 ± 46 N·m in WCP (Figure 2c,d). TR1 transiently impaired MVCiso by ∼10% in both groups (Ptime < .001). However, values returned to baseline by POST irrespective of the experimental condition. MVCdyn at PRE in the trained leg was 76 ± 7 N·m in W and 75 ± 12 N·m in WCP, decreasing by ∼8% in both groups after TR1 (Ptime < .001; Figure 2e,f). Compared to PRE, the training intervention increased MVCdyn by ∼10% in both groups (Ptime = .003). In the untrained leg, MVCiso was 229 ± 24 N·m in W versus 208 ± 46 N·m in WCP and was significantly changed neither by the training intervention nor by the experimental conditions (Ptime = .085, Pint = 0.311, ηp2=.11). Conversely, compared with PRE (W: 76 ± 5 N·m, WCP: 69 ± 11 N·m), MVCdyn POST was slightly increased in both groups (W: 81 ± 10 N·m, WCP: 76 ± 10 N·m, Ptime = .011, Pint = 0.637, ηp2=.04).

Figure 2
Figure 2

—Effect of W and WCP supplementation on CMJ, MVCiso, and MVCdyn performance during overload training. Note. CMJ (a and b) performance, MVCiso (c and d), and MVCdyn (e and f) knee extension torques were measured before (PRE), 48 hours after the first training session (TR1+48hr), and at the end of the 3-week resistance training program (POST) aiming to specifically overload the knee extensor muscles by eccentric contractions. During the intervention period, the subjects received  either whey supplements (W, n = 11) or whey protein + collagen peptide supplements (WCP, n = 11) according to a double-blind and randomized study design. Data are mean ± SD (a, c, e) and changes compared to baseline (b, d, f) including the individual data points. #p < .05, both conditions versus PRE. CMJ = counter movement jump; MVCiso = maximal voluntary isometric contraction; MVCdyn = maximal voluntary dynamic contraction.

Citation: International Journal of Sport Nutrition and Exercise Metabolism 34, 2; 10.1123/ijsnem.2023-0070

Blood Analyses

Interaction effects were detected neither for total creatine kinase (Pint = .340, ηp2=.10), nor for P1NP (Pint = .582, ηp2=.05) or IL-6 (Pint = .377, ηp2=.08; Figure 3). TR1 increased serum total creatine kinase about twofold (TR1+48hr) in both groups (Ptime = .002), but values returned to baseline by POST (Figure 3a). Compared to W, serum P1NP concentration at PRE was slightly higher (∼10 ng/ml) in WCP (p = .101; Figure 3b). TR1 did not impact P1NP levels. However, compared with PRE, P1NP levels at POST on average were ∼10% higher in both experimental groups (Ptime = .002). Serum IL-6 levels were constant at ∼0.33 ± 0.24 pg/ml throughout the intervention period irrespective of the experimental group (Figure 3c).

Figure 3
Figure 3

—Effect of W and WCP on blood concentrations of total creatine kinase, P1NP and IL-6. Note. Data are presented as mean ± SD for total creatine kinase, P1NP, and IL-6. Subjects participated in a 3-week resistance training program aiming to specifically overload the knee extensor muscles by eccentric contractions. During the intervention period, the subjects received either whey supplements (W, n = 11) or whey protein + collagen peptide supplements (WCP, n = 11) according to a double-blind and randomized study design. #p < .05, both conditions versus pretest. PRE = pretest; TR1+48hr = 48 hr after TR1; POST = posttest; P1NP = procollagen type 1N-terminal peptide; IL-6 = interleukin 6.

Citation: International Journal of Sport Nutrition and Exercise Metabolism 34, 2; 10.1123/ijsnem.2023-0070

Muscular Pain Perception

No interaction effect was found for pain perception in the exercised leg following the drop jumps (Pint = .141, ηp2=.18). At TR1, pain perception was 1.3 ± 1.1 in both groups and increased equally in both groups to 3.3 ± 2.0 after TR2 (Ptime = .022 vs. TR1). At TR17, pain perception remained slightly elevated compared to TR1 with a score of 2.2 ± 1.7 in both groups (Ptime < .001 vs. TR1).

Food Intake

For energy intake, macronutrient and micronutrient composition were similar between the groups at baseline, and no significant interaction effects were observed. In the total group of subjects, daily energy intake was 10,404 ± 2,614 kJ (Pint = .609, ηp2=.03), with similar fractional intakes of carbohydrates (4,589 ± 1,329 kJ, Pint = .782, ηp2=.01), proteins (2,165 ± 382 kJ, Pint = .325, ηp2=.10), and fat (3,095 ± 1,066 kJ, Pint = .166, ηp2=.18). With the protein supplements included, daily protein intake was 1.76 g·kg−1·day−1 (range: 1.27–2.47 g·kg−1·day−1). Daily vitamin C intake at baseline was 82 ± 49 mg in W and 85 ± 47 mg in WCP and remained constant throughout the study in both groups (Pint = .138, ηp2=.21).

