Alpha-actinins are an ancient family of actin-binding proteins that play structural and regulatory roles in cytoskeletal organization. In skeletal muscle, α-actinin-3 protein is an important structural component of the Z disc, where it anchors actin thin filaments, helping to maintain the myofibrillar array. A common nonsense polymorphism in codon 577 of the ACTN3 gene (R577X) results in α-actinin-3 deficiency in XX homozygotes. Based on knowledge about the role of ACTN3 R557X polymorphism in skeletal muscle function, we postulated that the genetic polymorphism of ACTN3 could also improve sprint and power ability.We compared genotypic and allelic frequencies of the ACTN3 R557X polymorphism in two groups of men of the same Caucasian descent: 158 power-orientated athletes and 254 volunteers not involved in competitive sport.The genotype distribution in the group of power-oriented athletes showed significant differences (P=0.008) compared to controls. However, among the investigated subgroups of athletes, only the difference of ACTN3 R577X genotype between sprinters and controls reached statistical significance (P=0.041). The frequencies of the ACTN3 577X allele (30.69% vs. 40.35%; P=0.005) were significantly different in all athletes compared to controls.Our results support the hypothesis that the ACTN3 577XX allele may have some beneficial effect on sprint-power performance, because the ACTN3 XX genotype is significantly reduced in Polish power-oriented athletes compared to controls. This finding seems to be in agreement with previously reported case-control studies. However, ACTN3 polymorphism as a genetic marker for sport talent identification should be interpreted with great caution.

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We compared the effects of 16-week-training on rest metabolic rate, aerobic power, and body fat, and the post-exercise effects upon rest oxygen uptake and respiratory exchange ratio in overweight middle-aged females. Twenty nine overweight women (BMI 29.9 ± 1.2 kg*m−2) participated in training (3 days a week). The subjects were divided onto groups of aerobic (AT) and strength (ST) training. The results showed that the total body mass decrease and VO2 max increase did not differ in both groups. Decrease in waist circumference after 16 weeks was higher in the ST group. In the ST group fat-free mass increased during the first 8 weeks. Rest metabolic rate was increased significantly at 16th week compared to initial value in ST group only. Significant increase in post-exercise resting VO2 and respiratory exchange ratio at 12 and 36 h was observed after the strength training session only. Increase in rest metabolic rate and post-exercise rest energy expenditure occurred after strength training but not after aerobic training despite the similar increase in aerobic power. The effect of 8–16 weeks of strength training on body mass decrease was higher in comparison to aerobic training.

Thus far, genetic studies of the renin-angiotensin system (RAS) with respect to athletic performance or athlete status have mainly focused on the angiotensin-converting enzyme gene and its insertion/deletion polymorphism. The aim of this study was to investigate the functional rs699 (M235T) polymorphism in angiotensinogen (AGT), the second most important gene of the RAS, for association with athletic status and level of performance. The study included 123 endurance athletes and 100 power-oriented athletes, who were classified as elite or sub-elite according to competitive achievements at the international level, and 354 unrelated sedentary control subjects. The M235T genotype and allele distributions differed significantly between power and endurance athletes (p < 0.0001 and p < 0.0002, genotypes and alleles, respectively) and between power athletes and control subjects (p < 0.0001 and p < 0.0002, genotypes and alleles, respectively). The frequency of the CC genotype in the power athlete group was 2.2 times higher and 3.1 times higher than in the control and endurance groups, respectively. No difference was found in M235T allele distribution between elite and sub-elite athletes, either in power- or endurance-oriented athletes. We conclude that the CC genotype of the M235T polymorphism is overrepresented in Polish power athletes, suggesting that the AGT M235T variant is associated with power athletes' status.

Background The main aim of the study is to define the profile of positive health and survival abilities in women differing as to physical activity. Thus formulated study aim was connected with answering the following question: do young women, undergraduate students at the Faculty of Tourism and Recreation, who declare daily physical activity substantially differ from their peers declaring occasional activity in the sense of positive health in all its aspects and in self-assessment of their survival abilities? Material/Methods: The profile of women's positive health and survival abilities was defined on the basis of Kalina's original methodology (2012) taking into account four aspects of indices: the somatic (A), mental (B), social (C) and reflecting survival abilities (D) ones. The arithmetic mean calculated for indices A to D represents the most general index of the Sense of Positive Health and Survival Abilities (SPHSA). The studied group was composed of female students from the Faculty of Tourism and Recreation completing their education at the undergraduate level (6 th semester). 24 students declared daily physical activity, and 34 students the occasional one. The subjects' age was within the range of 20-23 years (21.24±0.99). Results: Women declaring daily physical activity surpass their occasionally active peers in the SPHSA index-3.740 and 3.427, respectively (p<0.01). The highest value of indices in both groups was noted in social health (4.08 and 3.95), while the lowest one in the survival ability (3.5 and 3.165). Students who are active every day have statistically higher values than their occasionally active peers in the following indices: aerobic capacity (p<0.01), flexibility (p<0.001), muscular power (p<0.001), lesser aggressiveness (p<0.05), anxiety (p<0.001), skill of safe falling (p<0.05), and the ability to act precisely before and after physical activity (p<0.05). Conclusions: Physical activity constitutes an important factor modifying the sense of positive health and the survival ability. The structure of the SPHSA profile was similar in both groups. The differences regarded the intensity of those aspects which undergo the greatest changes under the influence of physical activity: somatic and mental health.