The aims of this study were (a) to establish a specific endurance test procedure for competitive tennis players, combining performance, physiological and technical parameters and (b) to determine the relationship between these parameters and their competitive levels. Thirty-eight competitive male tennis players (age, 18.2 ± 1.3 years; height, 180 ± 0.08 cm; body mass, 72.7 ± 8.6 kg; mean ± SD) performed a specific endurance field test. Performance (level achieved), physiological (heart rate, maximum oxygen uptake (VO2max), and ventilatory thresholds (VT1, VT2), and technical parameters (technical effectiveness [TE]) were assessed. Bivariate and multivariate models for predicting performance level were developed. Technical effectiveness was 63.1 ± 9.1%, with 3 identified phases throughout the test (adaptation, maximum effectiveness, and steady decline). Low to moderate correlations were found between performance (final stage), physiological (VT1, VT2) and TE, and competitive performance (r = 0.35-0.61; p = 0.038-0.000). Technical effectiveness explained 37% of variability in competitive performance (r = 0.61; p = 0.001). Using TE combined with VT2 or predictability increased explaining approximately 55% (p < 0.05) of the variance in competitive performance. The present study showed the usefulness of a field test including physiological and performance elements in high-caliber tennis players, and VT2 values combined with TE were good predictors of tennis performance.
Central and peripheral fatigue have been explored during and after running or cycling exercises. However, the fatigue mechanisms associated with a short maximal cycling exercise (30 s Wingate test) have not been investigated. In this study, 10 volunteer subjects performed several isometric voluntary contractions using the leg muscle extensors before and after two bouts of cycling at 25% of maximal power output and two bouts of Wingate tests. Transcranial magnetic stimulation (TMS) and electrical motor nerve stimulation (NM) were applied at rest and during the voluntary contractions. Maximal voluntary contraction (MVC), voluntary activation (VA), twitch amplitude evoked by electrical nerve stimulation, M wave and motor potential evoked by TMS (MEP) were recorded. MVC, VA and twitch amplitude evoked at rest by NM decreased significantly after the first and second Wingate tests, indicating central and peripheral fatigue. MVC and VA, but not the twitch amplitude evoked by NM, recovered before the second Wingate test. These results suggest that the Wingate test results in a decrease in MVC associated with peripheral and central fatigue. While the peripheral fatigue is associated with an intramuscular impairment, the central fatigue seems to be the main reason for the Wingate test-induced impairment of MVC.
Thirteen patients with haemophilia A took part in this study voluntarily. They underwent an aquatic training programme over a 9-week period (27 sessions; three sessions per week; 1 h per session). Their motor performance was assessed by the following cardio-respiratory and mechanical variables before and after the training programme: oxygen uptake (VO(2), mL min(-1)), relative oxygen uptake (rel VO(2), mL min(-1).kg(-1)), carbon dioxide (CO(2), mL min(-1)), respiratory quotient (R), heart rate (bpm) and the distance covered in 12 min (the Cooper test, m). Nine patients successfully completed the intervention and measurement protocols without bleeding or other adverse events. After the proposed training programme, significant differences between the pre-test and post-test were observed. Patients' aerobic capacity increased considerably, and their oxygen uptake improved by 51.51% (P < 0.05), while their relative oxygen uptake went up by 37.73% (P < 0.05). Their mechanical capacity also increased considerably (14.68%, P < 0.01). Our results suggest that 27 specially designed aquatic training sessions for our patients with haemophilia A had a positive effect on their motor performance and considerably improved their aerobic and mechanical capacity without causing adverse effects.
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