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Komar J.,Performance Laboratory | Komar J.,University of Rouen | Seifert L.,University of Rouen | Thouvarecq R.,University of Rouen
Movement and Sports Sciences - Science et Motricite | Year: 2015

In this review, we revisit the concept of movement variability in motor expertise from the perspective of complex systems theory; we do so by defining performers and their relationships with the environment. The complex systems perspective places the focus on the functional role of movement variability as an emergent response to interacting constraints as performers pursue task-goals. We therefore show how the shift in theoretical focus towards the functional role of variability has entailed a reconsideration of the way this key property of motor expertise should be assessed. We then present the main theoretical issues surrounding movement variability and expertise through examples of empirical applications of the relevant tools and concepts in the sport and movement sciences. © ACAPS, EDP Sciences, 2015.

Inoue A.,Estacio de Sa University | Inoue A.,Physical Education Center Admiral Adalberto Nunes | Inoue A.,Performance Laboratory | Inoue A.,University of Sao Paulo | And 10 more authors.
PLoS ONE | Year: 2016

Objectives The current study compared the effects of high-intensity aerobic training (HIT) and sprint interval training (SIT) on mountain biking (MTB) race simulation performance and physiological variables, including peak power output (PPO), lactate threshold (LT) and onset of blood lactate accumulation (OBLA). Methods Sixteen mountain bikers (mean ± SD: age 32.1 ± 6.4 yr, body mass 69.2 ± 5.3 kg and VO2max 63.4 ± 4.5 mL-kg-1-min-1) completed graded exercise and MTB performance tests before and after six weeks of training. The HIT (7-10 x [4-6 min-highest sustainable intensity / 4-6 min-CR100 10-15]) and SIT (8-12 x [30 s-all-out intensity / 4 min-CR100 10-15]) protocols were included in the participants' regular training programs three times per week. Results Post-training analysis showed no significant differences between training modalities (HIT vs. SIT) in body mass, PPO, LT or OBLA (p = 0.30 to 0.94). The Cohen's d effect size (ES) showed trivial to small effects on group factor (p = 0.00 to 0.56). The interaction between MTB race time and training modality was almost significant (p = 0.08), with a smaller ES in HIT vs. SIT training (ES = -0.43). A time main effect (pre- vs. post-phases) was observed in MTB race performance and in several physiological variables (p = 0.001 to 0.046). Co-variance analysis revealed that the HIT (p = 0.043) group had significantly better MTB race performance measures than the SIT group. Furthermore, magnitude-based inferences showed HIT to be of likely greater benefit (83.5%) with a lower probability of harmful effects (0.8%) compared to SIT. Conclusion The results of the current study suggest that six weeks of either HIT or SIT may be effective at increasing MTB race performance; however, HIT may be a preferable strategy. © 2016 Inoue et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Inoue A.,Gama Filho University | Inoue A.,Performance Laboratory | Safilho A.S.,Gama Filho University | Safilho A.S.,Performance Laboratory | And 4 more authors.
Journal of Strength and Conditioning Research | Year: 2012

Despite its apparent relevance, there is no evidence supporting the importance of anaerobic metabolism in Olympic crosscountry mountain biking (XCO). The purpose of this study was to examine the correlation between XCO race time and performance indicators of anaerobic power. Ten XCO riders (age: 28 6 5 years; weight: 68.7 ± 7.7 kg; height: 177.9 ± 7.4 cm; estimated body fat: 5.7 ± 2.8%; estimated VO2max: 68.4 ± 5.7 ml kg-1 min-1) participating in the Lagos Mountain Bike Championship (Brazil) completed 2 separate testing sessions before the race. In the first session, after anthropometric assessments were performed, the cyclists completed a single 30-second Wingate (WIN) test and an intermittent tests consisting of 5 × 30- second WIN tests (50% of the single WIN load) with 30 seconds of recovery between trials. In the second session, the riders performed a maximal incremental test. A significant correlation was found between race time and maximal power on the 5× WIN test (r = -0.79, IC 95% -0.94 to -0.32, p = 0.006) and the mean average power on the 5× WIN test normalized by body mass (r = -0.63, IC95% 20.90 to 20.01, p = 0.048). The finding of the study supports the use of anaerobic tests for assessing mountain bikers participating in XCO competitions and suggests that anaerobic power is an important determinant of performance. © 2012 National Strength and Conditioning Association.

Botton F.,Performance Laboratory | Botton F.,University of Lyon | Hautier C.,University of Lyon | Eclach J.-P.,Performance Laboratory
Journal of Strength and Conditioning Research | Year: 2011

The aim of this study was to estimate, using video analysis, what proportion of the total energy expenditure during a tennis match is accounted for by aerobic and anaerobic metabolism, respectively. The method proposed involved estimating the metabolic power (MP) of 5 activities, which are inherent to tennis: walking, running, hitting the ball, serving, and sitting down to rest. The energy expenditure concerned was calculated by sequencing the activity by video analysis. A bioenergetic model calculated the aerobic energy expenditure (EEO2mod) in terms of MP, and the anaerobic energy expenditure was calculated by subtracting this (MP 2 EEO2mod). Eight tennis players took part in the experiment as subjects (mean 6 SD: age 25.2 6 1.9 years, weight 79.3 6 10.8 kg, VO2max 54.4 6 5.1 ml-kg21-min21). The players started off by participating in 2 games while wearing the K4b2, with their activity profile measured by the video analysis system, and then by playing a set without equipment but with video analysis. There was no significant difference between calculated and measured oxygen consumptions over the 16 games (p = 0.763), and these data were strongly related (r = 0.93, p < 0.0001). The EEO2mod was quite weak over all the games (49.4 6 4.8% VO2max), whereas the MP during points was up to 2 or 3 times the VO2max. Anaerobic metabolism reached 32% of the total energy expenditure across all the games 67% for points and 95% for hitting the ball. This method provided a good estimation of aerobic energy expenditure and made it possible to calculate the anaerobic energy expenditure. This could make it possible to estimate the metabolic intensity of training sessions and matches using video analysis. © 2011 National Strength and Conditioning Association.

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