Masatoshi Nakamura

Introduction Proprioceptive neuromuscular facilitation (PNF) stretching is widely used to increase range of motion, but its underlying mechanisms are not well understood. This experimental, parallel group design study investigated the acute effects of PNF stretching on rectus femoris muscle stiffness and explored a potential dose-response relations...

Background/Objectives: the purpose of this study was to determine the contributions of mechanical, neural, morphological, and muscle quality factors on individual differences in the maximal ankle dorsiflexion range of motion (ROM). Methods: A sample of 41 university students performed passive-dorsiflexion and morphological measurements. In the pass...

Background Previous injury and physical examination data collected by a physiotherapist were reviewed to investigate the causes of injury among competitive swimmers. Each swimmer received an injury improvement exercise program based on their injury history and physical examination findings. Purpose The purpose of this study was to identify trends...

Introduction Clinically, knowing whether a static stretching (SS) intervention program conducted for several weeks can reduce passive muscle stiffness is important. Still, only a few previous studies have evaluated the chronic effects of an SS intervention program in older adults, and the potential relationship between ROM changes and muscle stiffn...

Introduction Traditional set (TS), paired-set (PS), and super-set (SS) are used as resistance training methods. However, the effects of these methods on muscle fatigue (muscle strength and training volume) are not clear. The purpose of this study was to compare the effects of TS, PS, and SS on the muscle fatigue of the hamstrings and quadriceps. M...

Context Joint position sense may be related to increased range of motion (ROM) with static stretching (SS). Purpose The purpose of this study was to examine the relationship between the increased ROM and stretch tolerance, passive stiffness, and joint position sense in the acute effects of SS, including cross-education and non-local effects. Meth...

The acute effects of a foam rolling intervention on lactate clearance and the impaired executive function associated with fatigue after high-intensity exercise remain unclear. This study examined whether foam rolling is an effective tool for fatigue recovery. Eighteen healthy adults without consistent exercise habits participated in this study. Par...

Introducation This study aimed to clarify whether or not the prolonged effect of a 180-s static stretching (SS) exercise could be maintained for a longer period by performing an additional short-term (15-s) SS exercise following a 15-min rest. Methods The participants were 15 healthy untrained adult males in three conditions: (1) SS condition (180...

Introduction In the early postoperative period after total knee arthroplasty (TKA), joint range of motion (ROM) limitation and increased stiffness due to pain are commonly observed. Previous studies have reported that a single bout of foam rolling (FR) can acutely increase ROM and pain threshold on the contralateral (non-intervention) side in healt...

Currently, there is inadequate evidence on the effects of combined rehabilitation and nutritional therapy for patients with multimorbidity. Therefore, in this report, we describe a case of combined rehabilitation and nutritional therapies with favorable outcomes in a patient with duplicated musculoskeletal and cerebrovascular diseases. An 80-year-o...

Purpose It is difficult to measure maximal isokinetic eccentric (ECC) muscle strength in the sports field. This study aimed to investigate whether elbow isometric (ISO) flexion muscle strength or muscle thickness (MT) can be used to estimate elbow ECC flexion muscle strength. Material and methods Maximal muscle strength and muscle thickness (MT) we...

Explosive movements requiring high force and power outputs are integral to many sports, posing distinct challenges for the neuromuscular system. Traditional resistance training can improve muscle strength, power, endurance, and range of motion; however, evidence regarding its effects on athletic performance, such as sprint speed, agility, and jump...

Background The Nordic hamstring exercise (NHE) is useful for preventing hamstring strain injuries. However, its adoption rates in the sports field are currently low, necessitating a safe and efficient introduction. Hypothesis/Purpose The purpose was to examine the relationship between the eccentric force during the NHE and the one repetition maxim...

Background This study aimed to compare and examine the local and non-local effects of a foam rolling (FR) and static stretching (SS) intervention applied to the plantar flexor (PF). Methods Fourteen female participants were investigated. Each participant underwent three conditions in a random order at least 48h apart and at the same time of the da...

Background Clinicians and researchers are beginning to pay attention to the importance of the intrinsic foot muscles (IFMs). Among IFMs, the abductor hallucis (AbH) is associated with foot disorders. However, so far no method for assessing the strength of the AbH has been established. In addition, previous studies have shown increased IFM activity...

Background Interventions using vibration stimulation have been recognized for their potential for increasing range of motion (ROM) without compromising muscle strength. Handheld vibration massagers can efficiently deliver vibration therapy to the shoulder joint and may be a potential treatment. Purpose To evaluate the effects of vibration massage...

Kasahara, K, Konrad, A, Murakami, Y, Thomas, E, and Nakamura, M. Comparison of the effects of a roller massager intervention on the rectus femoris between lengthened and slack positions. J Strength Cond Res XX(X): 000–000, 2024—A roller massager (RM) is a type of foam rolling device, which previous studies have shown to be effective for acutely dec...

