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Paul G. Montgomery and Will G. Hopkins

Australian Football is an intense team sport played over ~120 min on a weekly basis. To determine the effects of game and training load on muscle soreness and the time frame of soreness dissipation, 64 elite Australian Football players (age 23.8 ± 1.8 y, height 183.9 ± 3.8 cm, weight 83.2 ± 5.0 kg; mean ± SD) recorded perceptions of muscle soreness, game intensity, and training intensity on scales of 1–10 on most mornings for up to 3 competition seasons. Playing and training times were also recorded in minutes. Data were analyzed with a mixed linear model, and magnitudes of effects on soreness were evaluated by standardization. All effects had acceptably low uncertainty. Game and training-session loads were 790 ± 182 and 229 ± 98 intensity-minutes (mean ± SD), respectively. General muscle soreness was 4.6 ± 1.1 units on d 1 postgame and fell to 1.9 ± 1.0 by d 6. There was a small increase in general muscle soreness (0.22 ± 0.07–0.50 ± 0.13 units) in the 3 d after high-load games relative to low-load games. Other soreness responses showed similar timelines and magnitudes of change. Training sessions made only small contributions to soreness over the 3 d after each session. Practitioners should be aware of these responses when planning weekly training and recovery programs, as it appears that game-related soreness dissipates after 3 d regardless of game load and increased training loads in the following week produce only small increases in soreness.

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Darrell L. Bonetti and Will G. Hopkins

Purpose:

To estimate variability in performance time and smallest worthwhile changes for elite fat-water canoeists competing in 200-, 500- or 1000-m events at international regattas.

Methods:

The data came from A and B finals held at 7 to 13 regattas in 2003 to 2007. A linear mixed-model analysis of log-transformed official race times provided estimates of variability as coefficients of variation and included terms to account for changes in performance between years, venues, and A and B finals.

Results:

For men, the within-athlete variation in A finals was similar in canoeing and kayaking events, with the 200-m men’s events demonstrating probably less variability than the longer events (by an overall factor of 0.75, ×/÷1.33) that may reflect differences in pacing strategies. In contrast, the within-athlete variation for women kayakers in A finals of the 500-m event was only half that of the other distances (ratio 0.54, ×/÷1.29), possibly because of differences in competitive experience or depth of competition. Predictability of performance in A finals was moderate to very high (interclass correlations 0.40 to 0.89). Within-athlete variation in the B finals was generally greater than in the A finals for the three distances for men, but there was no clear pattern for women.

Conclusion:

The smallest worthwhile changes in performance time (0.3× within-athlete variability) in canoeing and kayaking are approx. 0.3% to 0.6%. Effects of 1% to 2% in power output would be required to achieve such changes in this generally highly predictable sport.

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Kathryn E. Phillips and Will G. Hopkins

Purpose: To further the understanding of elite athlete performance in complex race environments by examining the changes in cyclists’ performance between solo time trials and head-to-head racing in match-sprint tournaments. Methods: Analyses were derived from official results of cyclists in 61 elite international sprint tournaments (2000–2016), incorporating the results of 2060 male and 1969 female head-to-head match races. Linear mixed modeling of log-transformed qualification and finish ranks was used to determine estimates of performance predictability as intraclass correlation coefficients. Correlations between qualifying performance and final tournament rank were also calculated. Chances of winning head-to-head races were estimated adjusting for the difference in the cyclists’ qualifying times. All effects were evaluated using magnitude-based inference. Results: Minor differences in predictability between qualification time trial and final tournament rank were suggestive of more competitiveness among men in the overall tournament. Performance in the qualification time trial was strongly correlated with, but not fully indicative of, performance in the overall tournament. Correspondingly, being the faster qualifier had a large positive effect on the chances of winning a head-to-head race, but small substantial differences between riders remained after adjustment for time-trial differentials. Conclusions: The present study provides further insight into how real-world competition data can be used to investigate elite athlete performance in sports where athletes must directly interact with their opponents. For elite match-sprint cyclists, qualifying time-trial performance largely determines success in the overall tournament, but there is evidence of a consistent match-race ability that modifies the chances of winning head-to-head races.