Discussion

The current study aimed to investigate the effects of collagen peptide supplementation during a 3-week eccentric training intervention aiming to cause muscle damage in young fit volunteers. Because postexercise whey protein intake has become a more or less standard nutritional intervention to stimulate muscle repair and training adaptation following resistance training, we chose to compare the effects of whey protein intake alone with the effects of whey protein plus collagen peptide intake within a similar total daily protein intake rate. Earlier studies (Balshaw et al., 2022; Clifford et al., 2019; Jendricke et al., 2020; Kirmse et al., 2019; Lis et al., 2022) have compared the effects of collagen peptide with the effects of a nonprotein placebo, which impairs the ecological validity of the findings in the context of “real-life” athletic training. The initial training session acutely caused muscle damage as well as transiently impaired functional capacity of the knee extensor muscles. Furthermore, the training intervention increased CMJ performance as well as knee-extension strength. However, partly substituting whey protein for collagen peptides at a similar total protein intake rate did not enhance training outcomes compared to whey protein intake alone.

A primary aim of this study was to evaluate the potential of combined collagen peptides and whey protein intake to reduce muscle damage induced by eccentric exercise. Previous research has demonstrated that postexercise whey protein or branched chain amino acids intake can attenuate delayed onset muscle soreness (Jackman et al., 2010; Shimomura et al., 2006) as well as the decline in muscular performance following eccentric muscle contractions (Buckley et al., 2010; Cooke et al., 2010; Hoffman et al., 2010; Pavis et al., 2021). However, these effects did not appear to be explained by elevated rate of postexercise myofibrillar protein synthesis (Pavis et al., 2021). However, this does not exclude the possibility that faster postexercise tendon and muscle connective tissue repair due to elevated rate of muscle collagen synthesis still could contribute to recovery from eccentric muscle damage. Indeed, several studies also found positive effects of collagen peptide supplementation per se on muscle damage symptoms (Lopez et al., 2015) and recovery of muscle strength and power following an acute eccentric exercise bout (Clifford et al., 2019; Prowting et al., 2020). Based on these studies, we hypothesized that the combined intake of whey protein and collagen peptide, thereby potentially targeting different components of the musculoskeletal system, could facilitate recovery during a period of eccentric muscle training. However, 48 hr after the initial eccentric exercise bout, MVCiso and MVCdyn of the knee extensor muscles were reduced to the same degree in both groups. Also, the degree of muscle damage, as indicated by circulating total creatine kinase increase and explicit muscle soreness 48 hr postexercise, was unaffected by substituting whey protein for collagen peptides. This indicates that mixing whey protein with collagen peptides did not beneficially impact recovery from eccentric exercise-induced muscle damage. In keeping with this result, Rindom et al. (2016) previously found recovery of muscular functional capacity and pain during a short period of resistance training overload to be similar between collagen peptides and whey protein only. Taken together, these results suggest that collagen peptide intake does not add to the effects of whey protein to facilitate acute recovery from eccentric exercise. However, this does not exclude the possibility that either supplement alone may still have a beneficial effect, or that the combined intake of whey protein and collagen peptides might be beneficial in different exercise contexts.

Another aim of the study was to evaluate whether substituting whey protein for collagen peptides could benefit functional adaptation to the 3-week training intervention. However, 25-RM for the knee-extension exercise during the training period similarly increased in both experimental groups. In addition, CMJ performance as well as knee extension force (MVCiso and MVCdyn; see Figure 2) in W and WCP similarly increased from PRE to POST. Again, this indicates that collagen peptides intake did not add to the effects of whey protein to potentially enhance recovery from strenuous resistance exercise involving muscle damage. Nonetheless, in one other study (Jacinto et al., 2022), whey protein and collagen peptide yielded similar effects on muscular functional capacity during a 10-week high-resistance training program. This suggests that either supplement may have stimulated postexercise myofibrillar protein synthesis to the same degree. In this regard, Moore et al. (2009) demonstrated that the rate of myofibrillar protein synthesis is maximal at a bolus ingestion of ∼8–9 g of essential amino acids, which corresponds to ∼35 g of pure whey protein, or ∼100 g of pure collagen peptides. This dose of essential amino acids was delivered in both W (∼10.5 g) and WCP (∼8.1 g). Hence, the degree of myofibrillar protein synthesis stimulation probably was similar between the two experimental conditions. Along the same line, muscle collagen synthesis most likely was not different between the conditions as Oikawa et al. (2020) observed similar rates of muscle collagen synthesis in older women following collagen peptides or whey protein ingestion. In addition, Aussieker et al. (2022) recently demonstrated that neither whey protein nor collagen peptides stimulated muscle connective tissue protein synthesis during the early stages of recovery following a resistance exercise session in young recreational athletes. These findings are in contrast with a seminal study by Shaw et al. (2017) showing that serum obtained from healthy volunteers who ingested gelatin 1 hr prior to exercise, enhanced the rate of collagen synthesis in an engineered ligament preparation in vitro. However, such an effect may not occur upon a prevalent oral dose of collagen peptides in vivo.

