Effects of early sports specialization on landing and balance ability in female college basketball players.

Objectives: Early specialization in a single sport from childhood is associated with an increased risk for acute and overuse injuries. Conversely, experience in multiple sports may be associated with improved neuromuscular control and performance. Currently, early sports specialization remains poorly researched in Japan.

Immediate Effects of Calf Tissue Flossing on Ankle Joint Torque and Dorsiflexion Range of Motion in Healthy Individuals: A Randomized Controlled Crossover Trial.

Tissue flossing involves wrapping a rubber band around a muscle group for a few minutes while performing joint motion, enhancing ankle joint torque and range of motion. As limited ankle dorsiflexion range of motion and plantar flexion muscle weakness are risk factors for sports injury, assessing the therapeutic effects of tissue flossing is important. This study aimed to evaluate the immediate effects of calf tissue flossing on enhancing ankle joint torque and dorsiflexion range of motion.

Effects of muscle quantity, muscle quality, and phase angle on whole-body reaction time in 5164 adults aged 20-91 years.

Purpose: Muscle quantity, defined as appendicular lean mass (ALM); muscle quality, defined as the ratio of muscle strength to ALM; and bioelectrical impedance analysis (BIA)-derived phase angle (PhA) are determinants of physical performance. We examined whether muscle quality indices were significant predictors of the whole-body reaction time (WBRT) in healthy female and male adults aged 20-91 years.

Methods: Data from 5164 adults (2869 women and 2295 men; mean age ± standard deviation, 60.

Postoperative Rehabilitation Program for Increasing Muscle Mass in Patients With Hip Fracture: A Retrospective Study.

Background: Hip fractures are most likely to occur in older people, and after hip surgery muscle mass and the ability to perform activities of daily living often decline. In this study, we conducted inpatient rehabilitation after surgery for hip fracture and measured changes in muscle mass and physical performance.

Methods: We retrospectively analyzed patients aged 65 years or older who underwent surgery (prosthetic replacement or internal fixation) and inpatient rehabilitation for hip fracture at our hospital between August and December 2020.

The bioelectrical impedance analysis (BIA) international database: aims, scope, and call for data.

Background: Bioelectrical impedance analysis (BIA) is a technique widely used for estimating body composition and health-related parameters. The technology is relatively simple, quick, and non-invasive, and is currently used globally in diverse settings, including private clinicians' offices, sports and health clubs, and hospitals, and across a spectrum of age, body weight, and disease states. BIA parameters can be used to estimate body composition (fat, fat-free mass, total-body water and its compartments).

Age-related differences in glenohumeral internal rotation deficit, humeral retrotorsion angle, and posterior shoulder tightness in baseball players.

Background: Glenohumeral internal rotation deficit is generally recognized as a risk factor for throwing disability in baseball players. However, the pathology, timing of onset, role in the onset of humeral retrotorsion angle (HTA) and soft tissue extensibility (STE), and the relationship with age remain unclear. Therefore, the purpose of this cross-sectional study was to investigate age-related glenohumeral internal rotation deficit, HTA, and STE in Japanese baseball players and determine whether these factors correlate with throwing disability.

Association of Knee Extensor Muscle Strength and Cardiorespiratory Fitness With Bone Stiffness in Japanese Adults: A Cross-sectional Study.

Background: Knee extensor muscle strength and cardiorespiratory fitness (CRF) are major components of physical fitness. Because the interactive association of knee extensor muscle strength and CRF with bone health remains unclear, we aimed to investigate such association in Japanese adults.

Methods: Altogether, 8,829 Japanese adults (3,731 men and 5,098 women) aged ≥45 years completed the maximum voluntary knee extension test, submaximal exercise test, medical examination, and a questionnaire on lifestyle habits.

Effects of Different Exercise Conditions on Antioxidant Potential and Mental Assessment.

Exercise increases oxidative stress, leading the body to strengthen its antioxidant defenses, thus reducing the incidence of major diseases. As these associations are relatively unclear for ordinary levels of exercise for reduced stress, this study evaluated the effects of different exercise conditions on diacron-reactive oxygen metabolites (d-ROMs), biological antioxidant potential (BAP), and subjective mood. Forty-nine students (22.

Risk factors for throwing elbow injuries during pitching analyzed by simulation using human musculoskeletal model in youth baseball pitchers.

Background: Pitching mechanics are believed to be risk factors for throwing elbow injury. Thus, a prospective study of abnormal mechanics in youth baseball players is needed. This study aimed to analyze the ulnar collateral ligament during normal pitching using SIMM (Software for Interactive Musculoskeletal Modeling) for analysis and investigate the risk parameters of throwing elbow injuries in youth baseball players.

Effect of hip flexion angle on stiffness of the adductor longus muscle during isometric hip flexion.

This study examined the effect of hip flexion angle on the stiffness of the adductor longus (AL) muscle during isometric hip flexion. Seventeen men were recruited. Ten participants performed submaximal voluntary contraction at 0%, 25%, 50%, and 75% of maximal voluntary contraction (MVC) during isometric hip flexion after performing MVC at 0°, 40°, and 80° of hip flexion.

