Caffeine Supplementation and Reactive Agility in Elite Youth Soccer Players

2014 ◽  
Vol 26 (2) ◽  
pp. 168-176 ◽  
Author(s):  
J. Bradley Jordan ◽  
Ajit Korgaokar ◽  
Richard S. Farley ◽  
John M. Coons ◽  
Jennifer L. Caputo
Keyword(s):  
Repeated Measures ◽  
Perceived Exertion ◽  
Soccer Players ◽  
Ratings Of Perceived Exertion ◽  
Double Blind ◽  
Male Youth ◽  
Warm Up ◽  
Youth Soccer ◽  
Repeated Measures Design ◽  
Reactive Agility

This study examined the effects of caffeine supplementation (6 mg·kg−1) on performance of a reactive agility test (RAT) in 17 elite, male, youth (M = 14 y) soccer players. Using a double-blind, repeated-measures design, players completed 4 days of testing on the RAT after a standardized warm-up. On day 1, anthropometric measurements were taken and players were accommodated to the RAT. On day 2, baseline performance was established. Caffeine or placebo conditions were randomly assigned on day 3 and the condition was reversed on day 4. Players completed 3 randomized trials of the RAT on days 2, 3, and 4 with at least 1 trial to the players’ dominant and nondominant sides. There were no significant differences among conditions in reaction time (RT) to the dominant side, heart rates at any point of measurement, or ratings of perceived exertion (RPE) after completion of the warm-up. Caffeine produced faster RT to the nondominant side (P = .041) and higher RPE at the conclusion of the RAT (P = .013). The effect on the total time (TT) to complete the agility test to the nondominant side approached significance (P = .051). Sprint time and TT to either side did not differ. Caffeine supplementation may provide ergogenic benefit to elite, male, youth soccer players.

A Mental Warm-Up for Athletes

2019 ◽  
Vol 33 (3) ◽  
pp. 213-220 ◽  
Author(s):  
Britton W. Brewer ◽  
Adisa Haznadar ◽  
Dylan Katz ◽  
Judy L. Van Raalte ◽  
Albert J. Petitpas
Keyword(s):  
Goal Setting ◽  
Repeated Measures ◽  
Soccer Players ◽  
Mental Skills ◽  
Male Youth ◽  
Warm Up ◽  
Youth Soccer ◽  
Competitive Season ◽  
Self Talk ◽  
Male High School

The purpose of this research was to develop and evaluate a 5-min structured mental warm-up involving aspects of goal setting, imagery, arousal regulation, and positive self-talk. Results of a study that featured a pretest–posttest design with 101 male youth soccer players (Study 1) and a study that featured a repeated-measures experimental design with 29 female intercollegiate soccer players (Study 2) indicated that executing the mental warm-up was associated with significantly greater readiness to perform and to use mental skills to enhance performance. In Study 3, 30 male high school soccer players used the mental warm-up daily over a competitive season and rated it as acceptable (albeit less so than their physical warm-up) at the beginning, in the middle, and at the end of the season. The findings suggest that a mental warm-up is both acceptable to athletes and potentially useful in helping them prepare for training and competition.

Use of Numerically Blinded Ratings of Perceived Exertion in Soccer: Assessing Concurrent and Construct Validity

2020 ◽  
Vol 15 (10) ◽  
pp. 1430-1436
Author(s):  
Ric Lovell ◽  
Sam Halley ◽  
Jason Siegler ◽  
Tony Wignell ◽  
Aaron J. Coutts ◽  
...  
Keyword(s):  
Construct Validity ◽  
Confidence Intervals ◽  
Repeated Measures ◽  
External Load ◽  
Perceived Exertion ◽  
Verbal Response ◽  
Ratings Of Perceived Exertion ◽  
Male Youth ◽  
Youth Soccer ◽  
External Loads

