Browse

You are looking at 81 - 90 of 5,165 items for :

  • Physical Education and Coaching x
  • Sport and Exercise Science/Kinesiology x
Clear All
Restricted access

Harry G. Banyard, James J. Tufano, Jonathon J.S. Weakley, Sam Wu, Ivan Jukic and Kazunori Nosaka

Purpose: To compare the effects of velocity-based training (VBT) and 1-repetition-maximum (1RM) percentage-based training (PBT) on changes in strength, loaded countermovement jump (CMJ), and sprint performance. Methods: A total of 24 resistance-trained males performed 6 weeks of full-depth free-weight back squats 3 times per week in a daily undulating format, with groups matched for sets and repetitions. The PBT group lifted with fixed relative loads varying from 59% to 85% of preintervention 1RM. The VBT group aimed for a sessional target velocity that was prescribed from pretraining individualized load–velocity profiles. Thus, real-time velocity feedback dictated the VBT set-by-set training load adjustments. Pretraining and posttraining assessments included the 1RM, peak velocity for CMJ at 30%1RM (PV-CMJ), 20-m sprint (including 5 and 10 m), and 505 change-of-direction test (COD). Results: The VBT group maintained faster (effect size [ES] = 1.25) training repetitions with less perceived difficulty (ES = 0.72) compared with the PBT group. The VBT group had likely to very likely improvements in the COD (ES = −1.20 to −1.27), 5-m sprint (ES = −1.17), 10-m sprint (ES = −0.93), 1RM (ES = 0.89), and PV-CMJ (ES = 0.79). The PBT group had almost certain improvements in the 1RM (ES = 1.41) and possibly beneficial improvements in the COD (ES = −0.86). Very likely favorable between-groups effects were observed for VBT compared to PBT in the PV-CMJ (ES = 1.81), 5-m sprint (ES = 1.35), and 20-m sprint (ES = 1.27); likely favorable between-groups effects were observed in the 10-m sprint (ES = 1.24) and nondominant-leg COD (ES = 0.96), whereas the dominant-leg COD (ES = 0.67) was possibly favorable. PBT had small (ES = 0.57), but unclear differences for 1RM improvement compared to VBT. Conclusions: Both training methods improved 1RM and COD times, but PBT may be slightly favorable for stronger individuals focusing on maximal strength, whereas VBT was more beneficial for PV-CMJ, sprint, and COD improvements.

Restricted access

Elena Pardos-Mainer, José Antonio Casajús, Chris Bishop and Oliver Gonzalo-Skok

Purpose: To examine the effects of an 8-week combined strength and power training intervention on physical performance and interlimb asymmetries in adolescent female soccer players. Methods: Thirty-seven adolescent female soccer players (age 16.1 [1.1] y) were randomly assigned to a control group (n = 18) or experimental group (n = 19). The experimental group performed combined strength and power training twice a week, which consisted of strength and power exercises that trained the major muscles of the lower body and trunk musculature. Preintervention and postintervention tests included unilateral and bilateral horizontal and countermovement jump tests, a 40-m sprint test (10- and 30-m split times), a 10-m sprint with a 180° change-of-direction (COD) test, and a multiple-COD test (V-cut test). Asymmetries were also analyzed in the unilateral tests. Results: Significant group-by-time interaction of the improvement between pretest and posttest was observed for speed (effect size [ES]: −1.30 to −1.16) and COD tests (ES: −0.62 to −0.61) but not in jumping (ES: −0.09 to 0.28) and interlimb-asymmetry tests (ES: −0.13 to 0.57). Conclusions: The short-term in-season combined strength and power training program induced greater speed and COD performance improvements than soccer training alone in adolescent female soccer players.