To investigate whether collagen peptide supplementation could increase connective tissue repair in the conditions of the current study, we also measured circulating P1NP levels, a biomarker of whole-body collagen synthesis. The training intervention slightly increased plasma P1NP concentration, but this effect was independent of the experimental conditions. This finding is consistent with other studies reporting collagen peptide supplementation not altering plasma P1NP concentration following exercise in healthy males (Clifford et al., 2019; Lis & Baar, 2019). However, total collagen mass and the rate of collagen turnover are substantially higher in bone than in soft tissues (Koivula et al., 2012). Hence, circulating P1NP primarily reflects alterations in bone collagen turnover. Thus, training along with whey protein or whey protein + collagen peptide intake in the conditions of the current study probably similarly upregulated bone collagen turnover. Nonetheless, König et al. (2018) found a favorable shift in markers of bone remodeling after 12 months of 5 g daily collagen peptide supplementation in postmenopausal women. This suggests that longer interventions, or interventions in individuals with reduced bone mass, may be necessary for collagen peptide supplementation to potentially benefit bone tissue remodeling.

In contrast to earlier studies (Clifford et al., 2019; Lis et al., 2022; Shaw et al., 2017), we did not use vitamin C as an adjuvant supplement in the current protocol. Vitamin C is an important cofactor in the regulation of collagen synthesis and cross-linking (Pinnell, 1985). Hence, vitamin C deficiency conceivably could downregulate collagen synthesis. However, whether vitamin C supplementation in the absence of vitamin C deficiency in healthy individuals may enhance collagen synthesis is at present unknown. In fact, none of the studies that used vitamin C in combination with collagen peptides (Clifford et al., 2019; Lis et al., 2022) included a control group without vitamin C intake, which excludes elucidating the role of vitamin C. In addition, vitamin C is a strong anti-oxidant, which might negatively impact training adaptation (Merry & Ristow, 2016). Therefore, we chose not to use vitamin C as co-therapy in the context of the current study. The recommended dietary allowance for vitamin C in male adults is 90 mg (Institute of Medicine, 2000). In either experimental group half of the subjects had daily vitamin C intake slightly below the recommended dietary allowance, while the other half were above. Therefore, we cannot exclude that vitamin C deficiency may have limited whole-body collagen synthesis in some subjects. Future studies need to address whether supplemental vitamin C intake may play a role in regulating postexercise collagen synthesis in young fit individuals.

In conclusion, the present study shows that for a similar supplementary protein intake (∼45 g·day−1), partly substituting whey protein for collagen peptides neither improved indices of muscle damage or acute recovery of muscular performance, nor improved muscular strength and power during a 3-week training program involving high load of eccentric muscle contractions.

Acknowledgments

The authors thank all the subjects for their participation in the study. All experiments were performed at the Exercise Physiology Research Group at KU Leuven, Belgium. The study was funded by Rousselot BV. Rousselot BV packed and provided the supplements but was involved neither in the organization and execution of the experiments, nor in data analyses and interpretation. But Rousselot BV was allowed to comment on the manuscript before submission. Poffé is supported by a Research Foundation - Flanders Postdoctoral Research Grant (1244921N). The study was retrospectively registered in a clinical trial database (ClinicalTrials.gov—NCT05425407). All raw data that support the findings of this study are available from the corresponding author upon reasonable request. Conception and design of the study: Robberechts, Poffé, Bogaerts, and Hespel. Data collection and data analyses: Robberechts, Poffé, and Ampe. Interpretation of the data: Robberechts and Hespel. Manuscript drafting: Robberechts, Poffé, Ampe, and Hespel. Critically evaluated the manuscript and approved it for submission: All authors. Agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved: All authors. All persons designated as authors qualify for authorship, and all those who qualify for authorship are listed.

References

  • Aussieker, T., Hilkens, L., Holwerda, A., Fuchs, C., Houben, L.H.P., Senden, J., Snijders, J.D., & van Loon, L.J. (2022). Collagen and whey protein ingestion do not increase muscle connective tissue protein synthesis rates during recovery from exercise in male and female recreational athletes. Medicine & Science in Sports & Exercise, 55(10), 17921802.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Baar, K. (2017). Minimizing injury and maximizing return to play: Lessons from engineered ligaments. Sports Medicine, 47(1), 511.