Purpose: To examine the concurrent and construct validity of numerically blinded ratings of perceived exertion (RPEs). Methods: A total of 30 elite male youth soccer players (age 16.7 [0.5] y) were monitored during training and matches over a 17-wk in-season period. The players’ external loads were determined via raw 10-Hz global positioning system. Heart rate (HR) was collected continuously and expressed as Bannister and Edwards training impulses, and minutes >80% of the players predetermined the maximum HR by the Yo-Yo Intermittent Recovery Test Level 1. RPE was collected confidentially 10 to 15 min after training/matches using 2 methods: (1) a traditional verbal response to the 0 to 100 category-ratio “centiMax” scale (RPE) and (2) numerically blinded RPE centiMax scale (RPEblind) with the response selected manually via a 5 × 7-in tablet “slider.” The RPE and RPEblind were divided by 10 and multiplied by the duration to derive the sessional RPE. Linear mixed models compared ratings, and within-subject repeated-measures correlations assessed the sessional RPE versus HR and external load associations. Results: There were no differences between the RPE and RPEblind (0.19; 95% confidence intervals, −0.59 to 0.20 au, P = .326) or their session values (13.5; 95% confidence intervals, −17.0 to 44.0 au, P = .386), and the ratings were nearly perfectly correlated (r = .96). The associations between the sessional RPE versus HR and external load metrics were large to very large (r = .65–.81), with no differences between the RPE methods (P ≥ .50). The RPEblind also reduced verbal anchor clustering and integer bias by 11% and 50%, respectively. Conclusions: RPEblind demonstrated concurrent and construct validity versus the traditional method, and may be used in situations where practitioners have concerns regarding the authenticity of athlete ratings.

Effect of the FIFA 11+ on Landing Patterns and Baseline Movement Errors in Elite Male Youth Soccer Players

2020 ◽  
Vol 29 (6) ◽  
pp. 730-737 ◽  
Author(s):  
Hadi Akbari ◽  
Mansour Sahebozamani ◽  
Ablolhamid Daneshjoo ◽  
Mohammadtaghi Amiri-Khorasani ◽  
Yohei Shimokochi
Keyword(s):  
Anterior Cruciate Ligament ◽  
Cruciate Ligament ◽  
Soccer Players ◽  
Control Group ◽  
Ligament Injuries ◽  
Male Youth ◽  
Warm Up ◽  
Youth Soccer ◽  
Anterior Cruciate Ligament Injuries ◽  
Anterior Cruciate

Context: There is no evidence regarding the effect of the FIFA 11+ on landing kinematics in male soccer players, and few studies exist regarding the evaluating progress of interventions based on the initial biomechanical profile. Objective: To investigate the effect of the FIFA 11+ program on landing patterns in soccer players classified as at low or high risk for noncontact anterior cruciate ligament injuries. Design: Randomized controlled trial. Setting: Field-based functional movement screening performed at the soccer field. Participants: A total of 24 elite male youth soccer players participated in this study. Intervention: The intervention group performed the FIFA 11+ program 3 times per week for 8 weeks, whereas the control group performed their regular warm-up program. Main Outcome Measures: Before and after the intervention, all participants were assessed for landing mechanics using the Landing Error Scoring System. Pretraining Landing Error Scoring System scores were used to determine risk groups. Results: The FIFA 11+ group had greater improvement than the control group in terms of improving the landing pattern; there was a significant intergroup difference (F1,20 = 28.86, P < .001, ). Soccer players categorized as being at high risk displayed greater improvement from the FIFA 11+ program than those at low risk (P = .03). However, there was no significant difference in the proportion of risk category following the routine warm-up program (P = 1.000). Conclusions: The present study provides evidence of the usefulness of the FIFA 11+ program for reducing risk factors associated with noncontact anterior cruciate ligament injuries. The authors’ results also suggest that soccer players with the higher risk profile would benefit more than those with lower risk profiles and that targeting them may improve the efficacy of the FIFA 11+ program.

scholarly journals Changes in Injury Risk Mechanisms After Soccer-Specific Fatigue in Male Youth Soccer Players

2018 ◽  
Vol 62 (1) ◽  
pp. 33-42 ◽  
Author(s):  
Michal Lehnert ◽  
Mark De Ste Croix ◽  
Zuzana Xaverova ◽  
Michal Botek ◽  
Renata Varekova ◽  
...  
Keyword(s):  
Injury Risk ◽  
Perceived Exertion ◽  
Metabolic Response ◽  
Body Height ◽  
Soccer Players ◽  
Hamstring Injury ◽  
Match Play ◽  
Male Youth ◽  
Youth Soccer ◽  
Specific Protocol

