The purpose of this study was to determine whether delaying bedtime or advancing rising time by 4 h affects anaerobic performance of individuals the following day in the morning and afternoon. Eleven subjects participated in the study, during which we measured the maximal, peak, and mean powers (i.e., P(max) [force-velocity test], P(peak), and P(mean) [Wingate test], respectively). Measurements were performed twice daily, at 07:00 and 18:00 h, following a reference normal sleep night (RN), a partial sleep deprivation timed at the beginning of the night (SDB), and a partial sleep deprivation timed at the end of the night (SDE), and oral temperature was measured every 4 h. Each of the three experimental conditions was separated by a one-week period. Our results showed a circadian rhythm in oral temperature, and analysis of variance revealed a significant sleep x test-time effect on peak power (P(peak)), mean power (P(mean)), and maximal power (P(max)). These variables improved significantly from the morning to the afternoon for all three experimental conditions. Whereas the morning-afternoon improvement in the measures was similar after the RN and SDB conditions, it was smaller following the SDE condition. There was no significant difference in the effect of the two sleep-deprivation conditions on anaerobic performances at 07:00 and at 18:00 h under the SDB condition in comparison with the post-reference night. However, the performance variables were significantly lower at 18:00 h after the SDE condition. In conclusion, a 4 h partial sleep deprivation at the end of the night appears to be more disturbing than partial sleep deprivation at the beginning of the night.

Verbal encouragement (VE) can be used by physical education (PE) practitioners for boosting motivation during exercise engagement. The purpose of this study was to investigate the effects of VE on psychophysiological aspects and physical performance in a PE context. Twenty secondary school male students (age: 17.68 ± 0.51 yrs; height: 175.7 ± 6.2 cm; body mass: 67.3 ± 5.1 kg, %fat: 11.9 ± 3.1%; PE experience: 10.9 ± 1.0 yrs) completed, in a randomized order, two test sessions that comprised a soccer dribbling circuit exercise (the Hoff circuit) either with VE (CVE) or without VE (CNVE), with one-week apart between the tests. Heart rate (HR) responses were recorded throughout the circuit exercise sessions. Additionally, the profile of mood-state (POMS) was assessed pre and post the circuit exercises. Furthermore, rating of perceived exertion (RPE), traveled distance, and physical activity enjoyment (PACES) were assessed after the testing sessions. Furthermore, the CVE trial resulted in higher covered distance, %HRmax, RPE, PACES score, (Cohen’s coefficient d = 1.08, d = 1.86, d = 1.37, respectively; all, p < 0.01). The CNVE trial also showed lower vigor and higher total mood disturbance (TMD) (d = 0.67, d = 0.87, respectively, p < 0.05) and was associated with higher tension and fatigue, compared to the CVE trial (d = 0.77, d = 1.23, respectively, p < 0.01). The findings suggest that PE teachers may use verbal cues during soccer dribbling circuits for improving physical and psychophysiological responses within secondary school students.

The effects of three corrections strategies of errors on the snatch technique in 10-12-year-old children: A randomized controlled trial. J Strength Cond Res 37(6): 1218-1224, 2023-Sports movement correction is one of the major problems for motor control and learning. Therefore, the purpose of the present study was to determine which of the 3 strategies, i.e., the self-observation method with direct instructions (SO-DI), self-observation alone (SO), or the direct instruction (DI), would be useful for correcting errors during the snatch technique. Forty-eight children with 2 months of experience were randomly assigned to one of 4 training conditions: SO-DI, SO, DI, or control. In this study, the experience lasted 15 sessions. Subjects completed the test sessions before (T 0 ) and after (T 1 ) 12 training sessions and a retention test session after 2 weeks (T 2 ). The Kinovea version 0.8.15 software was used to measure the kinematic parameters of weightlifting performance. After the training intervention, the data showed that the SO-DI group registered a greater improvement in all kinematic parameters compared with the SO, DI, and control groups, and this benefit was present 2 weeks later in the retention test (e.g., the horizontal displacement of the bar in the first pull with respect to the starting position [T1 vs. T0: +32.57 6 6.69%, d 5 1.87, p , 0.001; T2 vs. T0: 25.07 6 11.55%, d 5 1.32, p , 0.001] and the horizontal displacement of the bar between the receiving position and the reference line [T1 vs. T0: 24.34 6 29%, d 5 1.17, p , 0.01; T2 vs. T0: 25.53 6 30.4%, d 5 0.99, p , 0.01]). The results of the present study could have practical implications for physical education teachers because, even if practice is required to improve the technique, the effectiveness of the learning process is essential to enhance learner self-efficacy and motivation.

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Our aim in this study was to examine, via technical performance analysis and speed of execution, whether information processing and technical knowledge help explain learning benefits of self-controlled video feedback in children’s weightlifting performance. We randomized 24 children (aged 10 to 12 years) into self-controlled (SC) and yoked (YK) feedback groups. Learners underwent test sessions one week before (pre-test) and one day after (post-test) six weightlifting training sessions. During each test session, we recorded kinematic parameters of snatch performance using Kinovea version 0.8.15 software. After the learning sessions, the SC group improved on most kinematic parameters (e.g., the horizontal displacement of the bar between the first and the second pulls [ MDXV = 25.42%, SD = 18.96, p = 0.003) and the maximum height reached by the bar ( MHMV = 5.51%, SD = 7.71, p < 0.05)], while the YK group improved only on the DxV ( MDXV = 19.08%, SD = 24.68, p < 0.05). In addition, the SC group showed a more advanced phase of cognitive processing compared to the YK group, and the SC group showed a superior improvement in their technical knowledge level ( p < 0.001) compared to the YK group ( p < 0.05). Thus, key elements to correcting motor errors in children’s weightlifting through self-controlled feedback were improvements in information processing and technical knowledge.