Effects of a Tapering Period on Physical Condition in Soccer Players.

Beltran-Valls, MR, Camarero-López, G, Beltran-Garrido, JV, and Cecilia-Gallego, P. Effects of a tapering period on physical condition in soccer players. J Strength Cond Res 34(4): 1086-1092, 2020-The aim of this research was to analyze the effects of a 2-week step tapering period on lower-limb muscle power, change of direction (COD) and acceleration capacities, and on the stress-recovery state in an amateur soccer team. Twenty-two male players were included in the study. After a 6-week progressive training, the sample was divided into experimental group (EG) (n = 11), which did a 2-week period of taper in which training volume was 50% reduced (intensity was kept high) and control group (CG) (n = 11), which kept on with the training. Muscle power (countermovement jump test), acceleration (10-m sprint test), COD (Illinois test), and stress and recovery perceptions (RESTQ questionnaire) were evaluated before training, at the end of it (pretapering, PRE-TP) and after the tapering period (posttapering, POST-TP). After the taper, the EG in comparison with the CG showed significantly improved power (1,029.71 ± 108.51 W·kg vs. 1,084.21 ± 110.87 W·kg; p ≤ 0.01), acceleration (1.72 ± 0.09 seconds vs. 1.67 ± 0.07 seconds; p ≤ 0.05), and lower stress levels (1.9 ± 0.5 vs. 1.6 ± 0.5; p ≤ 0.01) (PRE-TP vs. POST-TP, respectively). Change of direction did not show significant changes. In conclusion, a 2-week step tapering program was found to be an effective periodization strategy to increase muscle power and acceleration, and to reduce stress perception in soccer amateur players.

Contralateral Effects After Unilateral Strength Training: A Meta-Analysis Comparing Training Loads.

There is solid evidence on the cross-training phenomenon, but the training load required to achieve it has yet to be established. The aim of this meta-analysis was to deduce which unilateral strength training load (duration, frequency, intensity, rest and type) would enable the biggest strength increases to be obtained in the inactive contralateral limb. The examined studies were limited to those written in the English language within the Web of Science, PubMed and SPORTDiscus databases. Ten of the 43 eligible studies were included, covering a total of 409 participants. The studies included in the meta-analysis showed a low risk of bias and had an estimated pooled effect size of 0.56 (95% CI from 0.34 to 0.78). Greater effect sizes were observed in lengthy protocols involving fast eccentric exercises using designs of 3 sets of 10 repetitions and a 2-minute rest time. Effect size did not relate to absolute volume, relative intensity, absolute duration and speed of execution. In conclusion, to optimize contralateral strength improvements, cross-training sessions should involve fast eccentric sets with moderate volumes and rest intervals.

Sleep quality is mediated by physical activity level in adolescents.

BACKGROUND: Sleep is essential for the adolescent's health and well-being. Despite existing evidence of the positive relationship between physical activity and quality of sleep, some other factors could mediate this association. The purpose of the present study was to clarify the interaction between the level of physical activity and sleep in adolescents depending on their gender. METHODS: A total of 12,459 subjects 11 to 19 years old (5073 male and 5016 female) reported data regarding their quality of sleep and their level of physical activity. RESULTS: Better quality of sleep was reported by males regardless of the level of physical activity (d=0.25, P<0.001). Better quality of sleep was reported by active subjects (P<0.05), and it improved in both sexes as the level of physical activity was higher (P<0.001). CONCLUSIONS: Male adolescents have better sleep quality than females regardless of their competitive level. The higher the adolescents' physical activity level the higher the quality of sleep.

Validity and Reliability of the V-Cut Dribbling Test in Young Basketball Players.

PURPOSE: Change of direction while dribbling appears to be of interest for on-court performance in basketball. The study aim was to assess the validity and reliability of the V-cut dribbling test (VcutBk) in young basketball players. METHODS: Ninety-two young basketball players from 8 to 21 years old (74% male) were classified in relation to peak height velocity (PHV) offset. To examine validity and test-retest reliability, VcutBk was performed in 2 identical sessions separated by 1 week. Participants also performed the V-cut test and linear sprint test with and without dribbling to analyze correlations between tests in different somatic maturity stages. RESULTS: The relationships of the VcutBk with the other tests and skill-time-related deficits were interpreted from large (r > .51) to very large (r > .71). The comparisons between pre-PHV and post-PHV groups of basketball players showed significant and large effect in the VcutBk (d = 2.04; mean difference = 2.59; 95% CI, 1.86 to 3.32). Also, significant main effects when comparing PHV groups were reported in all skill-time-related deficits (P < .001, ηp2=.13-.28, moderate to large effect size). Test-retest reliability and signal-to-noise ratio analysis did not show substantial between-trials differences in VcutBk. Reliability scores showed high intraclass correlation coefficient (.95) and low coefficient of variation (0.23%). CONCLUSIONS: The VcutBk seems to be a valid and reliable test to assess change of direction while dribbling. VcutBk performance and skill-time-related deficits seem to be sensitive to somatic maturity. Basketball coaches should consider the VcutBk to assess young basketball players.