PURPOSE: The main goal of this study was to assess the acute effects of 3 and 6 mg of caffeine intake per kg of body mass (b.m.) on maximal strength and strength-endurance in women habituated to caffeine. METHODS: Twenty-one healthy resistance-trained female students (23.0 ± 0.9 years, body mass: 59.0 ± 6.6 kg), with a daily caffeine intake of 5.8 ± 2.6 mg/kg/b.m. participated in a randomized, crossover, double-blind design. Each participant performed three experimental sessions after ingesting either a placebo (PLAC) or 3 mg/kg/b.m. (CAF-3) and 6 mg/kg/b.m. (CAF-6) of caffeine. In each experimental session, the participants underwent a 1RM test and a strength-endurance test at 50 %1RM in the bench press exercise. Maximal load was measured in the 1RM test and the time under tension, number of preformed repetitions, power output and bar velocity were registered in the strength-endurance test. RESULTS: The one-way ANOVA showed a main effect of caffeine on 1RM bench press performance (F = 14.74; p < 0.01). In comparison to the PLAC (40.48 ± 9.21 kg), CAF-3 (41.68 ± 8.98 kg; p = 0.01) and CAF-6 (42.98 ± 8.79 kg; p < 0.01) increased 1RM bench press test results. There was also a significant increase in 1RM for CAF-6 when compared to CAF-3 (p < 0.01). There was a main effect of caffeine on time under tension during the strength-endurance test (F = 13.09; p < 0.01). In comparison to the PLAC (53.52 ± 11.44 s), CAF-6 (61.76 ± 15.39 s; p < 0.01) significantly increased the time under tension during the maximal strength-endurance test. CONCLUSION: An acute dose of 3-to-6 mg/kg/b.m. of caffeine improves maximum strength. However, these doses of caffeine had minimal ergogenic effect on strength-endurance performance in women habituated to caffeine.

• MeSH
• aplikace orální MeSH
• chování při pití MeSH
• dvojitá slepá metoda MeSH
• fyzická vytrvalost účinky léků   MeSH
• klinické křížové studie MeSH
• kofein aplikace a dávkování   MeSH
• látky zvyšující výkon aplikace a dávkování   MeSH
• lidé MeSH
• mladý dospělý MeSH
• svalová síla účinky léků   MeSH
• Check Tag
• lidé MeSH
• mladý dospělý MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• randomizované kontrolované studie MeSH

BACKGROUND: Although the scientific literature regarding sports genomics has grown during the last decade, some genes, such as peroxisome proliferator activated receptors (PPARs), have not been fully described in terms of their role in achieving extraordinary sports performance. Therefore, the purpose of this systematic review was to determine which elite sports performance constraints are positively influenced by PPARs and their coactivators. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used, with a combination of PPAR and sports keywords. RESULTS: In total, 27 studies that referred to PPARs in elite athletes were included, where the Ala allele in PPARG rs1801282 was associated with strength and power elite athlete status in comparison to subelite athlete status. The C allele in PPARA rs4253778 was associated with soccer, and the G allele PPARA rs4253778 was associated with endurance elite athlete status. Other elite status endurance alleles were the Gly allele in PPARGC1A rs8192678 and the C allele PPARD rs2016520. CONCLUSIONS: PPARs can be used for estimating the potential to achieve elite status in human physical performance in strength and power, team, and aerobic sports disciplines. Carrying specific PPAR alleles can provide a partial benefit to achieving elite sports status, but does not preclude achieving elite status if they are absent.

