participants ( Harms-Ringdahl et al., 2012 ). In a small study with nine anaerobic sport athletes and six controls, intake of 200 ml tomato juice for 2 months was linked to lower blood levels of muscle damage biomarkers including creatine kinase (CK) and lactate dehydrogenase ( Tsitsimpikou et al., 2013
David C. Nieman, Courtney L. Capps, Christopher R. Capps, Zack L. Shue and Jennifer E. McBride
Jordan Bettleyon and Thomas W. Kaminski
Question Does LLLT decrease muscle-damaging mediators effecting player fatigue and DOMS after performance in soccer athletes versus sham treatment? Clinical Bottom Line The LLLT either at 10, 30, or 50 J performed at a minimum of 2 locations on the rectus femoris, vastus lateralis, and vastus medialis
Jaci L. VanHeest, Jim Stoppani, Tim P. Scheett, Valerie Collins, Melissa Roti, Jeffrey Anderson, George J. Allen, Jay Hoffman, William J. Kraemer and Carl M. Maresh
To determine the effects of Vicoprofen® and ibuprofen on aerobic performance, agility, and pain after exercise-induced muscle damage.
Double-blind randomized, placebo-controlled, repeated-dose clinical trial.
Human-performance and sports-medicine laboratory.
36 healthy men.
Methods and Measures:
Baseline testing was performed, 72 hours after which subjects performed eccentric exercise to induce muscle damage. They were evaluated for pain 24 hours postdamage and placed randomly into 3 groups: Vicoprofen (VIC), ibuprofen, or placebo (P). Postdamage testing was performed every day for 5 days. Subjects performed an economy run and a t-agility test to determine exercise performance.
The drugs had no significant effect on performance throughout the 5-day evaluation period. Pain was lower at days 4 and 5 in the VIC group than in P.
It appears that Vicoprofen reduced pain after muscle damage, but the drug interventions did not enhance performance in aerobic and agility tasks.
Chariklia K. Deli, Ioannis G. Fatouros, Vassilis Paschalis, Kalliopi Georgakouli, Athanasios Zalavras, Alexandra Avloniti, Yiannis Koutedakis and Athanasios Z. Jamurtas
Research regarding exercise-induced muscle-damage mainly focuses on adults. The present study examined exercise-induced muscle-damage responses in adults compared with children.
Eleven healthy boys (10–12 y) and 15 healthy men (18–45 y) performed 5 sets of 15 maximal eccentric contractions of the knee extensors. Range of motion (ROM), delayed onset muscle soreness (DOMS) during squat and walking, and peak isometric, concentric and eccentric torque were assessed before, post, 24, 48, 72, and 96 hr postexercise. Creatine kinase (CK) activity was assessed before and 72 hr postexercise.
Eccentric exercise resulted in DOMS during squat that persisted for up to 96h in men, and 48 hr in boys (p < .05), and DOMS during walking that persisted for up to 72 hr in men, and 48 hr in boys (p < .01). The ROM was lower in both age groups 48 hr postexercise (p < .001). Isometric (p < .001), concentric (p < .01) and eccentric (p < .01) force decreased post, and up to 48 hr postexercise in men. Except for a reduction in isometric force immediately after exercise, no other changes occurred in boys’ isokinetic force. CK activity increased in men at 72 hr postexercise compared with pre exercise levels (p = .05).
Our data provide further confirmation that children are less susceptible to exercise-induced muscle damage compared with adults.
