Publications by authors named "Harumi Hayashida"

Purpose: The facile manipulation of body weight in junior athletes has the potential to pose significant risks to their lifelong health. In judo, which is a weight class sport, pre-competition weight loss is widespread even among juniors, but information on the current situation is scarce, especially for female athletes, for whom it is important to provide adequate nutrition and enhance bone mass during the growth period, and the details of the current situation are not clear. Therefore, the purpose of this study was to determine the actual weight loss during the growth period in junior female judo athletes and its subsequent impact on their health.

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Numerous research studies have investigated the relationship between exercise, oxidative stress level, and condition in athletes who engage in intense training on a daily basis. However, it is known that oxidative stress is affected by exercise, sleep, and the psychological state, but there are only a few studies that have comprehensively examined oxidative stress based on the actual practice periods and living conditions of athletes. Therefore, our study aimed to explore the influence of three distinct training periods (short training period, intensive training period, and pre-competition periods) as well as life situations (sleep and number of steps) on oxidative stress levels (diacron reactive oxygen metabolites: d-ROMs) in high school judo athletes.

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Moderate-intensity exercise is considered to enhance immune function and to be useful for preventing acute upper respiratory infections and similar conditions. Many people practice low-intensity short-duration exercise with the expectation of a beneficial effect on immunocompetency. However, it is difficult to affirm the existence of definite evidence of such a benefit.

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The purpose of this study was to examine the effect of oral contraceptive (OC) use on salivary secretory immunoglobulin A (SIgA) levels at rest and in response to an acute bout of moderate-vigorous exercise during 2 phases of the 4-week OC cycle corresponding to different phases of the synthetic menstrual cycle. Ten healthy active females completed a cycling at 70% peak oxygen uptake for 45 min at 2 time points of an OC cycle: during the equivalent in time to the mid-follicular phase (day 8 ± 2) and the mid-luteal phase (day 20 ± 2). Timed unstimulated saliva samples were obtained before, immediately postexercise, and 1 h postexercise and analyzed for salivary SIgA.

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Background: Sex hormones are known to regulate some responses during exercise. Evaluation of the differences in exercise response with regard to menstrual cycle will help understand the menstrual cycle phase specific adaptations to exercise and athletic performance.

Methods: We investigated the effects of menstrual cycle phase and carbohydrate (CHO) ingestion on immune response during endurance exercise at 30°C.

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Although numerous sources of evidence show that regular physical activity is beneficial to health, most individuals do not engage in a sufficient amount of physical activity to meet the guidelines set out by expert panels. In addition, the minimum amount of physical activity associated with reduced cardiovascular disease risk markers is not clear in older adults. The purpose of this study was to determine the effects of a 12-week walking program involving an exercise volume below the current minimum physical activity recommendation on cardiovascular disease risk markers in older adults.

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The orexigenic peptide hormone ghrelin exerts potent inhibitory effects on pro-inflammatory cytokine release via the growth hormone secretagogue receptor-1a (GHS-R1a) on T cells and monocytes. As such, ghrelin is a promising therapeutic agent for the treatment of inflammatory conditions, but these effects depend on the availability of GHS-R1a. The aim of this study was to determine the effect of acute exercise on GHS-R1a expression on circulating CD14+ monocytes, total lymphocytes and CD3+ T cells.

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The purpose of this study was to determine the relationships among delayed-onset muscle soreness (DOMS), muscle damage and inflammatory responses to eccentric exercise and investigate the underlying mechanisms. Nine healthy males performed one-leg calf-raise exercise with their right leg on a force plate. They performed 10 sets of 40 repetitions of exercise at 0.

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The purpose of this study was to investigate the effects of low-volume exercise training (100 min/week) on oxidative stress and neutrophils activation markers in older adults. Twenty-eight older adults (age range 65-78 years) were assigned into control (n = 14) or exercise (n = 14) groups. The exercise program consisted of walking 30-60 min/session, 2 days each week for 12 weeks.

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