Restricted access

Evgeny B. Myakinchenko, Andrey S. Kriuchkov, Nikita V. Adodin and Victor Feofilaktov

Purpose: To compare the training-volume (TrV) distribution of Russian international-level male biathletes, female biathletes, and cross-country skiers (XC) during an annual cycle. Methods: Day-to-day TrVs were recorded and averaged for a 5-year period for male biathletes (n = 6), female biathletes (n = 8), and XC (n = 14) with VO2max values of 77.7 (3.8), 64.6 (1.9), and 79.4 (3.5) mL·min−1·kg−1, respectively. Results: The volumes of low- and moderate-intensity endurance training and all types of nonspecific endurance and strength training gradually decreased toward the competition period. However, the volumes and proportions of high-intensity endurance training and specific exercises (roller skiing, skiing, and shooting during high-intensity endurance training) increased by the time of the competition period. The total volume of training, volumes of low- and moderate-intensity endurance training, moderate- and high-load strength training (70%–95% 1RM), and power/speed loads did not increase gradually but reached their maximum immediately after a short stage of initial training. All teams employed the “pyramid” model of intensity distribution. Compared with the biathletes, XC demonstrated a larger (P < .01) annual volume of endurance training (~190 h), low-intensity endurance training (~183 h), and strength training (~818 sets). They also engaged in more upper-body and core-strength exercises (~769 sets), and they reached their maximum aerobic TrVs in June, while the biathletes reached theirs in July. Conclusions: In recent decades, the traditional model of periodization has been altered. The Russian XC and biathletes had significant differences in TrVs.

Restricted access

Jason Brumitt, Marcey Keefer Hutchison, Dan Kang, Zach Klemmer, Mike Stroud, Edward Cheng, Neil Patrick Cayanan and Sheldon Shishido

Context: Blood flow restriction (BFR) training utilizes a tourniquet, applied to the proximal portion of one or more extremities, to occlude blood flow during exercise. Significant gains in strength and cross-sectional area can be achieved in muscles, both distal and proximal to BFR cuff application. Purpose: To compare strength gains of the rotator cuff and changes in tendon size in subjects who performed side-lying external-rotation exercise with or without BFR. Methods: Forty-six subjects (mean age 25.0 [2.2] y) were randomized to either a BFR + exercise group or to the exercise-only group. Subjects performed 4 sets of the exercise (30/15/15/15 repetitions) at 30% 1-repetition maximum 2 days per week for 8 weeks. Results: Subjects in both groups experienced strength gains in the supraspinatus and the external rotators (P = .000, P = .000). However, there was no difference in strength gains between groups for the supraspinatus (P = .750) or the external rotators (P = .708). Subjects in both groups experienced increases in supraspinatus tendon thickness (BFR P = .041, exercise only P = .011). However, there was no difference between groups (P = .610). Conclusions: Exercise with BFR applied to the proximal upper extremity did not augment rotator cuff strength gains or tendon thickness when compared with subjects who only exercised. This study did demonstrate that performing multiple sets of high repetitions at a low load led to significant increases in rotator cuff strength and tendon size in the dominant upper extremity.

Restricted access

Daniel Boullosa, Marco Beato, Antonio Dello Iacono, Francisco Cuenca-Fernández, Kenji Doma, Moritz Schumann, Alessandro Moura Zagatto, Irineu Loturco and David G. Behm

Postactivation potentiation (PAP) mechanisms and responses have a long scientific history. However, to this day there is still controversy regarding the mechanisms underlying enhanced performance after a conditioning activity. More recently, the term postactivation performance enhancement (PAPE) has been proposed with differing associated mechanisms and protocols than with PAP. However, these 2 terms (PAP and PAPE) may not adequately describe all specific potentiation responses and mechanisms and can also be complementary, in some cases. Purpose: This commentary presents and discusses the similarities and differences between PAP and PAPE and, subsequently, elaborates on a new taxonomy for better describing performance potentiation in sport settings. Conclusion: The elaborated taxonomy proposes the formula “Post-[CONDITIONING ACTIVITY] [VERIFICATION TEST] potentiation in [POPULATION].” This taxonomy would avoid erroneous identification of isolated physiological attributes and provide individualization and better applicability of conditioning protocols in sport settings.