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David K. Liow and Will G. Hopkins

The training practices of athletes with disabilities were investigated by means of a validated self-administered questionnaire. Descriptive statistics were derived from the replies of 41 wheelchair racers, 20 swimmers, and 14 athletes specializing in throwing events. The majority of athletes competed at either international (77%) or national levels (15%). Almost all swimmers were coached frequently, but one third of the wheelchair racers and one half of the throwers were not coached. Median volumes of endurance, interval, strength, and skill training in each of four training phases (buildup, precompetition, taper, and postcompetition) only partially reflected the contribution of energy systems and skills to performance in the different sports; moreover, there were wide variations in the training programs of athletes within each sport, especially swimmers and throwers. It was concluded that there is need for improvement in the coaching and training of many top-class athletes with disabilities.

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Will G. Hopkins and Alan M. Batterham

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Kathryn E. Phillips and Will G. Hopkins

Purpose:

To explore the extent to which factors that determine performance transfer within and between time-trial and mass-start events in the track-cycling Omnium.

Methods:

Official finish rank in the 3 time-trial events, in the 3 mass-start events, and in the competition overall were collated in 20 international Omnium competitions between 2010 and 2014 for 196 male and 140 female cyclists. Linear mixed modeling of the log-transformed finish time for the time-trial events and of log-transformed finish rank for all events and final rank provided estimates of within-athlete race-to-race changes in performance and average betweenathletes differences across a season. These estimates were converted to various correlations representing relationships within and between the various events and final rank.

Results:

Intraclass correlation coefficients, representing race-to-race reproducibility of performance, were similar whether derived from finish rank or finish time for the time-trial events. Log-transformed finish ranks are therefore a suitable measure to assess and compare performance in time-trial and mass-start events. Omnium cyclists were more predictable in their performances from race to race in the timed events, whereas reduced predictability was observed in mass-start events. Interevent correlations indicated stronger links in performance between the timed disciplines, whereas performance in any of the mass-start events had only a slight positive relationship with performance in the other massstart events and little or no relationship with the timed events.

Conclusions:

Further investigation is warranted to determine whether factors related to performance in mass-start events can be identified to improve reproducibility or whether variability in performance results from random chance.

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David S. Rowlands and Will G. Hopkins

The effect of pre-exercise meal composition on metabolism and performance in cycling were investigated in a crossover study. Twelve competitive cyclists ingested high-fat, high-carbohydrate, or high-protein meals 90 min before a weekly exercise test. The test consisted of a 1-hour pre-load at 55% peak power, five 10-min incremental loads from 55 to 82% peak power (to measure the peak fat-oxidation rate), and a 50-km time trial that included three 1-km and 4-km sprints. A carbohydrate supplement was ingested throughout the exercise. Relative to the high-protein and high-fat meals, the high-carbohydrate meal halved the peak fat-oxidation rate and reduced the fat oxidation across all workloads by a factor of 0.20 to 0.58 (p = .002–.0001). Reduced fat availability may have accounted for this reduction, as indicated by lower plasma fatty acid, lower glycerol, and higher pre-exercise insulin concentrations relative to the other meals (p = .04–.0001). In contrast, fat oxidation following the high-protein meal was similar to that following the high-fat meal. This similarity was linked to evidence suggesting greater lipolysis and plasma fat availability following high-protein relative to high-carbohydrate meals. Despite these substantial effects on metabolism, meal composition had no clear effect on sprint or 50-km performance.