Mary P. Miles, Sherri D. Pearson, Jan M. Andring, Jessy R. Kidd and Stella L. Volpe
The purpose of this investigation was to determine whether carbohydrate supplementation during the frst 2 d post exercise recovery influenced the inflammation (IL-6, C-reactive protein [CRP], and cortisol) and muscle-damage responses. Eight participants performed a high-force eccentric elbow-fexion exercise to induce muscle soreness and inflammation and then consumed carbohydrate (0.25 g·kg−1·h−1) or an equal volume of placebo during hours 0–12 and 24–36 post exercise in a double-blind, crossover protocol. Muscle soreness; mid brachial arm circumference; blood glucose, IL-6, CRP, cortisol, and creatine-kinase (CK) activity; and maximal force production were measured pre exercise and 4, 8, 12, 24, 48, and 120 h post exercise. Plasma IL-6 increased, F(5) = 5.27, P < 0.05, 8 h post exercise, with no difference between carbohydrate and placebo conditions. Changes in muscle soreness, arm circumference, strength, and serum CK activity were consistent with small amounts of muscle damage and did not differ between conditions. The authors conclude that carbohydrate supplementation during recovery from soreness-inducing exercise does not influence the delayed IL-6 response temporally linked to inflammation or indications of muscle damage. Thus, increased carbohydrate consumption at levels consistent with recommendations for replenishing glycogen stores does not impair or promote the immune and muscle responses.
Kevin S. O’Fallon, Diksha Kaushik, Bozena Michniak-Kohn, C. Patrick Dunne, Edward J. Zambraski and Priscilla M. Clarkson
The flavonoid quercetin is purported to have potent antioxidant and anti-inflammatory properties. This study examined if quercetin supplementation attenuates indicators of exercise-induced muscle damage in a doubleblind laboratory study. Thirty healthy subjects were randomized to quercetin (QU) or placebo (PL) supplementation and performed 2 separate sessions of 24 eccentric contractions of the elbow flexors. Muscle strength, soreness, resting arm angle, upper arm swelling, serum creatine kinase (CK) activity, plasma quercetin (PQ), interleukin-6 (IL-6), and C-reactive protein (CRP) were assessed before and for 5 d after exercise. Subjects then ingested nutrition bars containing 1,000 mg/d QU or PL for 7 d before and 5 d after the second exercise session, using the opposite arm. PQ reached 202 ± 52 ng/ml after 7 d of supplementation and remained elevated during the 5-d postexercise recovery period (p < .05). Subjects experienced strength loss (peak = 47%), muscle soreness (peak = 39 ± 6 mm), reduced arm angle (–7° ± 1°), CK elevations (peak = 3,307 ± 1,481 U/L), and arm swelling (peak = 11 ± 2 mm; p < .0001), indicating muscle damage and inflammation; however, differences between treatments were not detected. Eccentric exercise did not alter plasma IL-6 (peak = 1.9 pg/ml) or CRP (peak = 1.6 mg/L) relative to baseline or by treatment. QU supplementation had no effect on markers of muscle damage or inflammation after eccentric exercise of the elbow flexors.
John G. Seifert, Ronald W. Kipp, Markus Amann and Oladele Gazal
This study examined energy and fluid supplementation on indices of muscle damage during alpine skiing. Skiers were assigned to a carbohydrate-protein (CP), placebo (PL), or no fluid (NF) group. CP and PL ingested 1.62 L during and after skiing. Myoglobin did not change from pre-skiing (PS) to 2 h post-skiing (2PS) for CP (24.8 ± 1.4 and 25.6 ± 1.6 ng/mL), but rose significantly from 26.4 ± 1.3 to 40.0 ± 2.8 ng/mL for PL and from 29.0 ± 1.3 to 82.9 ± 3.6 ng/mL for NF. Creatine kinase was maintained from PRE to 2 PS for CP, but increased significantly from 117 ± 7.2 to 174 ± 43.4 U/L for PL and from 126 ± 23.2 to 243 ± 34.3 U/L for NF. This study demonstrates that ingestion of a CP beverage minimized muscle damage indices during skiing compared to PL and NF and that ingesting fluids may also minimize muscle damage compared to a NF condition.
Che-Hsiu Chen, Trevor C. Chen, Mei-Hwa Jan and Jiu-Jenq Lin
To examine whether an acute bout of active or dynamic hamstring-stretching exercises would reduce the amount of muscle damage observed after a strenuous eccentric task and to determine whether the stretching protocols elicit similar responses.
A randomized controlled clinical trial.
Thirty-six young male students performed 5 min of jogging as a warm-up and were allocated to 1 of 3 groups: 3 min of static active stretching (SAS), 3 min of dynamic active stretching (DAS), or control (CON). All subjects performed eccentric exercise immediately after stretching. Heart rate, core temperature, maximal voluntary isometric contraction, passive hip flexion, passive hamstring stiffness (PHS), plasma creatine kinase activity, and myoglobin were recorded at prestretching, at poststretching, and every day after the eccentric exercises for 5 d.
