Can Heart Rate Variability Determine Recovery Following Distinct Strength Loadings? A Randomized Cross-Over Trial.

This study aimed to compare the acute effects of hypertrophic (HYP) and maximum strength (MAX) loadings on heart rate variability (HRV) and to compare possible loading-specific alterations with other markers of recovery. Ten young men with strength training experience performed two leg press loadings (HYP: five times 10 repetitions at 70% of one repetition maximum (1RM) with 2 minutes inter-set rest; MAX: 15 times one repetition at 100% of 1RM with 3 minutes inter-set rest) in a randomized order. The root mean square of successive differences statistically decreased after both protocols (HYP: 65.7 ± 26.6 ms to 23.9 ± 18.7 ms, p = 0.026; MAX: 77.7 ± 37.0 ms to 55.3 ± 22.3 ms, p = 0.049), while the frequency domains of HRV remained statistically unaltered. The low frequency (LF) band statistically increased at 48h post-MAX only (p = 0.033). Maximal isometric voluntary contraction (MVC) statistically decreased after HYP (p = 0.026) and returned to baseline after 24h of recovery. Creatine kinase (CK) statistically increased above baseline at 1h post-loadings (HYP p = 0.028; MAX p = 0.020), returning to baseline at 24h post. Our findings indicate no distinct associations between changes in HRV and MVC or CK.

Individual Motivations, Motivational Climate, Enjoyment, and Physical Competence Perceptions in Finnish Team Sport Athletes: A Prospective and Retrospective Study.

Despite the high rates of participation in sports clubs among Finnish youth, only a few reach elite levels. This study investigated a number of motivational factors, enjoyment, and perceived physical competence perceptions of Finnish youth athletes in their adolescence and then four years later to help understand determinants of elite level attainment. The sample consisted of 824 young athletes born in 1995, who were playing soccer, ice hockey, or basketball in the Finnish sports club system. As youths, participants completed measurements of the perceived task and ego climates, task and ego goal orientations, autonomous and controlled motivations, amotivation, sport enjoyment, and perceived physical competence. Retrospectively, the same participants completed measurements of task, ego, social relatedness, and autonomy supportive climates four years later. All variables were compared to self-reported elite status attainment. Additionally, we examined some demographic characteristics. Prospectively, the self-reported elite athletes (n = 79) reported significantly (p < 0.05) higher perceptions of a task climate, perceived physical competence, sport enjoyment, and autonomous motivation and a lower level of amotivation compared to nonelite athletes. The meaningfulness (Hedges' g) of the significant differences ranged from small to moderate. Retrospectively, elite athletes indicated significantly (p < 0.05) higher perception of a task climate and a social relatedness climate during their sporting career. Hedges' g ranged from moderate to large in meaningfulness. The findings highlighted the importance of focusing on the positive aspects surrounding elite athletes' perceptions to promote youth athletes' development, while not discounting the importance of physical size and talent.