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  • Author: Tarak Driss x
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Hamdi Jaafar, Majdi Rouis, Elvis Attiogbé, Henry Vandewalle and Tarak Driss

Purpose:

To verify the hypothesis that the peak power (PP) of a Wingate test (WT) is an underestimation of maximal power (Pmax) computed from the force–velocity test (FVT), to examine possible fatigue effect on Pmax, and to investigate the effect of load on mean power (MP) and fatigue index (FI) during a WT in trained and recreational men.

Methods:

Ten recreational (22.9 ± 1.7 y, 1.81 ± 0.06 m, 73.3 ± 10.4 kg) and 10 highly trained subjects (22.7 ± 1.4 y, 1.85 ± 0.05 m, 78.9 ± 6.6 kg) performed 2 WTs with 2 loads (8.7% and 11% of body mass [BM]) and an FVT on the same cycle ergometer, in randomized order.

Results:

Optimal load was equal to 10% BM in recreational participants. Given the quadratic relationship between load and power, the underestimation of Pmax was lower than 10% for the average values of trained and recreational participants with both loads. However, PP with a load equal to 8.7% BM was a large underestimation (~30%) of Pmax in the most powerful individuals. In addition, PP was not greater than Pmax of FVT for the same load. FI was independent of the load only if it was expressed relative to PP. The optimal load for MP during WT was close to the optimal load for PP.

Conclusions:

The optimal load for WT performance should be approximately equal to 10% BM in recreational subjects. In powerful subjects, the FVT appears to be more appropriate in assessing maximal power, and loads higher than 11% BM should be verified for the WT.

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Achraf Ammar, Stephen J. Bailey, Omar Hammouda, Khaled Trabelsi, Nabil Merzigui, Kais El Abed, Tarak Driss, Anita Hökelmann, Fatma Ayadi, Hamdi Chtourou, Adnen Gharbi and Mouna Turki

Purpose: The effect of playing surface on physical performance during a repeated-sprint ability (RSA) test and the mechanisms for any potential playing-surface-dependent effects on RSA performance are equivocal. The purpose of this study was to investigate the effect of natural grass (NG) and artificial turf (AT) on physical performance, ratings of perceived exertion, feeling scale, and blood biomarkers related to anaerobic contribution (blood lactate [Lac]), muscle damage (creatine kinase and lactate dehydrogenase), inflammation (C-reactive protein), and immune function (neutrophils [NEU], lymphocytes [LYM], and monocytes) in response to an RSA test. Methods: A total of 9 male professional football players from the same regional team completed 2 sessions of RSA testing (6 × 30 s interspersed with a 35-s recovery) on NG and AT in a randomized order. During the RSA test, total (sum of distances) and peak (highest distance covered in a single repetition) distance covered were determined using a measuring tape, and the decrement in sprinting performance from the first to the last repetition was calculated. Before and after the RSA test, ratings of perceived exertion, feeling scale, and Lac, creatine kinase, lactate dehydrogenase, C-reactive protein, NEU, LYM, and monocytes were recorded in both NG and AT conditions. Results: Although physical performance declined during the RSA blocks on both surfaces (P = .001), the distance covered declined more on NG (15%) than on AT (11%; P = .04; effect size [ES] = −0.34; 95% confidence interval [CI], −1.21 to 0.56) with a higher total distance covered (+6% [2%]) on AT (P = .018; ES = 1.15; 95% CI, 0.16 to 2.04). In addition, lower ratings of perceived exertion (P = .04; ES = −0.49; 95% CI, −1.36 to 0.42), Lac, NEU, and LYM (P = .03; ES = −0.80; 95% CI, −1.67 to 0.14; ES = −0.16; 95% CI, −1.03 to 0.72; and ES = −0.94; 95% CI, −1.82 to 0.02, respectively) and more positive feelings (P = .02; ES = 0.81; 95% CI, −0.13 to 1.69) were observed after the RSA test performed on AT than on NG. No differences were observed in the remaining physical and blood markers. Conclusion: These findings suggest that RSA performance is enhanced on AT compared with NG. This effect was accompanied by lower fatigue perception and Lac, NEU, and LYM and a more pleasurable feeling. These observations might have implications for physical performance in intermittent team-sport athletes who train and compete on different playing surfaces.