After stretching, the change in hip flexion was significantly higher in the SAS (5°) and DAS (10.8°) groups than in the CON (–4.1°) group. The change in PHS was significantly higher in the DAS (5.6%) group than in the CON (–5.7%) and SAS (–6.7%) groups. Furthermore, changes in muscle-damage markers were smaller in the SAS group than in the DAS and CON groups.
Prior active stretching could be useful for attenuating the symptoms of muscle damage after eccentric exercise. SAS is recommended over DAS as a stretching protocol in terms of strength, hamstring range of motion, and damage markers.
Anthea C. Clarke, Judith M. Anson and David B. Pyne
To examine relationships between on-field game movement patterns and changes in markers of neuromuscular fatigue and muscle damage during a 2-d women’s rugby sevens tournament.
Female national (mean ± SD n = 12, 22.3 ± 2.5 y, 1.67 ± 0.04 m, 65.8 ± 4.6 kg) and state (n = 10, 24.4 ± 4.3 y, 1.67 ± 0.03 m, 66.1 ± 7.9 kg) representative players completed baseline testing for lower-body neuromuscular function (countermovement-jump [CMJ] test), muscle damage (capillary creatine kinase [CK]), perceived soreness, and perceived recovery. Testing was repeated after games on days 1 and 2 of the tournament. GPS (5-Hz) data were collected throughout the tournament (4−6 games/player).
National players were involved in greater on-field movements for total time, distance, high-speed running (>5 m/s), and impacts >10 g (effect size [ES] = 0.55−0.97) and displayed a smaller decrement in performance from day 1 to day 2. Despite this, state players had a much greater 4-fold increase (ΔCK = 737 U/L) in CK compared with the 2-fold increase (ΔCK = 502 U/L) in national players (ES = 0.73). Both groups had similar perceived soreness and recovery while CMJ performance was unchanged. High-speed running and impacts >10 g were largely correlated (r = .66−.91) with ΔCK for both groups.
A 2-day women’s rugby sevens tournament elicits substantial muscle damage; however, there was little change in lower-body neuromuscular function. Modest increases in CK can largely be attributed to high-speed running and impacts >10 g that players typically endure.
Marco Machado, Alexander J. Koch, Jeffrey M. Willardson, Frederico C. dos Santos, Victor M. Curty and Lucas N. Pereira
The purpose of this study was to evaluate the effects of caffeine ingestion before a resistance exercise session on markers of muscle damage (CK, LDH, ALT, AST) and leukocyte levels.
Fifteen soccer athletes completed two resistance exercise sessions that differed only in the ingestion of caffeine or a placebo preworkout.
CK concentration increased significantly following the caffeine session (415.8 ± 62.8 to 542.0 ± 73.5) and the placebo session (411.5 ± 43.3 to 545.8 ± 59.9), with no significant differences between sessions. Similarly, LDH concentration increased significantly following the caffeine session (377.5 ± 18.0 to 580.5 ± 36.1) and the placebo session (384.8 ± 13.9 to 570.4 ± 36.1), with no significant differences between sessions. Both sessions resulted in significant increases in the total leukocyte count (caffeine = 6.24 ± 2.08 to 8.84 ± 3.41; placebo = 6.36 ± 2.34 to 8.77 ± 3.20), neutrophils (caffeine = 3.37 ± 0.13 to 5.15 ± 0.28; placebo = 3.46 ± 0.17 to 5.12 ± 0.24), lymphocytes (caffeine = 2.19 ± 0.091 to 2.78 ± 0.10; placebo = 2.17 ± 0.100 to 2.75 ± 0.11), and monocytes (caffeine = 0.53 ± 0.02 to 0.72 ± 0.06; placebo = 0.56 ± 0.03 to 0.69 ± 0.04), with no significant differences between sessions.
Ingestion of caffeine at 4.5 mg⋅kg-1 did not augment markers of muscle damage or leukocyte levels above that which occurs through resistance exercise alone.