AbstractThe aim of this study was to examine the acute effects of soccer specific fatigue on muscular and neuromuscular function in male youth soccer players. Elite soccer players (n = 20; age 15.7 ± 0.5 y; body height 177.75 ± 6.61 cm; body mass 67.28 ± 8.29 kg) were measured before and after soccer specific exercise (SAFT90). The reactive strength index (RSI) was determined by a drop jump test, leg stiffness (LS) by a 20 sub-maximal two-legged hopping test, and a functional hamstring to quadriceps strength ratio from isokinetic concentric and eccentric strength of the dominant and non-dominant leg (measured at angular velocities of 1.05 rad · s−1and 3.14 rad · s−1). Metabolic response to the SAFT90was determined by blood lactate and perceived exertion was assessed by the Borg scale. After simulated match play, a significant decrease in absolute LS (t = 4.411; p < 0.001; ω2= 0.48) and relative LS (t = 4.326; p < 0.001; ω2= 0.49) was observed and the RSI increased significantly (t = 3.806; p = 0.001; ω2= 0.40). A reduction in LS found after the SAFT90indicates possible reduction in dynamic knee stabilization. However, if we consider the changes in other observed variables, the present study did not clearly confirm that fatigue induced by a soccer specific protocol increased the risk of ACL and hamstring injury. This may be attributed to the simulated rather than actual match play used in the present study.

Accumulative Weekly External and Internal Load Relative to Match Load in Elite Male Youth Soccer Players

2021 ◽  
pp. 1-6
Author(s):  
Vicente de Dios-Álvarez ◽  
Pello Alkain ◽  
Julen Castellano ◽  
Ezequiel Rey
Keyword(s):  
Global Positioning System ◽  
High Speed ◽  
Perceived Exertion ◽  
Soccer Players ◽  
Positioning System ◽  
Internal Load ◽  
Male Youth ◽  
Youth Soccer ◽  
Total Distance ◽  
Global Positioning

Purpose: The aim of this study was 2-fold: (1) to assess and compare the external and internal load of elite young soccer players during competitive microcycles and (2) to describe the training/match ratios (TMr) in elite male youth soccer players. Method: Twenty-one youth soccer players were monitored using a 10-Hz global positioning system. Total distance covered, running distance (RD), high-speed RD, sprint distance, number of accelerations and decelerations, player load, and rated perceived exertion were recorded during training sessions and matches. The TMr was calculated for each load measure. All variables were also normalized dividing the load per minute of activity. Results: The RD, high-speed running, and sprint distance were higher 3 days before the match and 2 days before match compared with the rest of the training sessions. However, accelerations, decelerations, and player load were higher 4 days before match than other sessions. Besides this, the TMr of RD, high-speed running, and sprint distance were associated with lower values than the TMr of total distance covered, accelerations, decelerations, and player load. The match constituted the highest load during competitive microcycle. Conclusions: The present data support the idea that youth soccer coaches and practitioners must consider relative training load according to match demands to better manage and evaluate player periodization.

Effect of Various Carbohydrate-Electrolyte Fluids on Cycling Performance and Maximal Voluntary Contraction

2010 ◽  
Vol 20 (2) ◽  
pp. 104-114 ◽  
Author(s):  
Matthew S. Ganio ◽  
Jennifer F. Klau ◽  
Elaine C. Lee ◽  
Susan W. Yeargin ◽  
Brendon P. McDermott ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Maximal Voluntary Contraction ◽  
Perceived Exertion ◽  
Cycling Performance ◽  
Voluntary Contraction ◽  
Rating Of Perceived Exertion ◽  
Total Work ◽  
Double Blind ◽  
Repeated Measures Design ◽  
The Central Nervous System

The purpose of this study was to compare the effects of a carbohydrate-electrolyte plus caffeine, carnitine, taurine, and B vitamins solution (CE+) and a carbohydrate-electrolyte-only solution (CE) vs. a placebo solution (PLA) on cycling performance and maximal voluntary contraction (MVC). In a randomized, double-blind, crossover, repeated-measures design, 14 male cyclists (M ± SD age 27 ± 6 yr, VO2max 60.4 ± 6.8 ml · kg−1 · min−1) cycled for 120 min submaximally (alternating 61% ± 5% and 75% ± 5% VO2max) and then completed a 15-min performance trial (PT). Participants ingested CE+, CE, or PLA before (6 ml/kg) and every 15 min during exercise (3 ml/kg). MVC was measured as a single-leg isometric extension (70° knee flexion) before (pre) and after (post) exercise. Rating of perceived exertion (RPE) was measured throughout. Total work accumulated (KJ) during PT was greater (p < .05) in CE+ (233 ± 34) than PLA (205 ± 52) but not in CE (225 ± 39) vs. PLA. MVC (N) declined (p < .001) from pre to post in PLA (988 ± 213 to 851 ± 191) and CE (970 ± 172 to 870 ± 163) but not in CE+ (953 ± 171 to 904 ± 208). At Minutes 60, 90, 105, and 120 RPE was lower in CE+ (14 ± 2, 14 ± 2, 12 ± 1, 15 ± 2) than in PLA (14 ± 2, 15 ± 2, 14 ± 2, 16 ± 2; p < .001). CE+ resulted in greater total work than PLA. CE+, but not PLA or CE, attenuated pre-to-post MVC declines. Performance increases during CE+ may have been influenced by lower RPE and greater preservation of leg strength during exercise in part as a result of the hypothesized effects of CE+ on the central nervous system and skeletal muscle.