  • Balshaw, T.G., Funnell, M.P., McDermott, E., Maden-Wilkinson, T.M., Abela, S., Quteishat, B., Edsey, M., James, L.J., & Folland, J.P. (2022). The effect of specific bioactive collagen peptides on function and muscle remodeling during human resistance training. Acta Physiologica, 237(2), Article e13903.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Buckley, J.D., Thomson, R.L., Coates, A.M., Howe, P.R.C., DeNichilo, M.O., & Rowney, M.K. (2010). Supplementation with a whey protein hydrolysate enhances recovery of muscle force-generating capacity following eccentric exercise. Journal of Science and Medicine in Sport, 13(1), 178181.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Clifford, T., Ventress, M., Allerton, D.M., Stansfield, S., Tang, J.C.Y., Fraser, W.D., Vanhoecke, B., Prawitt, J., & Stevenson, E. (2019). The effects of collagen peptides on muscle damage, inflammation and bone turnover following exercise: A randomized, controlled trial. Amino Acids, 51(4), 691704.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Cooke, M.B., Rybalka, E., Stathis, C.G., Cribb, P.J., & Hayes, A. (2010). Whey protein isolate attenuates strength decline after eccentrically-induced muscle damage in healthy individuals. Journal of the International Society of Sports Nutrition, 7(1), 19.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • de Paz-Lugo, P., Lupiáñez, J.A., & Meléndez-Hevia, E. (2018). High glycine concentration increases collagen synthesis by articular chondrocytes in vitro: Acute glycine deficiency could be an important cause of osteoarthritis. Amino Acids, 50(10), 13571365.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Devries, M.C., & Phillips, S.M. (2015). Supplemental protein in support of muscle mass and health: Advantage whey. Journal of Food Science, 80, A8A15.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Farup, J., Rahbek, S.K., Vendelbo, M.H., Matzon, A., Hindhede, J., Bejder, A., Ringgard, S., & Vissing, K. (2014). Whey protein hydrolysate augments tendon and muscle hypertrophy independent of resistance exercise contraction mode. Scandinavian Journal of Medicine & Science in Sports, 24(5), 788798.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hespel, P., Eijnde, B.O., Leemputte, M, Ursø, B., Greenhaff, P.L., Labarque, V., Dymarkowski, S., Hecke, P., & Richter, E.A. (2001). Oral creatine supplementation facilitates the rehabilitation of disuse atrophy and alters the expression of muscle myogenic factors in humans. The Journal of Physiology, 536(2), 625633.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hoffman, J.R., Ratamess, N.A., Tranchina, C.P., Rashti, S.L., Kang, J., & Faigenbaum, A.D. (2010). Effect of a proprietary protein supplement on recovery indices following resistance exercise in strength/power athletes. Amino Acids, 38(3), 771778.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Holm, L., Rahbek, S.K., Farup, J., Vendelbo, M.H., & Vissing, K. (2017). Contraction mode and whey protein intake affect the synthesis rate of intramuscular connective tissue. Muscle and Nerve, 55(1), 128130.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Holwerda, A.M., Trommelen, J., Kouw, I.W.K., Senden, J.M., Goessens, J.P.B., Van Kranenburg, J., Gijsen, A.P., Verdijk, L.B., & Van Loon, L.J.C. (2021). Exercise plus presleep protein ingestion increases overnight muscle connective tissue protein synthesis rates in healthy older men. International Journal of Sport Nutrition and Exercise Metabolism, 31(3), 217226.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Institute of Medicine (US) Panel on Dietary Antioxidants and Related Compounds. (2000). Dietary reference intakes for vitamin C, vitamin E, selenium, and carotenoids. National Academies Press.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jacinto, J.L., Nunes, J.P., Gorissen, S.H.M., Capel, D.M.G., Bernardes, A.G., Ribeiro, A.S., Cyrino, E.S., Phillips, S.M., & Aguiar, A.F. (2022). Whey protein supplementation is superior to leucine-matched collagen peptides to increase muscle thickness during a 10-week resistance training program in untrained young adults. International Journal of Sport Nutrition and Exercise Metabolism, 32(3), 133143.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jackman, S.R., Witard, O.C., Jeukendrup, A.E., Tipton, K.D., Jackman, A., Witard, O.C., Jeukendrup, A.E., & Tipton, K.D. (2010). Branched-chain amino acid ingestion can ameliorate soreness from eccentric exercise. Medicine & Science in Sports & Exercise, 42(5), 962970.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jendricke, P., Centner, C., Zdzieblik, D., Gollhofer, A., & König, D. (2019). Specific collagen peptides in combination with resistance training improve body composition and regional muscle strength in premenopausal women: A randomized controlled trial. Nutrients, 11(4), Article 892.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jendricke, P., Kohl, J., Centner, C., Gollhofer, A., & König, D. (2020). Influence of specific collagen peptides and concurrent training on cardiometabolic parameters and performance indices in women: A randomized controlled trial. Frontiers in Nutrition, 7, Article 580918.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kirmse, M., Oertzen-Hagemann, V., de Marées, M., Bloch, W., Platen, P., DeMarées, M., Platen, P., & Bloch, W. (2019). Prolonged collagen peptide supplementation and resistance exercise training affects body composition in recreationally active men. Nutrients, 11(5), Article 1154.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kjær, M. (2004). Role of extracellular matrix in adaptation of tendon and skeletal muscle to mechanical loading. Physiological Reviews, 84(2), 649698.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Koivula, M.K., Risteli, L., & Risteli, J. (2012). Measurement of aminoterminal propeptide of type I procollagen (PINP) in serum. Clinical Biochemistry, 45(12), 920927.

