Former Olympians had remained on high bone mineral density for a long period: Consecutive checkup of the 1964 Tokyo Olympic Japanese contestants for over 50 years.

Introduction: We performed consecutive checkups of the 1964 Tokyo Olympic contestants every 4 years for 50 years. This study evaluated bone mineral density (BMD) and its related factors in former Tokyo Olympic athletes.

Objectives: The study population comprised 181 former Olympians (141 men and 40 women) who had undergone BMD measurement in at least one of the four checkups performed every 4 years since 2005.

Growth until Peak Height Velocity Occurs Rapidly in Early Maturing Adolescent Boys.

The timing and tempo of growth rate varies inter-individually during adolescence and can have an impact on athletic performance. This study aimed to determine the difference in growth rate for each maturity status. We combined data collected both retrospectively and prospectively from 78 adolescent boys aged 12 years old; growth charts were collected from their elementary school records, and the height of each participant was subsequently measured every six months over a period of two years.

Iron Metabolism following Twice a Day Endurance Exercise in Female Long-Distance Runners.

Iron deficiency anemia (IDA) and iron deficiency (ID) are frequently observed among endurance athletes. The iron regulatory hormone hepcidin may be involved in IDA and/or ID. Endurance athletes incorporate multiple training sessions, but the influence of repeated bouts of endurance exercise within the same day on iron metabolism remains unclear.

Utilizing hierarchical redundancy for accurate throwing movement.

Understanding how athletes reduce motor variability in redundant tasks contributes to improving sports performance and elucidating human motor control mechanisms. This study aimed to clarify how experienced basketball players use two hierarchical redundancies, ball-level and body-level, for accurate free-throw shooting as no study has simultaneously examined how these hierarchical redundancies are used. Experienced basketball players (intermediate-level and top-level) participated in a free-throw shooting experiment using a motion capture system under two conditions: with feedback (FB) and no-feedback (NF) conditions.

Forwards-backwards hand velocity induced by the upper trunk rotation in front crawl strokes and its association with the stroke frequency.

The aim of this study was to determine the contribution of the upper trunk rotation consisting of roll-pitch-yaw to hand velocity in the forwards-backwards direction during front crawl strokes and to investigate the association of forwards-backwards hand velocity induced by the upper trunk rotation with stroke frequencies. Fifteen skilled swimmers with retro-reflective markers performed front crawl strokes in a swimming pool where a motion capture system was set. Forwards-backwards hand velocity solely induced by the upper trunk rotation was determined during the performance.

Longitudinal Change of Forearm-Hand Inertia Value and Shoulder Musculature Using Dual X-ray Absorptiometry in Youth Japanese Baseball Players: Implications for Elbow Injury.

It is important to understand the timing of the maximum increase of forearm-hand inertia value and lean body mass (LBM) of the shoulder girdle musculature when elbow injury frequently occurs. This study aimed to clarify the discrepancies of those in youth baseball players. Forty-three male baseball players (8- to 14-years-old) participated in this study.

Plasma brain-derived neurotrophic factor and dynamic cerebral autoregulation in acute response to glycemic control following breakfast in young men.

We examined the acute impact of both low- and high-glycemic index (GI) breakfasts on plasma brain-derived neurotrophic factor (BDNF) and dynamic cerebral autoregulation (dCA) compared with breakfast omission. Ten healthy men (age 24 ± 1 yr) performed three trials in a randomized crossover order; omission and Low-GI (GI = 40) and High-GI (GI = 71) breakfast conditions. Middle cerebral artery velocity (transcranial Doppler ultrasonography) and arterial pressure (finger photoplethysmography) were continuously measured for 5 min before and 120 min following breakfast consumption to determine dCA using transfer function analysis.

Basketball players minimize the effect of motor noise by using near-minimum release speed in free-throw shooting.

The aim of this study was to clarify the strategy used by basketball players during free-throw shooting to improve performance in the presence of motor noise. Two possible hypotheses were examined: the players minimize the release speed to decrease signal-dependent noise or the players maximize the shot success probability by accounting for their variability. Eight collegiate players and one professional player participated in this study by attempting shots from the free-throw line using a motion capture system.

Effects of Taurine Supplementation on Vascular Endothelial Function at Rest and After Resistance Exercise.

High-intensity resistance exercise has been shown to increase arterial stiffness and reduce vascular endothelial function. Taurine supplementation has a favorable effect on maintaining vascular function. We had previously reported that taurine supplementation attenuated increases in resistance exercise-induced arterial stiffness.

Contribution of upper trunk rotation to hand forward-backward movement and propulsion in front crawl strokes.

The study aims to test three hypotheses: (a) the rotation of the upper trunk consists of roll, pitch and yaw of frequencies harmonic to the stroke frequency of the front crawl stroke, (b) the rotation of the upper trunk generates back-and-forth movements of the shoulders, which enhances the movements of the stroking arms, and (c) the angular velocities of roll, pitch and yaw are associated with hand propulsion (HP). Front crawl strokes performed by twenty male swimmers were measured with a motion capture system. The roll, pitch and yaw angles about the three orthogonal axes embedded in the upper trunk were determined as three sequential Cardan angles and their angular velocities were determined as the three respective components of the angular velocity.

Effects of Respiratory Muscle Endurance Training in Hypoxia on Running Performance.