scholarly journals Metabolic effects of a caffeinated sports drink consumed during a soccer match

2013 ◽  
Vol 19 (4) ◽  
pp. 688-695
Author(s):  
Ana Paula Muniz Guttierres ◽  
Rita de Cássia Alfenas ◽  
Karolina Gatti ◽  
Jorge Roberto Perrout Lima ◽  
Ângela Antunes Silva ◽  
...  
Keyword(s):  
Perceived Exertion ◽  
Potassium Concentration ◽  
Plasma Potassium ◽  
Metabolic Effects ◽  
Soccer Players ◽  
Maximum Heart Rate ◽  
Double Blind ◽  
Youth Soccer ◽  
Sports Drink ◽  
Plasmatic Concentration

The purpose of this study was to verify the effect of the intake of a caffeinated sport drink (CAFD) compared to a commercial carbohydrate drink (CHOD) on biochemical parameters and rate of perception exertion in youth soccer players. The experiment was setup in a double-blind crossover design where athletes consumed 5mL.Kg-1 body weight (BW) before the game and 3mL.Kg-1 BW every 15 minutes during the game. Intake of the CAFD resulted in increased blood glucose (BG) and blood lactate (BL) levels and average of maximum heart rate compared to consumption of the CHOD (p = 0.01). No difference was observed in the other variables. CAFD promoted greater plasmatic concentration of BG and BL compared with the CHOD. The CAFD did not increase the mobilization of free fatty acids, did not alter the plasma potassium concentration and was not able to reduce subjective perceived exertion.

Sodium Bicarbonate Supplementation Does Not Improve Running Anaerobic Sprint Test Performance in Semiprofessional Adolescent Soccer Players

2020 ◽  
Vol 30 (5) ◽  
pp. 330-337
Author(s):  
Rodrigo dos Santos Guimarães ◽  
Alcides Correa de Morais Junior ◽  
Raquel Machado Schincaglia ◽  
Bryan Saunders ◽  
Gustavo Duarte Pimentel ◽  
...  
Keyword(s):  
Sodium Bicarbonate ◽  
Muscle Fatigue ◽  
Perceived Exertion ◽  
Sprint Performance ◽  
Soccer Players ◽  
Fatigue Index ◽  
Countermovement Jump ◽  
Ratings Of Perceived Exertion ◽  
Double Blind ◽  
Repeated Sprint

Ergogenic strategies have been studied to alleviate muscle fatigue and improve sports performance. Sodium bicarbonate (NaHCO3) has improved repeated sprint performance in adult team-sports players, but the effect for adolescents is unknown. The aim of the present study was to evaluate the effect of NaHCO3 supplementation on repeated sprint performance in semiprofessional adolescent soccer players. In a double-blind, placebo-controlled, crossover trial, 15 male semiprofessional adolescent soccer players (15 ± 1 years; body fat 10.7 ± 1.3%) ingested NaHCO3 or a placebo (sodium chloride) 90 min before performing the running anaerobic sprint test (RAST). A countermovement jump was performed before and after the RAST, and ratings of perceived exertion, blood parameters (potential hydrogen and bicarbonate concentration), and fatigue index were also evaluated. Supplementation with NaHCO3 promoted alkalosis, as demonstrated by the increase from the baseline to preexercise, compared with the placebo (potential hydrogen: +0.07 ± 0.01 vs. −0.00 ± 0.01, p < .001 and bicarbonate: +3.44 ± 0.38 vs. −1.45 ± 0.31 mmol/L, p < .001); however, this change did not translate into an improvement in RAST total time (32.12 ± 0.30 vs. 33.31 ± 0.41 s, p = .553); fatigue index (5.44 ± 0.64 vs. 6.28 ± 0.64 W/s, p = .263); ratings of perceived exertion (7.60 ± 0.33 vs. 7.80 ± 0.10 units, p = .525); countermovement jump pre-RAST (32.21 ± 3.35 vs. 32.05 ± 3.51 cm, p = .383); or countermovement jump post-RAST (31.70 ± 0.78 vs. 32.74 ± 1.11 cm, p = .696). Acute NaHCO3 supplementation did not reduce muscle fatigue or improve RAST performance in semiprofessional adolescent soccer players. More work assessing supplementation in this age group is required to increase understanding in the area.