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Fabio R. Serpiello and Will G. Hopkins

Purpose: To assess the convergent validity of internal load measured with the CR100 scale in youth football players of 3 age groups. Methods: A total of 59 players, age 12–17 years, from the youth academy of a professional football club were involved in this study. Convergent validity was examined by calculating the correlation between session ratings of perceived exertion (sRPE) and Edwards load, a commonly used load index derived from the heart rate, with the data originating from 1 competitive season. The magnitude of the relationship between sRPE and Edwards load was obtained with weighted mean correlations and by assessing the effect of the change of the Edwards load on sRPE. Differences between the individuals’ intercepts and slopes were assessed by interpreting the SD representing the random effects (player identity and the interaction of player identity and scaled Edwards load). Probabilistic decisions about true (infinite sample) magnitudes accounting for sampling uncertainty were based on 1-sided hypothesis tests of substantial magnitudes, followed by reference Bayesian analysis. Results: Very high relationships exist between the sRPE and Edwards load across all age groups, with no meaningful differences in the magnitudes of the relationships between groups. Moderate to large differences between training sessions and games were found in the slopes of the relationships between the sRPE and Edwards load in all age groups. Finally, mostly small to moderate differences were observed between individuals for the intercepts and slopes of the relationships between the sRPE and Edwards load. Conclusion: Practitioners working in youth team sports can safely use the CR100 scale to track internal load.

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Andrea J. Braakhuis, Will G. Hopkins and Timothy E. Lowe

The beneficial effects of exercise and a healthy diet are well documented in the general population but poorly understood in elite athletes. Previous research in subelite athletes suggests that regular training and an antioxidant-rich diet enhance antioxidant defenses but not performance.

Purpose:

To investigate whether habitual diet and/or exercise (training status or performance) affect antioxidant status in elite athletes.

Methods:

Antioxidant blood biomarkers were assessed before and after a 30-min ergometer time trial in 28 male and 34 female rowers. The antioxidant blood biomarkers included ascorbic acid, uric acid, total antioxidant capacity (TAC), erythrocyte- superoxide dismutase, glutathione peroxidase (GPx), and catalase. Rowers completed a 7-d food diary and an antioxidant-intake questionnaire. Effects of diet, training, and performance on resting biomarkers were assessed with Pearson correlations, and their effect on exercise-induced changes in blood biomarkers was assessed by a method of standardization.

Results:

With the exception of GPx, there were small to moderate increases with exercise for all markers. Blood resting TAC had a small correlation with total antioxidant intake (correlation .29; 90% confidence limits, ±.27), and the exercise-induced change in TAC had a trivial to small association with dietary antioxidant intake from vitamin C (standardized effect .19; ±.22), vegetables (.20; ±.23), and vitamin A (.25; ±.27). Most other dietary intakes had trivial associations with antioxidant biomarkers. Years of training had a small inverse correlation with TAC (−.32; ±.19) and a small association with the exercise-induced change in TAC (.27; ±.24).

Conclusion:

Training status correlates more strongly with antioxidant status than diet does.

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Cesar Marius Meylan, John Cronin, Will G. Hopkins and Jonathan Oliver

Adjustment for body mass and maturation of strength, power, and velocity measures of young athletes is important for talent development. Seventy-four youth male athletes performed a ballistic leg press test at five loads relative to body mass. The data were analyzed in maturity groups based on years from peak height velocity: −2.5 to −0.9 y (n = 29); −1.0 to 0.4 y (n = 28); and 0.5 to 2.0 y (n = 16). Allometric scaling factors representing percent difference in performance per percent difference in body mass were derived by linear regression of log-transformed variables, which also permitted adjustment of performance for body mass. Standardized differences between groups were assessed via magnitude-based inference. Strength and power measures showed a greater dependency on body mass than velocity-related variables (scaling factors of 0.56–0.85 vs. 0.42–0.14%/%), but even after adjustment for body mass most differences in strength and power were substantial (7–44%). In conclusion, increases in strength and power with maturation are due only partly to increases in body mass. Such increases, along with appropriate adjustment for body mass, need to be taken into account when comparing performance of maturing athletes.