Search

Background: The purpose of this study was to examine the acute effect of a caffeine-based multi-ingredient supplement (MS) on the reactive agility and jump performance in recreational handball male players. Methods: A randomized, double-blind, crossover study involved twenty-four male handball players. All participants were tested under three conditions: placebo, caffeine, or MS ingestion 45 minutes before exercise tests. Participants performed a reactive agility test (Y-test: 1-1-2 test) and countermovement jump (CMJ).Results: None of the supplements improved countermovement jump height. The time needed to complete the 1-1-2 test was significantly shorter in MS condition compared to placebo. The differences in agility between PL vs. caffeine and MS vs. caffeine conditions were not statistically significant.Conclusions: The results of this study indicate that the caffeine-based multi-ingredient performance was effective in improvement in reactive agility but not in jump height in recreational handball male players. A similar effect was not observed with caffeine ingestion alone. Further comparative studies (MS ingestion vs. only caffeine ingestion) and MS with different compositions are needed.

BackgroundThe purpose of this investigation was to examine the acute effects of a commercially available multi-ingredient performance supplement (MIPS) in comparison to caffeine, on reactive agility and jump height, in recreationally-trained handball male players. MethodsThe study followed a randomized double-blind, crossover design. Twenty-four individuals were treated with placebo, caffeine or multi-ingredient performance supplement (MIPS). Dosage of caffeine in caffeine supplement and MIPS contain the same amounts of caffeine for each subject (5 mg/kg) . All subjects attended a familiarization session 1 week before testing. Participants underwent reactive agility test (Y-test: 1-1-2 test) on three separate days with 72 h apart between test days. Just after accomplishing of each repetition of reactive agility tests participants were asked to perform countermovement jump (CMJ; 2 repetitions separated by one minute break) to establish the average height of jump, that is directly related to lower body power. To assess the significance of differences between the groups studied, Friedmann ANOVA test was used, the chi-square value (χ2) calculated and the p value of statistical significance estimated. ResultsThe research indicated significant inter-group differences in 1-1-2 agility test (p=0.04). The time was significantly shorter for MIPS supplement group in comparison to placebo (-3.4%; p=0.02) and to caffeine (-2.8%; p=0.004) group. Significant improvements (p

Background: The aim of the study was to determine the effect of simultaneous supplementation of β-hydroxy-β-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 (men and women) aged 14-17 (juniors and younger juniors) who have been practicing medium distance running for at least two years. The study followed a randomised, double-blind, placebo-controlled design. All subjects attended a familiarisation session on day 0 before the test commenced. The subjects were randomly divided into two groups: supplements group and placebo group. A similar training cycle protocol was used in both groups. Daily sRPE values, countermovement jump measurement as well as blood creatine kinase and lactate dehydrogenase were measured during 12-day training period. Results: After 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 measurement. In the supplements group, there was no decrease in the countermovement jump value, which was close to the baseline level after the end of the training cycle (p>0.05). During the 12-day training period, statistically significant changes in creatine kinase and lactate dehydrogenase levels were recorded between the supplements and placebo groups; its concentration increased during the training weeks similarly, and decreased on rest. All the changes were at a comparable level in both groups. The research results indicate that the supplement combination used in the supplements group prevented a reduction in the CMJ values. In contrast to 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 β-hydroxy-β-methylbutyrate (6 g) and L-arginine α-ketoglutarate (8 g) during the 12-day intensive training camp may prevent deterioration of lower limb muscle power measured by the CMJ test in the well-trained youth track and field athletes. Keywords: training camp supplementation, medium distance runners, β-hydroxy-β-methylbutyrate, HMB, L-arginine α-ketoglutarate, AAKG, countermovement jump, CK- creatine kinase, LDH – lactate dehydrogenase.

In recent years, commensal bacteria colonizing the human body have been recognized as important determinants of health and multiple pathologic conditions. Among the most extensively studied commensal bacteria are the gut microbiota, which perform a plethora of functions, including the synthesis of bioactive products, metabolism of dietary compounds, and immunomodulation, both through attenuation and immunostimulation. An imbalance in the microbiota population, i.e., dysbiosis, has been linked to many human pathologies, including various cancer types and neurodegenerative diseases. Targeting gut microbiota and microbiome–host interactions resulting from probiotics, prebiotics, and postbiotics is a growing opportunity for the effective treatment of various diseases. As more research is being conducted, the microbiome field is shifting from simple descriptive analysis of commensal compositions to more molecular, cellular, and functional studies. Insight into these mechanisms is of paramount importance for understanding and modulating the effects that microbiota, probiotics, and their derivatives exert on host health.

Beta-hydroxy-beta-methylbutyrate (HMB) has been used extensively as a dietary supplement for athletes and physically active people. HMB is a leucine metabolite, which is one of three branched chain amino acids. HMB plays multiple roles in the human body of which most important ones include protein metabolism, insulin activity and skeletal muscle hypertrophy. The ergogenic effects of HMB supplementation are related to the enhancement of sarcolemma integrity, inhibition of protein degradation (ubiquitin pathway), decreased cell apoptosis, increased protein synthesis (mTOR pathway), stimulation of the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis and enhancement of muscle stem cells proliferation and differentiation. HMB supplementation has been carried out with various groups of athletes. In endurance and martial arts athletes, HMB supplementation revealed positive effects on specific aerobic capacity variables. Positive results were also disclosed in resistance trained athletes, where changes in strength, body fat and muscle mass as well as anaerobic performance and power output were observed. The purpose of this review was to present the main mechanisms of HMB action, especially related to muscle protein synthesis and degradation, and ergogenic effects on different types of sports and physical activities.