Purpose Previous meta-analysis studies concluded that static stretching intervention cannot decrease all-cause injury in healthy active individuals. On the other hand, static stretching intervention may decrease muscle injury, but the evidence has not been integrated. The aim of this study was to systematically review the papers and analyze the pre...

Our previous study showed that daily six maximal eccentric contractions that were performed 5 days a week for 4 weeks increased maximal voluntary isometric (MVC‐ISO), concentric (MVC‐CON), and eccentric contraction (MVC‐ECC) strength of the elbow flexors and muscle thickness of biceps brachii and brachialis (MT) by 8.3 ± 4.9%, 11.1 ± 7.4%, 13.5 ± 1...

Decreased attentional function causes problems in daily life. However, a quick and easy evaluation method of attentional function has not yet been developed. Therefore, we are searching for a method to evaluate attentional function easily and quickly. This study aimed to collect basic data on the features of electroencephalography (EEG) during atte...

Takeuchi, K, Nakamura, M, Matsuo, S, Samukawa, M, Yamaguchi, T, and Mizuno, T. Combined effects of static and dynamic stretching on the muscle-tendon unit stiffness and strength of the hamstrings. J Strength Cond Res 38(4): 681–686, 2024—Combined static and dynamic stretching for 30 seconds is frequently used as a part of a warm-up program. However...

Introduction Walking is a popular exercise but does not increase lower limb muscle strength and balance. We hypothesized that muscle strength, physical and cognitive function would be improved by inserting lunges in conventional walking. Methods Eleven regular walkers (54–88 years) who had more than 5000 steps in exercise walking a day at least 5...

This study aimed to investigate the correlation between the passive muscle stiffness of the pectoralis major muscle pars clavicularis (PMc) and shoulder extension range of motion (ROM) in both male and female participants. Thirty-nine (23 male/16 female) physically active and healthy participants volunteered in this study. After a standardized warm...

Recently, percussive massage (PM) intervention using a handheld percussive massage device, namely a massage gun, has been used as an easy way to perform vibration functions. Additionally, a product has been developed that allows PM intervention and heat application to be performed simultaneously. Thus, this study aimed to compare the acute effects...

Purpose Static stretching (SS) improves flexibility but may impair the accuracy of joint position sense. Therefore, this study aimed to investigate the acute effects and time course of SS on the accuracy of joint position sense, range of motion (ROM), and muscle–tendon unit (MTU) stiffness. Methods This study randomly assigned 16 healthy, young ma...

Acute effects of resistance training at different range of motions on plantar flexion mechanical properties and force, Journal of Sports Sciences, ABSTRACT The effects obtained from resistance training depend on the exercise range of motion (ROM) performed. We aimed to examine the acute effects of different exercise ROM resistance training on the p...

Purpose The effects foam rolling (FR) intervention on lactate clearance and the impaired executive function associated with fatigue after high-intensity exercise remain unclear. This study examined whether FR is an effective tool for fatigue recovery. Methods Eighteen healthy adults (10 males, 8 females; 21.8±1.7 years) without consistent exercise...

Background Physical activity plays an important role in the management of blood glucose levels. However, compelling evidence exists only for aerobic and resistance training. In this review, we aimed to identify the potential effects of stretching exercises on blood glucose levels. Methods A systematic literature search was performed using the foll...

Recently, Foam Rolling (FR) and Vibration Foam Rolling (VFR) have attracted attention in sports and rehabilitation fields. Previous studies have shown that FR and VFR acute interventions effectively increase the range of movement (ROM) and decrease tissue hardness. For application to sports and rehabilitation, it is necessary to compare the acute a...

Previous training studies with comprehensive stretching durations have reported that an increase in range of motion (ROM) can be related to decreases in muscle stiffness. Therefore, the purpose of this study was to analyze the association between the passive muscle stiffness of three muscle groups (triceps surae, quadriceps, hamstrings) to the resp...

Foam rolling (FR) intervention has recently attracted attention in sports and rehabilitation settings. However, the effects of FR using different rolling durations have not been fully clarified. Thus, this study focused on FR durations and examined the acute and prolonged (i.e., 20-min; 40-min, 60-min) effects of different FR intervention durations...

Purpose Nordic hamstring exercise (NHE) and razor hamstring curl (RHC) are usually performed to train hamstring eccentric contraction strength. However, it is unclear whether there are differences in the intensity of the two methods and the amount of loading on each muscle. Therefore, this study was conducted using peak eccentric force and each mus...

A Cold therapy is widely recognized as a prescription for acute-phase recovery in athletes. However, it has been suggested that vasoconstriction caused by cooling may, in fact, delay the recovery process after exercise. Therefore, we are researching a new cooling method that involves supplementing ice baths with carbon dioxide gas, which has vasodi...