Effects of Caffeine on Repetitions to Failure and Ratings of Perceived Exertion During Resistance Training

2007 ◽  
Vol 2 (3) ◽  
pp. 250-259 ◽  
Author(s):  
J. Matt Green ◽  
P. Jason Wickwire ◽  
John R. McLester ◽  
Shawn Gendle ◽  
Geoffrey Hudson ◽  
...  
Keyword(s):  
Resistance Training ◽  
High Intensity ◽  
Repeated Measures ◽  
Perceived Exertion ◽  
Training Session ◽  
Mechanisms Of Action ◽  
Ratings Of Perceived Exertion ◽  
Double Blind ◽  
Significant Difference ◽  
Ergogenic Effects

Context:Ergogenic effects of caffeine on aerobic or endurance exercise are well documented. Conversely, the ergogenic value of caffeine on high-intensity, primarily anaerobic performance is not well understood even though the proposed mechanisms of action for caffeine permit a strong theoretical basis for application to this type of exercise.Purpose:This study examined effects of caffeine (Ca) on number repetitions (reps), ratings of perceived exertion (RPE), and peak heart rate (PHR) during resistance-training exercise with reps performed to volitional failure.Methods:Subjects (N = 17) were tested for 10-rep maximum in bench press (BP) and leg press (LP). In sessions 2 and 3, Ca (~6 mg/kg) or placebo (Pl) was ingested 1 hr beforehand in a double-blind manner and counterbalanced order. Subjects performed 3 sets to failure (BP and LP) with reps, PHR, and RPE recorded each set. Repeated-measures ANOVAs, 2 (trial) × 3 (set), were used to analyze dependent measures with the Tukey honestly significant difference used when necessary as the post hoc test.Results:In BP, no significant differences (Ca vs Pl) were observed (reps, RPE, PHR). During set 3 of LP training, Ca was associated with significantly higher reps (12.5 ± 4.2 vs 9.9 ± 2.6) and PHR (158.5 ± 11.9 vs 151.8 ± 13.2). No signifcant RPE differences were found during LP.Conclusions:The findings of similar RPE concurrent with higher reps suggest that caffeine can blunt pain responses, possibly delaying fatigue in high-intensity resistance training. Ergogenic effects might be limited to the later sets in a resistance-training session. Further research is warranted regarding ergogenic effects of caffeine during resistance training and potential mechanisms of action.

scholarly journals Acute Effects on Physical Performance Measures after 45 Min of Official Competition in Youth Soccer Players

2021 ◽  
Vol 6 (2) ◽  
pp. 49
Author(s):  
Federico Gazzo ◽  
Julián Giráldez ◽  
Rodrigo Villaseca-Vicuña ◽  
José Antonio González-Jurado ◽  
Santiago Zabaloy
Keyword(s):  
Physical Performance ◽  
Perceived Exertion ◽  
Study Data ◽  
Soccer Players ◽  
Acute Effects ◽  
Jump Performance ◽  
Warm Up ◽  
Youth Soccer ◽  
Performance Variables ◽  
Two Stages

(1) Background: An improved understanding of soccer players’ match-related physical performance and recovery may help conditioning programs and re-warm up strategies to increase team performance during official competitions. Therefore, the aim of this study was to analyze the acute effects of 45 min of official competition (first half in matches) on physical performance variables in U-16 youth soccer players. (2) Methods: 20 male soccer players (age: 14.4 ± 0.5 years; height: 1.70 ± 0.05 cm; body mass: 65.1 ± 11.6 kg) were recruited to participate in this study. Data was collected from five official matches. Participants performed the assessments in two stages of each match: after the pre-match warm-up and after the first half. Tests included rate of perceived exertion (RPE), 30-m sprint and countermovement (CMJ). (3) Results: Statistically significant differences were found (p < 0.001) when the measurements prior to the game were compared with those recorded after half time across all variables. Effect sizes (ES) were very large for RPE (ES = 1.82), moderate for 30-m sprint times (ES = 0.64) and small for CMJ (ES = −0.25). (4) Conclusions: After 45 min of official competition, our results suggest that U-16 soccer players demonstrated a reduction in sprint and jump performance, in addition to a higher RPE. Hence, this information could be useful when designing re-warming strategies that can be performed before the second half.

Sign in / Sign up

Export Citation Format

Share Document