    • Search Google Scholar
    • Export Citation
  • König, D., Oesser, S., Scharla, S., Zdzieblik, D., & Gollhofer, A. (2018). Specific collagen peptides improve bone mineral density and bone markers in postmenopausal women—A randomized controlled study. Nutrients, 10(1), Article 97.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Koopman, R., Saris, W.H.M., Wagenmakers, A.J.M., & Van Loon, L.J.C. (2007). Nutritional interventions to promote post-exercise muscle protein synthesis. Sports Medicine, 37(10), 895906.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lis, D.M., & Baar, K. (2019). Effects of different vitamin c–enriched collagen derivatives on collagen synthesis. International Journal of Sport Nutrition and Exercise Metabolism, 29(5), 526531.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lis, D.M., Jordan, M., Lipuma, T., Smith, T., Schaal, K., & Baar, K. (2022). Collagen and vitamin c supplementation increases lower limb rate of force development. International Journal of Sport Nutrition and Exercise Metabolism, 32(2), 6573.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lopez, H.L., Ziegenfuss, T.N., & Park, J. (2015). Evaluation of the effects of biocell collagen, a novel cartilage extract, on connective tissue support and functional recovery from exercise. Integrative Medicine: A Clinician’s Journal, 14(3), 3038.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Meléndez-Hevia, E., De Paz-Lugo, P., Cornish-Bowden, A., & Cárdenas, M.L. (2009). A weak link in metabolism: The metabolic capacity for glycine biosynthesis does not satisfy the need for collagen synthesis. Journal of Biosciences, 34(6), 853872.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Merry, T.L., & Ristow, M. (2016). Do antioxidant supplements interfere with skeletal muscle adaptation to exercise training? The Journal of Physiology, 594(18), Article 5135.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Moore, D.R., Robinson, M.J., Fry, J.L., Tang, J.E., Glover, E.I., Wilkinson, S.B., Prior, T., Tarnopolsky, M.A., & Phillips, S.M. (2009). Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. The American Journal of Clinical Nutrition, 89(1), 161168.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Oikawa, S.Y., Kamal, M.J., Webb, E.K., McGlory, C., Baker, S.K., & Phillips, S.M. (2020). Whey protein but not collagen peptides stimulate acute and longer-term muscle protein synthesis with and without resistance exercise in healthy older women: A randomized controlled trial. The American Journal of Clinical Nutrition, 111(3), 708718.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Oikawa, S.Y., Macinnis, M.J., Tripp, T.R., McGlory, C., Baker, S.K., & Phillips, S.M. (2020). Lactalbumin, not collagen, augments muscle protein synthesis with aerobic exercise. Medicine & Science in Sports & Exercise, 52(6), 13941403.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Oikawa, S.Y., McGlory, C., D’Souza, L.K., Morgan, A.K., Saddler, N.I., Baker, S.K., Parise, G., & Phillips, S.M. (2018). A randomized controlled trial of the impact of protein supplementation on leg lean mass and integrated muscle protein synthesis during inactivity and energy restriction in older persons. American Journal of Clinical Nutrition, 108(5), 10601068.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pavis, G.F., Jameson, T.S.O., Dirks, M.L., Lee, B.P., Abdelrahman, D.R., Murton, A.J., Porter, C., Alamdari, N., Mikus, C.R., Wall, B.T., & Stephens, F.B. (2021). Improved recovery from skeletal muscle damage is largely unexplained by myofibrillar protein synthesis or inflammatory and regenerative gene expression pathways. American Journal of Physiology Endocrinology and Metabolism, 320(2), E291E305.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Phillips, S.M., Tang, J.E., & Moore, D.R. (2009). The role of milk- and soy-based protein in support of muscle protein synthesis and muscle protein accretion in young and elderly persons. Journal of the American College of Nutrition, 28(4), 343354.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Phillips, S.M., & van Loon, L.J.C. (2011). Dietary protein for athletes: From requirements to optimum adaptation. Journal of Sports Sciences, 29(Suppl. 1), S29S38.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pinnell, S.R. (1985). Regulation of collagen biosynthesis by ascorbic acid: A review. The Yale Journal of Biology and Medicine, 58, 553559.

    • Search Google Scholar
    • Export Citation
  • Prowting, J.L., Bemben, D., Black, C.D., Day, E.A., & Campbell, J.A. (2020). Effects of collagen peptides on recovery following eccentric exercise in resistance-trained males—A pilot study. International Journal of Sport Nutrition and Exercise Metabolism, 31(1), 3239.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Rindom, E., Nielsen, M.H., Kececi, K., Jensen, M.E., Vissing, K., & Farup, J. (2016). Effect of protein quality on recovery after intense resistance training. European Journal of Applied Physiology, 116(11–12), 22252236.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Shaw, G., Lee-Barthel, A., Ross, M.L., Wang, B., & Baar, K. (2017). Vitamin C–enriched gelatin supplementation before intermittent activity augments collagen synthesis. The American Journal of Clinical Nutrition, 105(1), 136143.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Shimomura, Y., Yamamoto, Y., Bajotto, G., Sato, J., Murakami, T., Shimomura, N., Kobayashi, H., & Mawatari, K. (2006). Nutraceutical effects of branched-chain amino acids on skeletal muscle. The Journal of Nutrition, 136(2), 529S532S.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yamada, S., Nagaoka, H., Terajima, M., Tsuda, N., Hayashi, Y., & Yamauchi, M. (2013). Effects of fish collagen peptides on collagen post-translational modifications and mineralization in an osteoblastic cell culture system. Dental Materials Journal, 32(1), 8895.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zdzieblik, D., Brame, J., Oesser, S., Gollhofer, A., & König, D. (2021). The influence of specific bioactive collagen peptides on knee joint discomfort in young physically active adults: A randomized controlled trial. Nutrients, 13(2), 113.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zdzieblik, D., Oesser, S., Baumstark, M.W., Gollhofer, A., & König, D. (2015). Collagen peptide supplementation in combination with resistance training improves body composition and increases muscle strength in elderly sarcopenic men: A randomised controlled trial. British Journal of Nutrition, 114(8), 12371245.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Collapse
  • Expand
  • Figure 1