The usefulness of Foam Roller (FR) even without a rolling stimulus (e.g., static compression with or without dynamic joint movements) has been recently demonstrated; however, the different effects of these methods remain unclear. Thus, this study aimed to compare and investigate the effects of such FR intervention methods on knee extensors. The dom...

Background A better understanding of the network responses of cortical activities during rest and cognitive tasks is necessary. Therefore, in this study, we aimed to evaluate cerebral activities during attentional tasks by using mobile electroencephalography, identifying the types of attentional components and brain waves. Methods In this experime...

Different methods can be used to assess muscle hypertrophy, but the effects of training on regional changes in muscle size can be detected only using direct muscle measurementssuch as muscle thickness, cross-sectional area, or volume. Importantly, muscle size increases vary across regions both within and between muscles following resistance trainin...

Muscle echo intensity, as measured by ultrasonography, could be used as a new marker of functional performance in older populations. This scoping review aimed to present evidence on the utility of muscle echo intensity as determined by ultrasonography for assessing functional performance in older adults. The eligibility criterion included observati...

Context: Nordic hamstring strength (NH strength) and single leg bridge test (SLBT) scores are used to predict the risk of hamstring strain injury. Although NH strength and SLBT scores may be related, the relationship between NH strength and SLBT score remains unknown. Objectives: This study investigated the relationship between NH strength and S...

Background: The aim of this manuscript is to investigate if stretching exercise administration order may influence outcomes pertinent to range of movement (ROM). Methods: A total sample of 108 participants was randomized into five groups. Eight sets of unilateral static stretching (SS) of 30s duration each with a 30s rest were administered to th...

Static stretching can increase the range of motion of a joint. Muscle-tendon unit stiffness (MTS) is potentially one of the main factors that influences the change in the range of motion after static stretching. However, to date, the effects of acute and long-term static stretching on MTS are not well understood. The purpose of this meta-analysis w...

Static stretching (SS), foam rolling (FR), and a combination of both are used as warm-ups for sports and training. However, no reports have compared or examined the warm-up effects of short-term interventions (i.e., 30-s). Therefore, this study was designed to compare and examine the effects of short-term SS, FR, and SS+FR on knee extensors. The do...

Background: The findings of previous studies support the efficacy of cold-water immersion (CWI) with carbon dioxide (CO2) in enhancing muscle blood flow and maintaining aerobic performance efficiency. We hypothesize that the addition of hydrogen gas (H2), known for its antioxidant properties and role in inflammation regulation, to C-CWI can enhance...

Increasing muscle strength and cross-sectional area is of crucial importance to improve or maintain physical function in musculoskeletal rehabilitation and sports performance. Decreases in muscular performance are experienced in phases of reduced physical activity or immobilization. These decrements highlight the need for alternative, easily access...

Static stretching can increase the range of motion of a joint. Muscle tendon unit stiffness (MTS) is potentially one of the main factors that influences the change in the range of motion after static stretching. However, to date, the effects of acute and long-term static stretching on MTS are not well understood. The purpose of this meta-analysis w...

Purpose Our previous study showed that one 3-s maximal eccentric contraction a day performed 5 days a week for 4 weeks (5DW) increased maximal voluntary contraction (MVC) strength of the elbow flexors more than 10%. The present study examined whether muscle strength would still increase when the frequency was reduced to 2 days or 3 days per week....

Background One of the pain-related factors in rotator cuff tears (RCTs) is abnormal scapular motion, which is thought to be related to the levator scapulae muscle activation. Additionally, attention has recently focused on the peak systolic velocity (PSV) as one of the causes of pain, but blood flow outside of the vessels supplying the rotator cuff...

Static stretching (SS), foam rolling (FR), and a combination of both are used as warm-ups for sports and training. However, no reports have compared or examined the warm-up effects of short-term interventions (i.e., 30-s). Therefore, this study was designed to compare and examine the effects of short-term SS, FR, and SS+FR on knee extensors. The do...

Stretch training increases the range of motion of a joint. However, to date, the mechanisms behind such a stretching effect are not well understood. An earlier meta‐analysis on several studies reported no changes in the passive properties of a muscle (i.e., muscle stiffness) following long‐term stretch training with various types of stretching (sta...

Background/objective: In our previous laboratory experiment (room temperature of 25 °C), CO2-rich cool-water immersion (CCWI) suppressed subjects' core body temperature even during repeated exercise. It is unclear whether the suppression of body temperature elevation would also continue after CCWI in a hot outdoor environment. Herein we investigat...

It is known that a single bout of foam rolling (FR) or stretching can induce changes in range of motion (ROM) and performance in non-directly adjoining areas of the dorsal chain (i.e., remote effects). However, to date, it is not known if such effects exist following long-term interventions. Thus, the purpose of this study was to investigate the re...