Purpose: We hypothesized that respiratory muscle endurance training (RMET) in hypoxia induces greater improvements in respiratory muscle endurance with attenuated respiratory muscle metaboreflex and consequent whole-body performance. We evaluated respiratory muscle endurance and cardiovascular response during hyperpnoea and whole-body running performance before and after RMET in normoxia and hypoxia.

Methods: Twenty-one collegiate endurance runners were assigned to control (n = 7), normoxic (n = 7), and hypoxic (n = 7) groups.

Kinematics of Rugby Tackling: A Pilot Study With 3-dimensional Motion Analysis.

Background: Although improper tackling technique in rugby can affect the outcome of the tackle and lead to head, neck, and shoulder injuries, the effects of the height of the tackle or the side of the leading leg at the time of impact have not been investigated. Hypothesis/Purpose: The purpose was to characterize the trunk orientation at impact during various tackles. It was hypothesized that 3-dimensional motion analysis would be able to capture the critical kinematic differences in the 4 types of tackles studied.

How to Maintain Maximal Straight Path Running Speed on a Curved Path in Sprint Events.

This study aims to clarify the ideal technique for running on a curved path during sprinting events. Participants were twelve male track and field athletes including long jumpers and sprinters. The participants performed a 60-m sprint with maximal effort on straight and curved paths.

The prevalence of anemia in Japanese Universiade athletes, detected with longitudinal preparticipation medical examinations.

Background: No reports have evaluated the long-term trends of the prevalence of anemia in Universiade athletes using preparticipation medical examinations (PPMEs). We aimed to investigate the prevalence of anemia among Japanese Universiade athletes, using longitudinal PPMEs.

Methods: In this retrospective, observational study, athletes with published data from official reports of the Japanese delegation of the summer Universiade games between 1977 and 2011 were included, as were similar-aged nonathletes with published health data, extracted from official national reports from the Japanese Ministry of Health, Labour and Welfare.

Role of selected polymorphisms in determining muscle fiber composition in Japanese men and women.

Genetic polymorphisms and sex differences are suggested to affect muscle fiber composition; however, no study has investigated the effects of genetic polymorphisms on muscle fiber composition with respect to sex differences. Therefore, the present study examined the effects of genetic polymorphisms on muscle fiber composition with respect to sex differences in the Japanese population. The present study included 211 healthy Japanese individuals (102 men and 109 women).

Postexercise serum hepcidin response to repeated sprint exercise under normoxic and hypoxic conditions.

We determined the effects of repeated sprint exercise under normoxic and hypoxic conditions on serum hepcidin levels. Ten male athletes (age: 20.9 ± 0.

Iron Supplementation during Three Consecutive Days of Endurance Training Augmented Hepcidin Levels.

Iron supplementation contributes an effort to improving iron status among athletes, but it does not always prevent iron deficiency. In the present study, we explored the effect of three consecutive days of endurance training (twice daily) on the hepcidin-25 (hepcidin) level. The effect of iron supplementation during this period was also determined.

Appetite Regulations After Sprint Exercise Under Hypoxic Condition in Female Athletes.

Kojima, C, Kasai, N, Ishibashi, A, Murakami, Y, Ebi, K, and Goto, K. Appetite regulations after sprint exercise under hypoxic condition in female athletes. J Strength Cond Res 33(7): 1773-1780, 2019-The present study determined changes in appetite-regulating hormones and energy intake after high-intensity interval exercise (HIIT) under hypoxic conditions (HYP) in trained female athletes.

Elevated Serum Hepcidin Levels during an Intensified Training Period in Well-Trained Female Long-Distance Runners.

Iron is essential for providing oxygen to working muscles during exercise, and iron deficiency leads to decreased exercise capacity during endurance events. However, the mechanism of iron deficiency among endurance athletes remains unclear. In this study, we compared iron status between two periods involving different training regimens.

Maximal inspiratory mouth pressure in Japanese elite female athletes.

Maximal inspiratory mouth pressure (MIP) is a common measurement of inspiratory muscle strength, which is often used in a variety of exercises to evaluate the effects of inspiratory muscle training. The characteristics of MIP in elite female athletes remain unclear. This study aimed to determine the characteristics of MIP at rest in a variety of sport-specific elite female athletes.

Comparison of Site-Specific Bone Mineral Densities between Endurance Runners and Sprinters in Adolescent Women.

We aimed to compare site-specific bone mineral densities (BMDs) between adolescent endurance runners and sprinters and examine the relationship of fat-free mass (FFM) and nutrient intake on BMD. In this cross-sectional study, 37 adolescent female endurance runners and sprinters (16.1 ± 0.

The Effect of a 20 km Run on Appetite Regulation in Long Distance Runners.

The purpose of the present study was to investigate appetite-related hormonal responses and energy intake after a 20 km run in trained long distance runners. Twenty-three male long-distance runners completed two trials: either an exercise trial consisting of a 20 km outdoor run (EX) or a control trial with an identical period of rest (CON). Blood samples were collected to determine plasma acylated ghrelin, peptide YY (PYY) and other hormonal and metabolite concentrations.

Application of shear wave elastography for the gastrocnemius medial head to tennis leg.

Muscle strain of the gastrocnemius medial head mainly occurs at the musculotendinous junction (MTJ), and stiffness is a risk factor. Shear wave elastography (SWE) measures elasticity by determining the propagation velocity. The aim of this study was to measure the elasticity of the normal muscle and aponeurosis in the MTJ of the gastrocnemius medial head using SWE, thus obtaining information relevant to muscle strain at this point.