    —Overview of the study design. Note. The subjects participated in a 3-week resistance training program aiming to specifically overload the knee extensor muscles by eccentric contractions. During the intervention period, the subjects received either whey supplements (W, n = 11) or whey protein + collagen peptide supplements (WCP, n = 11) according to a double-blind and randomized study design. D = day; TR = training session; TR1+48h, 48 hr after training session 1.

  • Figure 2

    —Effect of W and WCP supplementation on CMJ, MVCiso, and MVCdyn performance during overload training. Note. CMJ (a and b) performance, MVCiso (c and d), and MVCdyn (e and f) knee extension torques were measured before (PRE), 48 hours after the first training session (TR1+48hr), and at the end of the 3-week resistance training program (POST) aiming to specifically overload the knee extensor muscles by eccentric contractions. During the intervention period, the subjects received  either whey supplements (W, n = 11) or whey protein + collagen peptide supplements (WCP, n = 11) according to a double-blind and randomized study design. Data are mean ± SD (a, c, e) and changes compared to baseline (b, d, f) including the individual data points. #p < .05, both conditions versus PRE. CMJ = counter movement jump; MVCiso = maximal voluntary isometric contraction; MVCdyn = maximal voluntary dynamic contraction.

  • Figure 3

    —Effect of W and WCP on blood concentrations of total creatine kinase, P1NP and IL-6. Note. Data are presented as mean ± SD for total creatine kinase, P1NP, and IL-6. Subjects participated in a 3-week resistance training program aiming to specifically overload the knee extensor muscles by eccentric contractions. During the intervention period, the subjects received either whey supplements (W, n = 11) or whey protein + collagen peptide supplements (WCP, n = 11) according to a double-blind and randomized study design. #p < .05, both conditions versus pretest. PRE = pretest; TR1+48hr = 48 hr after TR1; POST = posttest; P1NP = procollagen type 1N-terminal peptide; IL-6 = interleukin 6.

  • Aussieker, T., Hilkens, L., Holwerda, A., Fuchs, C., Houben, L.H.P., Senden, J., Snijders, J.D., & van Loon, L.J. (2022). Collagen and whey protein ingestion do not increase muscle connective tissue protein synthesis rates during recovery from exercise in male and female recreational athletes. Medicine & Science in Sports & Exercise, 55(10), 17921802.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Baar, K. (2017). Minimizing injury and maximizing return to play: Lessons from engineered ligaments. Sports Medicine, 47(1), 511.