Return-to-play outcomes in high school baseball players after ulnar collateral ligament injuries: dynamic contributions of flexor digitorum superficialis function.

Background: Ulnar collateral ligament (UCL) injuries are common in baseball pitchers. The purpose of this study was to evaluate changes to medial elbow joint laxity under valgus stress, as well as under valgus stress with flexor digitorum superficialis (FDS) contraction, and its ability to predict rehabilitation outcomes.

Methods: Sixty-one UCL injuries were diagnosed.

Neuromuscular activation pattern of lower extremity muscles during pedaling in cyclists with single amputation of leg and with two legs: a case study.

Objective: In Para-cycling competitions, cyclists with amputation of one-leg and no prosthesis, i.e., Division Cycle, Sport Class C2, perform pedaling movement on bicycle by unilateral leg.

Relationship of Cardiorespiratory Fitness and Body Mass Index with the Incidence of Dyslipidemia among Japanese Women: A Cohort Study.

Low cardiorespiratory fitness (CRF) and obesity are independent risk factors for dyslipidemia. We investigated the synergistic effects of CRF and obesity on the incidence of dyslipidemia among Japanese women. Of 7627 participants, 927 normolipidemic Japanese women completed a submaximal exercise test, medical examination, and a questionnaire on smoking and alcohol drinking.

Throwing Injuries in Youth Baseball Players: Can a Prevention Program Help? A Randomized Controlled Trial.

Background: Throwing injuries of the shoulder and elbow are common among youth baseball players.

Hypothesis: A prevention program will reduce the incidence of throwing injuries of the shoulder and elbow by 50% among youth baseball players.

Study Design: Randomized controlled trial; Level of evidence, 1.

Efficacy of a Prevention Program for Medial Elbow Injuries in Youth Baseball Players.

Background: Youth baseball players are at high risk for elbow injuries, which can lead to future functional disability.

Purpose: To evaluate the effectiveness of a prevention program to lower the risk of medial elbow injury in these athletes.

Study Design: Cohort study; Level of evidence, 2.

Physical Risk Factors for a Medial Elbow Injury in Junior Baseball Players: A Prospective Cohort Study of 353 Players.

Background: The physical risk factors for a medial elbow injury in junior baseball players are unknown.

Purpose: To identify the risk factors for an initial medial elbow injury in junior baseball players.

Study Design: Case-control study; Level of evidence, 3.

In Vivo Talocrural Joint Contact Mechanics With Functional Ankle Instability.

Background: Functional ankle instability (FAI) may involve abnormal kinematics and contact mechanics during ankle internal rotation. Understanding of these abnormalities is important to prevent secondary problems in patients with FAI. However, there are no in vivo studies that have investigated talocrural joint contact mechanics during weightbearing ankle internal rotation.

The effects of a semi-rigid brace or taping on talocrural and subtalar kinematics in chronic ankle instability.

Background: A semi-rigid brace or taping is often used to prevent giving-ways in the joint with chronic ankle instability (CAI). However, it remains unknown whether the application of a semi-rigid brace or taping modifies abnormal kinematics in CAI joints. The objective of this study was to determine if the application of a semi-rigid brace or taping of the ankle normalizes abnormal weight-bearing kinematics in CAI joints during ankle internal rotation in plantar flexion.

Change in the cross-sectional area of a patellar tendon graft after anterior cruciate ligament reconstruction.

The purpose of this study was to clarify the change in the cross-sectional area (CSA) of a patellar tendon graft after anterior cruciate ligament (ACL) reconstruction, and its relationship with postoperative knee laxity. Forty patients (25 men and 15 women) were included in this study. Intraoperative CSA measurements were performed with an instrumented areamicrometer, while a magnetic resonance imaging (MRI) evaluation was utilized for the assessment postoperatively.

Left ventricular chamber size predicts the race time of Japanese participants in a 100 km ultramarathon.

Objective: As a subanalysis of an echocardiographic study performed on 291 Japanese participants in a 100 km ultramarathon, to estimate predictors of race time.

Methods: A total of 247 male participants in a 100 km ultramarathon (age 20-73 years) were examined by echocardiography. Correlations between age, body surface area, monthly running distance, or echocardiographic variables and the race time were examined.

New upper limit of physiologic cardiac hypertrophy in Japanese participants in the 100-km ultramarathon.

Objectives: The goal of our study was to define the structural characteristics of the heart in Japanese 100-km ultramarathon runners.

Background: During screening of participants in a 100-km ultramarathon, we found some participants who had larger cardiac chambers than had ever been previously reported.

Methods: A total of 291 male participants in a 100-km ultramarathon age from 20 to 73 years were examined using echocardiography.

Rapid increase in plasma growth hormone after low-intensity resistance exercise with vascular occlusion.

Hormonal and inflammatory responses to low-intensity resistance exercise with vascular occlusion were studied. Subjects (n = 6) performed bilateral leg extension exercise in the seated position, with the proximal end of their thigh compressed at 214 +/- 7.7 (SE) mmHg throughout the session of exercise by means of a pressure tourniquet.