• MeSH
• alely MeSH
• frekvence genu MeSH
• fyzická vytrvalost MeSH
• genetická variace MeSH
• lidé MeSH
• PPAR alfa genetika   MeSH
• PPAR gama genetika   MeSH
• PPARGC1A genetika   MeSH
• sportovci MeSH
• sportovní výkon MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

The combined effect of diet and strength training (ST) on blood pressure (BP) seems to be very important for the treatment of prehypertension and hypertension (HT). Therefore, the aim of this study was to determine whether ST alone or combined with nutrition or supplementation has an impact on the arterial pressure reduction in normotensive and hypertensive populations. A systematic computerized literature search was performed according to the PRISMA guidelines using PubMed, Scopus and Google Scholar; only English language studies published from 1999 until 2018 were included. This systematic search identified the results of 303 individuals from nine studies. The ST program alone had a similar effectiveness as the nutrition program (NP) alone; however, their combination did not result in increased effectiveness in terms of a high BP reduction. The consumption of L-citrulline had a similar effect as ST on lowering BP; on the other hand, caffeine led to an increase in BP during the ST session. Our data suggest that a combination of ST 2-3 times a week at moderate intensity and a NP seems to be equally effective in terms of lowering BP (systolic and diastolic) as ST and NP alone.

• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

BACKGROUND: PPARα is a transcriptional factor that controls the expression of genes involved in fatty acid metabolism, including fatty acid transport, uptake by the cells, intracellular binding, and activation, as well as catabolism (particularly mitochondrial fatty acid oxidation) or storage. PPARA gene polymorphisms may be crucial for maintaining lipid homeostasis and in this way, being responsible for developing specific training-induced physiological reactions. Therefore, we have decided to check if post-training changes of body mass measurements as well as chosen biochemical parameters are modulation by the PPARA genotypes. METHODS: We have examined the genotype and alleles' frequencies (described in PPARA rs1800206 and rs4253778 polymorphic sites) in 168 female participants engaged in a 12-week training program. Body composition and biochemical parameters were measured before and after the completion of a whole training program. RESULTS: Statistical analyses revealed that PPARA intron 7 rs4253778 CC genotype modulate training response by increasing low-density lipoproteins (LDL) and glucose concentration, while PPARA Leu162Val rs1800206 CG genotype polymorphism interacts in a decrease in high-density lipoproteins (HDL) concentration. CONCLUSIONS: Carriers of PPARA intron 7 rs4253778 CC genotype and Leu162Val rs1800206 CG genotype might have potential negative training-induced cholesterol and glucose changes after aerobic exercise.

• Publikační typ
• časopisecké články MeSH

The nutrition of soccer players is an important topic and its knowledge may help to increase the quality of this popular game and prevent possible health problems and injuries in players. This meta-analysis aims to estimate the current dietary trends of three basic macronutrients in junior and senior soccer players during the first two decades of the 21st century. We analyzed data from 647 junior players (mean age 10.0-19.3) from 27 groups, and 277 senior (mean age 20.7-27.1) players from 8 groups from altogether 21 papers in this meta-analysis. Weighted averages were calculated for each macronutrients. Protein intake is higher than recommended in both juniors, 1.9 95% confidence interval (CI) 1.8-2.0 g/kg/day, and seniors 1.8 95% CI 1.6-2.0 g/kg/day. However, carbohydrate intake is still below the recommended values in both groups (5.7 95% CI 5.5-5.9 g/kg/day in junior and 4.7 95% CI 4.3-5.0 g/kg/day in senior players). The proportion of fat as total energy intake is in concordance with the recommendations (31.5 95% CI 32.0-35.9% in junior and 33.1 95% CI 29.9-36.2% in senior players). In particular, due to possible health complications, the small carbohydrate intake should be alarming for coaches, nutritional experts, and parents.

• MeSH
• dieta * MeSH
• dietní proteiny aplikace a dávkování   MeSH
• dietní sacharidy aplikace a dávkování   MeSH
• dietní tuky aplikace a dávkování   MeSH
• dítě MeSH
• dospělí MeSH
• energetický příjem MeSH
• fotbal * MeSH
• fyziologie sportovní výživy MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• nutriční nároky * MeSH
• sportovci MeSH
• stravovací zvyklosti * MeSH
• výživová politika MeSH
• živiny MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• Publikační typ
• časopisecké články MeSH
• metaanalýza MeSH