  • Balshaw, T.G., Funnell, M.P., McDermott, E., Maden-Wilkinson, T.M., Abela, S., Quteishat, B., Edsey, M., James, L.J., & Folland, J.P. (2022). The effect of specific bioactive collagen peptides on function and muscle remodeling during human resistance training. Acta Physiologica, 237(2), Article e13903.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Buckley, J.D., Thomson, R.L., Coates, A.M., Howe, P.R.C., DeNichilo, M.O., & Rowney, M.K. (2010). Supplementation with a whey protein hydrolysate enhances recovery of muscle force-generating capacity following eccentric exercise. Journal of Science and Medicine in Sport, 13(1), 178181.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Clifford, T., Ventress, M., Allerton, D.M., Stansfield, S., Tang, J.C.Y., Fraser, W.D., Vanhoecke, B., Prawitt, J., & Stevenson, E. (2019). The effects of collagen peptides on muscle damage, inflammation and bone turnover following exercise: A randomized, controlled trial. Amino Acids, 51(4), 691704.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Cooke, M.B., Rybalka, E., Stathis, C.G., Cribb, P.J., & Hayes, A. (2010). Whey protein isolate attenuates strength decline after eccentrically-induced muscle damage in healthy individuals. Journal of the International Society of Sports Nutrition, 7(1), 19.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • de Paz-Lugo, P., Lupiáñez, J.A., & Meléndez-Hevia, E. (2018). High glycine concentration increases collagen synthesis by articular chondrocytes in vitro: Acute glycine deficiency could be an important cause of osteoarthritis. Amino Acids, 50(10), 13571365.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Devries, M.C., & Phillips, S.M. (2015). Supplemental protein in support of muscle mass and health: Advantage whey. Journal of Food Science, 80, A8A15.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Farup, J., Rahbek, S.K., Vendelbo, M.H., Matzon, A., Hindhede, J., Bejder, A., Ringgard, S., & Vissing, K. (2014). Whey protein hydrolysate augments tendon and muscle hypertrophy independent of resistance exercise contraction mode. Scandinavian Journal of Medicine & Science in Sports, 24(5), 788798.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hespel, P., Eijnde, B.O., Leemputte, M, Ursø, B., Greenhaff, P.L., Labarque, V., Dymarkowski, S., Hecke, P., & Richter, E.A. (2001). Oral creatine supplementation facilitates the rehabilitation of disuse atrophy and alters the expression of muscle myogenic factors in humans. The Journal of Physiology, 536(2), 625633.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hoffman, J.R., Ratamess, N.A., Tranchina, C.P., Rashti, S.L., Kang, J., & Faigenbaum, A.D. (2010). Effect of a proprietary protein supplement on recovery indices following resistance exercise in strength/power athletes. Amino Acids, 38(3), 771778.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Holm, L., Rahbek, S.K., Farup, J., Vendelbo, M.H., & Vissing, K. (2017). Contraction mode and whey protein intake affect the synthesis rate of intramuscular connective tissue. Muscle and Nerve, 55(1), 128130.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Holwerda, A.M., Trommelen, J., Kouw, I.W.K., Senden, J.M., Goessens, J.P.B., Van Kranenburg, J., Gijsen, A.P., Verdijk, L.B., & Van Loon, L.J.C. (2021). Exercise plus presleep protein ingestion increases overnight muscle connective tissue protein synthesis rates in healthy older men. International Journal of Sport Nutrition and Exercise Metabolism, 31(3), 217226.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Institute of Medicine (US) Panel on Dietary Antioxidants and Related Compounds. (2000). Dietary reference intakes for vitamin C, vitamin E, selenium, and carotenoids. National Academies Press.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jacinto, J.L., Nunes, J.P., Gorissen, S.H.M., Capel, D.M.G., Bernardes, A.G., Ribeiro, A.S., Cyrino, E.S., Phillips, S.M., & Aguiar, A.F. (2022). Whey protein supplementation is superior to leucine-matched collagen peptides to increase muscle thickness during a 10-week resistance training program in untrained young adults. International Journal of Sport Nutrition and Exercise Metabolism, 32(3), 133143.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jackman, S.R., Witard, O.C., Jeukendrup, A.E., Tipton, K.D., Jackman, A., Witard, O.C., Jeukendrup, A.E., & Tipton, K.D. (2010). Branched-chain amino acid ingestion can ameliorate soreness from eccentric exercise. Medicine & Science in Sports & Exercise, 42(5), 962970.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jendricke, P., Centner, C., Zdzieblik, D., Gollhofer, A., & König, D. (2019). Specific collagen peptides in combination with resistance training improve body composition and regional muscle strength in premenopausal women: A randomized controlled trial. Nutrients, 11(4), Article 892.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jendricke, P., Kohl, J., Centner, C., Gollhofer, A., & König, D. (2020). Influence of specific collagen peptides and concurrent training on cardiometabolic parameters and performance indices in women: A randomized controlled trial. Frontiers in Nutrition, 7, Article 580918.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kirmse, M., Oertzen-Hagemann, V., de Marées, M., Bloch, W., Platen, P., DeMarées, M., Platen, P., & Bloch, W. (2019). Prolonged collagen peptide supplementation and resistance exercise training affects body composition in recreationally active men. Nutrients, 11(5), Article 1154.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kjær, M. (2004). Role of extracellular matrix in adaptation of tendon and skeletal muscle to mechanical loading. Physiological Reviews, 84(2), 649698.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Koivula, M.K., Risteli, L., & Risteli, J. (2012). Measurement of aminoterminal propeptide of type I procollagen (PINP) in serum. Clinical Biochemistry, 45(12), 920927.

