Diurnal Variations in Upper and Lower Body Power in Adolescent Volleyball Players: Exploring Time-of-Day Effects on Performance.

Background/objectives: This study aims to investigate the daily variations in upper and lower body power performance in adolescent volleyball players.

Methods: The sample consisted of 50 young male volleyball players (14.12 ± 0.

Measuring handgrip strength in school children: inter-instrument reliability between Takei and Jamar.

The aim of this study was to determine inter-instrument reliability between Takei and Jamar dynamometers in school children. Fifty-six five grade participants aged eleven to twelve (n = 32 boys, n = 24 girls) performed handgrip strength test on two different occasions, with a 5-day gap between them, as test-retest. The Pearson correlation coefficient showed very large to almost perfect correlation between both devices (r = 0.

Adaptive changes in bodybuilders in conditions of different energy supply modes and intensity of training load regimes using machine and free weight exercises.

Background: The research was aimed at comparing the effect of using two types of training load different in intensity and energy supply. We studied the influence of the proposed load variations (machine and free weight exercises) on long-term adaptation of the body at the stage of specialized basic training in bodybuilding.

Methods: A total of 64 athletes aged 18-20 years were examined.

Criteria for assessing the adaptive changes in mixed martial arts (MMA) athletes of strike fighting style in different training load regimes.

Background: To study the peculiarities of changes in functional indicators and body composition parameters of mixed martial arts (MMA) athletes of strike fighting style and a number of biochemical blood indicators during two months of using different intensity training load regimes, and to determine the most informative criteria for assessing adaptive body changes in these training conditions.

Methods: We examined 40 MMA athletes (men) aged 20-22, who used mainly strike fighting style in their competitive activity, and divided them into 2 research groups (A and B), 20 athletes in each group. Group A athletes used medium intensity (  = 0.

Creatinine is a biochemical marker for assessing how untrained people adapt to fitness training loads.

Background: To study the peculiarities of changes in creatinine concentration in blood serum of untrained men during the prolonged usage of training loads different in volume and intensity, and to determine the value of this biochemical marker for the assessment of adaptive body changes during fitness training.

Methods: We examined 50 untrained men aged 18-20 years who had no contraindications for practicing fitness. Taking into account the aim of the research, we divided these people into two groups: group A and group B.