Effects of Co-Ingestion of ß-Hydroxy-ß-Methylbutyrate and L-Arginine α-Ketoglutarate on Jump Performance in Young Track and Field Athletes.

The aim of the study was to determine the effect of simultaneous supplementation of ß-hydroxy-ß-methylbutyrate and L-Arginine α-ketoglutarate on lower limb power and muscle damage in medium distance runners aged 15.3 (±0.9) years old. METHODS: The study group consisted of 40 volunteers aged 14-17 years practicing medium distance running for at least two years. The study lasted 12 days and followed a randomized, double-blind, placebo-controlled, parallel design. All subjects attended a familiarization session on day 0 before the test. The subjects were randomly divided into two groups: supplements and placebo group. The same training cycle protocol was used in both groups during the 12-day training period. Morning warm-up involved 10 min jogging at 60-75% of maximal heart rate and countermovement jump height measurement. Main training units were carried out for both groups with the same volume. Training load assessment (the daily session Rating of Perceived Exertion (s-RPE) method) method takes into consideration the intensity and the duration of the training session to calculate the "training load" (TL). RESULTS: At the end of the training cycle, a significant (p = 0.002) decrease in the countermovement jump (CMJ) height was found in the placebo group when compared to the baseline. In the supplement group, there was no decrease in the countermovement jump height. Creatine kinase and lactate dehydrogenase concentration increased during the training days similarly in both groups and decreased on rest days. There were no differences between groups in enzymes concentration. The research results indicate that the supplement combination used in the supplements group prevented a reduction in the CMJ values. In contrast to the supplements group, in the placebo group, the CMJ changes were statistically significant: a noticeable (p = 0.002) decrease in CMJ was noted between the baseline measurement and the 6th measurement. The well-being of the subjects from both groups changed significantly during the training period, and the intergroup differences in the mood level were similar and not statistically significant. CONCLUSIONS: The results of this study indicate that the daily co-supplementation with calcium salt of ß-hydroxy-ß-methylbutyrate (7.5 g) and L-Arginine α-ketoglutarate (10 g) during training might help to prevent decline in jump performance. No influence on muscle damage markers or mood was shown.

Effects of Pre-Workout Multi-Ingredient Supplement on Anaerobic Performance: Randomized Double-Blind Crossover Study.

BACKGROUND: The purpose of this research was to investigate the acute effects of a pre-workout supplement on anaerobic performance in resistance-trained men. METHODS: Twenty-three men underwent three randomized, double-blind testing sessions separated by a seven-day break. The participants performed three tests: isokinetic strength, three repetition maximum (3-RM) strength and Wingate. Statistical analysis was conducted in R environment. Linear mixed models were estimated via R package lme4. RESULTS: Mean T@0.2 s was significantly greater in supplemented condition for right and left knee flexors (PL: 103.2 ± 37.6 Nm; supplemented condition: 131.8 ± 29.3 Nm (p = 0.001)), and PL: 103.7 ± 39.3; supplemented condition: 129.4 ± 28.4 (p = 0.001)). T@0.2 s for right and left knee extensors (PL: 202.6 ± 58.6 Nm; supplemented condition: 237.2 ± 54.7 Nm (p = 0.001); PL: 203.3 ± 63.2 Nm, supplemented condition: 229.8 ± 50.8 Nm (p = 0.002)). Significant difference was in mean anaerobic power between supplemented and PL condition for right and left knee flexors (p = 0.002, p = 0.005) and for right and left knee extensors (p = 0.001 and p = 0.002). TTP was significantly shorter in supplemented condition for both sides knee flexors (p = 0.002). There was a significant difference for mean power in the Wingate test (placebo: 8.5 ± 0.6 W/kg; supplemented condition: 8.7 ± 0.5 W/kg (p = 0.038)). Mean 3-RM was significantly greater in supplemented condition (p = 0.001). CONCLUSIONS: The supplement significantly improves upper and lower body strength and power output in resistance-trained men.

Concentration of 25(OH)D3 and calcium and phosphorus metabolism in patients suffering from relapsing-remitting multiple sclerosis. A pilot study.

BACKGROUND AND PURPOSE: The aim of this study was to evaluate the concentration of 25(OH)D3 and the indices of calcium and phosphorus metabolism at different times of relapsing-remitting multiple sclerosis (MS). The relationships between the concentrations of 25(OH)D3 and the indices of calcium-phosphate metabolism were determined, depending on the duration of disease and vitamin and unsaturated fatty acids supplementation. MATERIAL AND METHODS: Thirty patients (15 at the early stage and 15 at the advanced stage of MS) were enrolled. Each patient underwent neurological examination; neurological motor disability was defined according to the Expanded Disability Status Scale (EDSS). The results were compared to the values obtained in the control group (15 individuals) selected according to the age of subjects, their residence, ethnicity and gender. RESULTS: Significantly lower serum concentrations of 25(OH)D3 in MS patients compared to the control group were found. MS patients at the advanced stage of the disease (duration of 5-6 years) had lower 25(OH)D3 concentrations than patients at the early stage of MS. Among patients in an advanced stage of MS, significantly lower levels of 25(OH)D3 were found in women compared to men with a similar level of physical disability. CONCLUSIONS: Lower serum concentrations of 25(OH)D3 in MS patients compared to the control group were found. The lowest concentrations of 25(OH)D3 were found in female patients aged 20-40 and in patients with a longer disease duration without substantial impairment of calcium-phosphate metabolism.