    • Search Google Scholar
    • Export Citation
  • König, D., Oesser, S., Scharla, S., Zdzieblik, D., & Gollhofer, A. (2018). Specific collagen peptides improve bone mineral density and bone markers in postmenopausal women—A randomized controlled study. Nutrients, 10(1), Article 97.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Koopman, R., Saris, W.H.M., Wagenmakers, A.J.M., & Van Loon, L.J.C. (2007). Nutritional interventions to promote post-exercise muscle protein synthesis. Sports Medicine, 37(10), 895906.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lis, D.M., & Baar, K. (2019). Effects of different vitamin c–enriched collagen derivatives on collagen synthesis. International Journal of Sport Nutrition and Exercise Metabolism, 29(5), 526531.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lis, D.M., Jordan, M., Lipuma, T., Smith, T., Schaal, K., & Baar, K. (2022). Collagen and vitamin c supplementation increases lower limb rate of force development. International Journal of Sport Nutrition and Exercise Metabolism, 32(2), 6573.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lopez, H.L., Ziegenfuss, T.N., & Park, J. (2015). Evaluation of the effects of biocell collagen, a novel cartilage extract, on connective tissue support and functional recovery from exercise. Integrative Medicine: A Clinician’s Journal, 14(3), 3038.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Meléndez-Hevia, E., De Paz-Lugo, P., Cornish-Bowden, A., & Cárdenas, M.L. (2009). A weak link in metabolism: The metabolic capacity for glycine biosynthesis does not satisfy the need for collagen synthesis. Journal of Biosciences, 34(6), 853872.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Merry, T.L., & Ristow, M. (2016). Do antioxidant supplements interfere with skeletal muscle adaptation to exercise training? The Journal of Physiology, 594(18), Article 5135.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Moore, D.R., Robinson, M.J., Fry, J.L., Tang, J.E., Glover, E.I., Wilkinson, S.B., Prior, T., Tarnopolsky, M.A., & Phillips, S.M. (2009). Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. The American Journal of Clinical Nutrition, 89(1), 161168.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Oikawa, S.Y., Kamal, M.J., Webb, E.K., McGlory, C., Baker, S.K., & Phillips, S.M. (2020). Whey protein but not collagen peptides stimulate acute and longer-term muscle protein synthesis with and without resistance exercise in healthy older women: A randomized controlled trial. The American Journal of Clinical Nutrition, 111(3), 708718.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Oikawa, S.Y., Macinnis, M.J., Tripp, T.R., McGlory, C., Baker, S.K., & Phillips, S.M. (2020). Lactalbumin, not collagen, augments muscle protein synthesis with aerobic exercise. Medicine & Science in Sports & Exercise, 52(6), 13941403.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Oikawa, S.Y., McGlory, C., D’Souza, L.K., Morgan, A.K., Saddler, N.I., Baker, S.K., Parise, G., & Phillips, S.M. (2018). A randomized controlled trial of the impact of protein supplementation on leg lean mass and integrated muscle protein synthesis during inactivity and energy restriction in older persons. American Journal of Clinical Nutrition, 108(5), 10601068.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pavis, G.F., Jameson, T.S.O., Dirks, M.L., Lee, B.P., Abdelrahman, D.R., Murton, A.J., Porter, C., Alamdari, N., Mikus, C.R., Wall, B.T., & Stephens, F.B. (2021). Improved recovery from skeletal muscle damage is largely unexplained by myofibrillar protein synthesis or inflammatory and regenerative gene expression pathways. American Journal of Physiology Endocrinology and Metabolism, 320(2), E291E305.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Phillips, S.M., Tang, J.E., & Moore, D.R. (2009). The role of milk- and soy-based protein in support of muscle protein synthesis and muscle protein accretion in young and elderly persons. Journal of the American College of Nutrition, 28(4), 343354.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Phillips, S.M., & van Loon, L.J.C. (2011). Dietary protein for athletes: From requirements to optimum adaptation. Journal of Sports Sciences, 29(Suppl. 1), S29S38.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pinnell, S.R. (1985). Regulation of collagen biosynthesis by ascorbic acid: A review. The Yale Journal of Biology and Medicine, 58, 553559.

    • Search Google Scholar
    • Export Citation
  • Prowting, J.L., Bemben, D., Black, C.D., Day, E.A., & Campbell, J.A. (2020). Effects of collagen peptides on recovery following eccentric exercise in resistance-trained males—A pilot study. International Journal of Sport Nutrition and Exercise Metabolism, 31(1), 3239.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Rindom, E., Nielsen, M.H., Kececi, K., Jensen, M.E., Vissing, K., & Farup, J. (2016). Effect of protein quality on recovery after intense resistance training. European Journal of Applied Physiology, 116(11–12), 22252236.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Shaw, G., Lee-Barthel, A., Ross, M.L., Wang, B., & Baar, K. (2017). Vitamin C–enriched gelatin supplementation before intermittent activity augments collagen synthesis. The American Journal of Clinical Nutrition, 105(1), 136143.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Shimomura, Y., Yamamoto, Y., Bajotto, G., Sato, J., Murakami, T., Shimomura, N., Kobayashi, H., & Mawatari, K. (2006). Nutraceutical effects of branched-chain amino acids on skeletal muscle. The Journal of Nutrition, 136(2), 529S532S.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yamada, S., Nagaoka, H., Terajima, M., Tsuda, N., Hayashi, Y., & Yamauchi, M. (2013). Effects of fish collagen peptides on collagen post-translational modifications and mineralization in an osteoblastic cell culture system. Dental Materials Journal, 32(1), 8895.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zdzieblik, D., Brame, J., Oesser, S., Gollhofer, A., & König, D. (2021). The influence of specific bioactive collagen peptides on knee joint discomfort in young physically active adults: A randomized controlled trial. Nutrients, 13(2), 113.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zdzieblik, D., Oesser, S., Baumstark, M.W., Gollhofer, A., & König, D. (2015). Collagen peptide supplementation in combination with resistance training improves body composition and increases muscle strength in elderly sarcopenic men: A randomised controlled trial. British Journal of Nutrition, 114(8), 12371245.

    • Crossref
    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 969 969 0
Full Text Views 1225 1225 568
PDF Downloads 837 837 251