Restricted access

Anasthase Massamba, Stéphane P. Dufour, Fabrice Favret and Thomas J. Hureau

Purpose: The purpose of this study was to investigate the influence of the soccer pitch area during small-sided games (SSG) in prepubertal children on physiological and technical demands, and to compare them, for the physiological demands, to high-intensity interval training (HIIT). Methods: Ten young soccer players (13.0 [0.3] y) performed a HIIT and 3 SSG of various field sizes (30 × 20 m, 42 × 38 m, and 51 × 34 m). Each SSG was performed with 5 players per team, during 4 × 4-minutes interspaced with 1 minute of passive recovery in between. HIIT also followed a 4 × 4-minute protocol with running speed set on an individual basis. Heart rate (HR) was continuously monitored during training sessions. For each exercise modality, time spent above 90% of HRmax (T≥90%,HRmax) was calculated, and technical actions were quantified during SSG by video analysis. Results: T≥90%,HRmax was similar between the 3 SSG (∼587 [276] s; P > .2) but 24% to 37% lower than during HIIT (826 [140] s, P < .05). Coefficients of variations in T≥90%,HRmax were 2.3 to 3.5 times larger in SSG compared with HIIT. For technical actions, greater number of possessions (21 [6] vs ∼14 [4]), and lower ball touches per possession (2.4 [0.6] vs ∼2.9 [0.6]) were found in the small SSG compared with larger SSG, respectively (P < .05). Conclusion: The 3 SSG led to lower acute stimulation of the aerobic metabolism, suggesting a lower potential for chronic aerobic adaptations, compared with HIIT. Moreover, interindividual variability in the physiological response was substantially greater in SSG compared with HIIT, indicating increased heterogeneity among players performing the same training protocol.

Restricted access

Xabier Muriel, Javier Courel-Ibáñez, Victor Cerezuela-Espejo and Jesús G. Pallarés

Purpose: The COVID-19 outbreak has challenged professional athletes’ training and competition routines in a way not seen before. This report aims to inform about the changes in training volume and intensity distribution and their effects on functional performance due to a 7-week home-confinement period in professional road cyclists from a Union Cycliste Internationale Pro Team. Methods: A total of 18 male professional cyclists (mean [SD] age = 24.9 [2.8] y, body mass = 66.5 [5.6] kg, maximal aerobic power = 449 [39] W; 6.8 [0.6] W/kg) were monitored during the 10 weeks before the lockdown (outdoor cycling) and the 7-week lockdown (indoor cycling turbo trainer). Data from the mean maximal power output (in watts per kilogram) produced during the best 5-minute and best 20-minute records and the training intensity distributions (weekly volumes at power-based training zones) were collected from WKO5 software. Results: Total training volume decreased 33.9% during the lockdown (P < .01). Weekly volumes by standardized zones (Z1 to Z6) declined between 25.8% and 52.2% (effect size from 0.83 to 1.57), except for Z2 (P = .38). There were large reductions in best 5-minute and best 20-minute performance (effect size > 1.36; P < .001) with losses between 1% and 19% in all the cyclists. Conclusions: Total indoor volumes of 12 hours per week, with 6 hours per week at low intensity (Z1 and Z2) and 2 hours per week at high intensity over the threshold (Z5 and Z6), were insufficient to maintain performance in elite road cyclists during the COVID-19 lockdown. Such performance declines should be considered to enable a safe and effective return to competition.

Restricted access

Cristiano D. da Silva and Ric Lovell

Purpose: To examine the physiological, muscle-damage, endocrine, and immune responses to a modified soccer-simulation protocol to include technical and jumping activities characteristic of match play (the Technical Soccer-Specific Aerobic Field Test; T-SAFT90). Methods: Eighteen university players (age 23 [2] y, stature 175 [5] cm, body mass 74 [11] kg) performed the 90-minute protocol, with acute physiological responses monitored via heart rate, ratings of perceived exertion (6–20 scale), and body mass changes. Creatine kinase, myoglobin, cortisol, and leukocyte subset concentrations were measured at baseline, immediately (0 h), and 24 hours post T-SAFT90. Results: T-SAFT90 incurred an average heart rate equivalent to 87% (5%) of maximum, 16 (2) a.u. ratings of perceived exertion, and a 1.5% (1.0%) body mass deficit. Moderate to large proliferation of leukocyte subsets (P ≤ .01; leukocytes: 6.4-fold; neutrophils: 5.5-fold; lymphocytes: 2.0-fold) and increases in cortisol (2.3-fold) were observed at 0 hours (effect size = 1.13–3.52), each returning to baseline by 24 hours (P > .45; effect size = 0.05–0.50). Myoglobin peaked immediately post T-SAFT90 (4.8-fold), whereas creatine kinase (24 h: 6.0-fold) showed a delayed time course (both P ≤ .001; very large effects; effect size = 2.66 and 3.43, respectively). Conclusions: The magnitude and time course of the physiological, immune, endocrine, and muscle-damage markers observed during and following T-SAFT90 are similar to values reported in match-play literature, demonstrating external validity of the simulation.

