The purpose of this study was to elucidate the effects of cycling training with blood flow restriction on muscle function, aerobic capacity, and arterial stiffness. Twelve healthy men were randomly divided into two training groups; those training with blood flow restriction (BFR group, n=7) and those training without restriction as the control (n=5). Both groups trained 3 days a week for 4 weeks, with each training period lasting 30 minutes. The exercise intensity was set as 45% of oxygen uptake reserve for the first two weeks and 50% for the last two weeks. For the BFR group, blood flow restriction was performed every 5 minutes for periods of 5 minutes (totaling 15 minutes) by applying cuffs to both upper thighs with pressure set at 160mmHg, which subsequently increased by 10 mmHg every week. This study showed that peak oxygen uptake significantly increased after training in both groups. On the other hand, maximal isometric knee extension strength significantly increased in post-training only for the BFR group. Cardio-ankle vascular index, which is an indicator of arterial stiffness, was not significantly changed for either group after training, regardless of the BFR group showing significant enhancement in blood pressure response to exercise with blood flow restriction. These results suggest that 4 weeks of moderate-intensity cycling training with intermitted blood flow restriction could improve not only aerobic capacity but muscle function as well, all without a significant increase in arterial stiffness.

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BACKGROUND Although weight loss behavior in high school and collegiate wrestlers is well studied, little is known about weight loss behavior in high school boxers. Because the weight loss methods used before competitions differ between individuals, weight loss behavior is worth analyzing on an individual level. Rapid weight loss (RWL) is an especially important topic because RWL has potential negative effects on exercise performance and/or athletes’ health and growth.
PURPOSE The purpose of the present study was to refine methods for evaluating whether weight loss strategies are RWL, and to examine the individual weight loss behaviors of high school amateur boxers.
METHODS Thirty-two high school amateur boxers aged 16-17 years who competed in a local tournament participated in a self-assessment survey designed to assess weight loss behaviors.
RESULTS Complete surveys were received from 26 of the 32 boxers. Nineteen of the 26 boxers reported losing weight to compete in the tournament. Sixteen reported engaging in rapid weight loss (RWL), defined as losing >1.5% body weight per week. After analyzing weekly weight loss quantities, two additional boxers were categorized as RWL. The RWL boxers lost 4.2 ± 1.7 kg (6.8% ± 2.5% of their initial body weight) during 22 ± 9 days.
CONCLUSION This study demonstrated that because boxers engage in longer weight loss periods than other weight-classed athletes, RWL should be assessed using not only the total amount of weight lost and the number of days engaged in weight loss, but also the amount of weight lost weekly.

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There are few detailed investigations of the parents’ academic background and physical growth of female students in vocational high school in South Korea. In this study we investigated the characteristics of physical growth of young women in a vocational high school viewed from the academic backgrounds of both parents, as well as physical similarities from the correlation between the physiques of the subjects and both parents. We also examined the composition of the status of delayed and early menarche in the subjects by applying the delayed menarche evaluation system constructed by Fujii (2008). The subjects were 59 students of a vocational high school for whom longitudinal physical growth data were obtained. A survey including parents’ academic background and physique was also conducted. The wavelet interpolation method was applied to longitudinal growth data for height and the delayed menarche evaluation system was applied to the derived age at maximum peak velocity of height and the age at menarche. In terms of physical growth associated with parents’ academic background, the results suggest that a girl’s rate of maturation is slightly faster when parents have college educations. It may be that this difference is affected by the economic status of the family. With regard to the correlation between the physiques of parents and the physical growth of girls, a relationship was seen between mothers and girls and a canalization effect was surmised. Moreover, a trend for delayed menarche was seen in the subjects in this study. Mental and physical stress was conjectured from this, indicating that it is an effect of the living environment of the young women in the growth process.

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