Purpose Changes in elbow flexion torque and biceps brachii electromyogram (EMG) activity over 30 repetitive maximal voluntary concentric-only (CON-only), eccentric-only (ECC-only), and alternative concentric and eccentric (CON-ECC, 30 concentric + 30 eccentric) contractions were examined to compare their muscle fatigue profiles. Methods Fifteen he...

The application of thermal agents via hot packs is a commonly utilized method. However, the time-course changes in the range of motion (ROM), stretch sensation, shear elastic modulus, and muscle temperature during hot pack application are not well understood. This study aimed to investigate the time-course changes in these variables during a 20-min...

We investigate the effect of a 1-week comprehensive foam rolling (FR) intervention program on knee pain, range of motion (ROM), and muscle function in patients with TKA.Thirty patients with TKA were randomly allocated to FR (n = 15) or control (n = 15) groups. The control group received only regular physical therapy. Patients in the FR group perfor...

Algometers are commonly used to measure the pain-pressure threshold (PPT) in various tissues, such as muscle, tendons, or fascia. However, to date, it is not clear if the repeated application of a PPT assessment can adjust the pain thresholds of the various muscles. Therefore, the purpose of this study was to investigate the repeated application of...

Objectives: Older adults with total knee arthroplasty (TKA) have a limited range of knee joint motion due to pain and stiffness. A roller massager (RM) has recently been suggested to decrease pain and increase joint range of motion (ROM). Therefore, this study aimed to investigate the acute effect of RM intervention on pain and knee joint ROM in ol...

Background: The current literature on the chronic effects of static stretching (SS) exercises on muscle strength and power is unclear and controversial. Objective: To examine the chronic effects of SS exercises on muscle strength and power as well as flexibility in healthy individuals across the lifespan. Design: Systematic review with meta-analys...

A single bout of foam rolling (FR) can acutely increase joint range of motion (ROM) without detrimental effects on subsequent muscle performance. Similarly, long-term FR training can increase ROM, while muscle performance seems to be unaffected. Although the acute and long-term effects of FR on the treated muscle are understood, the impact of FR on...

Introduction: If the aim is to increase maximal strength (MSt) and muscle mass, resistance training (RT) is primarily used to achieve these outcomes. However, research indicates that long-duration stretching sessions of up to 2 h per day can also provide sufficient stimuli to induce muscle growth. In RT literature, sex-related differences in adapta...

Static stretching (SS) and dynamic stretching (DS) in combination with foam rolling (FR) have been attracting attention as warm-up routines in sports. However, the combined and intervention order effects of SS or DS and FR on flexibility, muscle strength, and jump performance are still unclear. Therefore, this study aimed to compare the combined ef...

We studied the preventive effects of heat or cold therapy after repeated eccentric contraction against torque reduction, muscle soreness, and range of motion (ROM) due to delayed-onset muscle soreness (DOMS). A total of 42 healthy male subjects were randomly allocated into three groups: the HEAT group received heat therapy using an ultra-short-wave...

Stiffness is a fundamental property of living tissues, which may be modified by pathologies or traumatic events but also by nutritional, pharmacological and exercise interventions. This review aimed to understand if specific forms of exercise are able to determine specific forms of tissue stiffness adaptations. A literature search was performed on...

Foam rolling (FR) and vibration foam rolling (VFR) interventions have received attention as pre-exercise warm-ups because they maintain performance and increase range of motion (ROM). However, the immediate and prolonged effects and the comparisons between FR and VFR interventions are unknown. Therefore, this study was designed to compare the effec...

Dynamic stretching for more than 90 seconds is useful for improving muscle strength, although dynamic stretching for 30 seconds or less is commonly used in sports settings. The effects of dynamic stretching are influenced by the speed and amplitude of stretching, but no study examined these factors for 30 seconds of dynamic stretching. Therefore, t...

There are many reasons for reduced physical activity leading to reduced maximal strength and sport-specific performance, such as jumping performance. These include pandemic lockdowns, serious injury, or prolonged sitting in daily work life. Consequently, such circumstances can contribute to increased morbidity and reduced physical performance. Ther...

The effects of static stretching are influenced by prescribed and applied loads of stretching. The prescribed load is calculated from the stretching duration and intensity, whereas the applied load is assessed from the force of static stretching exerted on the targeted muscle. No previous study has investigated the prescribed and applied loads of s...

The effects of thermotherapy on autonomic nervous system activity and subjective sensations of fatigue and arousal are unclear. This study compared the effects of capacitive and resistive electric transfer (Cret) interventions (deep thermotherapy) and hot packs (superficial thermotherapy) on autonomic nervous system activity in healthy young women...