Restricted access

Jordan L. Fox, Aaron T. Scanlan, Robert Stanton, Cody J. O’Grady and Charli Sargent

Purpose: To examine the impact of workload volume during training sessions and games on subsequent sleep duration and sleep quality in basketball players. Methods: Seven semiprofessional male basketball players were monitored across preseason and in-season phases to determine training session and game workloads, sleep duration, and sleep quality. Training and game data were collected via accelerometers, heart-rate monitors, and rating of perceived exertion (RPE) and reported as PlayerLoad (PL), summated heart-rate zones, and session RPE (sRPE). Sleep duration and sleep quality were measured using wrist-worn activity monitors in conjunction with self-report sleep diaries. For daily training sessions and games, all workload data were independently sorted into tertiles representing low, medium, and high workload volumes. Sleep measures following low, medium, and high workloads and control nights (no training/games) were compared using linear mixed models. Results: Sleep onset time was significantly later following medium and high PL and sRPE game workloads compared with control nights (P < .05). Sleep onset time was significantly later following low, medium, and high summated heart-rate-zones game workloads, compared with control nights (P < .05). Time in bed and sleep duration were significantly shorter following high PL and sRPE game workloads compared with control nights (P < .05). Following low, medium, and high training workloads, sleep duration and quality were similar to control nights (P > .05). Conclusions: Following high PL and sRPE game workloads, basketball practitioners should consider strategies that facilitate longer time in bed, such as napping and/or adjusting travel or training schedules the following day.

Restricted access

Thiago Oliveira Borges, Nicola Bullock, David Aitken, Gregory R. Cox and Aaron J. Coutts

Purpose: To compare the metabolic cost of paddling on different commercially available kayak ergometers using a standardized kayak incremental exercise protocol. Methods: Six male sprint kayak athletes undertook an incremental exercise protocol on 3 different kayak ergometers utilizing a randomized counterbalanced pair-matched design. Results: Mean maximal aerobic power on the WEBA ergometer (265 [14] W) was significantly higher than on the Dansprint (238 [9] W) and KayakPro® (247 [21] W, P < .01, effect size [ES] = 0.80). At the fifth stage, absolute oxygen consumption on the WEBA (3.82 [0.25] L·min−1) was significantly lower (P < 0.05, ES = 0.20) than KayakPro and Dansprint (4.10 [0.28] and 4.08 [0.27] L·min−1, respectively). Blood lactate concentration response at the sixth stage was significantly lower for the WEBA (3.5 [0.8] mmol·L−1), compared with KayakPro and Dansprint (5.4 [1.2] and 5.6 [1.5] mmol·L−1, P = .012, ES = 0.20). Stroke rate was significantly higher, without any effect of pacing during the submaximal stages for the Dansprint, compared with the WEBA (P < .001, ES = 0.28) and KayakPro (P < .001, ES = 0.38). A pacing effect was present at the maximal stage for all ergometers. Conclusions: This study demonstrated that paddling on different kayak ergometers when controlling power output elicits different metabolic and work outputs. It is recommended that scientists and coaches avoid testing on different ergometers and regularly calibrate these devices. Moreover, when an ergometer has been calibrated against a first principle device, it is necessary to consider calibration of various drag settings, due to their impact on stroke rate. Further research should explore the relationship between drag settings and stroke rate.