Strength and size relationships of toe flexor muscles in three different functional force production tasks.

: Toe flexor strength (TFS) has been determined to evaluate the toe flexor muscle function. However, it is unclear how strength and size relationships of toe flexor muscles vary depending on the toes intended for force production. We aimed to clarify this by examining the relationship between TFS and toe flexor muscle size, and hypothesized TFS produced by all toes (TFS-All), the great toe (TFS-Great) and lesser toes (TFS-Lesser) would be specifically associated with the size of the muscles specialized in each corresponding toe flexion.

The Anti-Obesity Effect of Fish Oil in Diet-Induced Obese Mice Occurs via Both Decreased Food Intake and the Induction of Heat Production Genes in Brown but Not White Adipose Tissue.

Omega-3 (ω-3) polyunsaturated fatty acids in fish oil have been shown to prevent diet-induced obesity in lean mice and to promote heat production in adipose tissue. However, the effects of fish oil on obese animals remain unclear. This study investigated the effects of fish oil in obese mice.

Stroke phase differences in the linear relationship between swimming velocity and vertical body position during front crawl.

We aimed to investigate whether a linear relationship exists between swimming velocity and vertical body position for each stroke phase in front crawl, and to determine whether there are differences in the velocity effect among the stroke phases. Eleven male swimmers performed a 15 m front crawl at various swimming velocities. The whole-body centre of mass (CoM) was estimated from individual digital human models using inverse kinematics.

Causes of Different Force-Velocity Relationships in Sprint Running Depending on Horizontal Loads and Profiling Methods.

Purpose: We aimed to clarify how the horizontal force-velocity (Fvh) relationship during over-ground sprint running differs with horizontal resistance loads and profiling methods (multiple- and single-trial methods).

Methods: Twelve males performed sprint running (one unresisted and five resisted) using a motorized loading device. During the trials, the ground reaction forces at every step were obtained using a 50 m force plate system.

Understanding sprint phase-specific training stimuli: a cluster analysis approach to overload conditions.

Introduction: This study analyzed the impact of various overload conditions on sprint performance compared to free sprinting, aiming to identify the loading scenarios that most closely replicate the mechanics of unresisted sprints across the full acceleration spectrum. While velocity-based training methods have gained popularity, their applicability is limited to the plateau phase of sprinting.

Methods: To address this limitation, we employed cluster analysis to identify scenarios that best replicate the mechanical characteristics of free sprinting across various overload conditions.

Support leg joint kinetic determinants of maximal speed sprint performance.

This study aimed to comprehensively demonstrate support leg joint kinetic determinants of maximal speed sprint performance. Ground reaction forces and marker coordinates attached to the body were measured in the maximal speed phase from 44 male sprinters. Then, three-dimensional leg joint torque, angular velocity and power were calculated.

Response of circulating fatty acid binding protein 4 concentration to low-intensity acute aerobic exercise is amplified in an exercise duration-dependent manner in healthy men.

Background: Circulating fatty acid-binding protein 4 (FABP4) influences cardiovascular disease and glucose metabolism. Acute aerobic exercise increases circulating FABP4 concentrations, but the factors underlying this effect in humans are unclear. We investigated the effect of exercise duration on circulating FABP4 concentrations in healthy men.

Revamping Pace Distribution: A Case Study on Elevating the Men's 400 m Track and Field Japanese National Record After 32 Years.

Chiba, Y, Sato, K, Yoshimoto, T, Ohnuma, H, Yamanaka, R, Takahashi, K, Kobayashi, K, Matsubayashi, T, and Takai, Y. Revamping pace distribution: A case study on elevating the men's 400 m track and field Japanese national record after 32 years. J Strength Cond Res XX(X): 000-000, 2024-Many studies have investigated the 400-m sprint, and the optimal pacing strategy is subject to debate.

Effects of probiotic supplementation with high-intensity interval training on cardiorespiratory endurance and metabolism in Middle-Aged Obese Women.

Introduction: High-intensity interval training (HIIT) has been shown to improve chronic diseases. Probiotics have been found to have similar effects. However, the additive effects of HIIT in combination with probiotics supplementation are unclear.

Distinctive features of bimanual coordination in idiopathic normal pressure hydrocephalus.

Background: Idiopathic normal pressure hydrocephalus (iNPH) is characterized by cerebrospinal fluid circulation disorders, and presents as gait and balance disturbances similar to those observed in other incurable neurological diseases. Although previous studies have reported deficits in bimanual coordination among patients with iNPH, these potential pathological characteristics have not received much attention to date. This study investigated the temporal characteristics of a bimanual finger-tapping task in patients with iNPH, focusing on within- and between-hand coordination.

The Effect of Bone Mechanical Stress Caused by Electrical Stimulation-Induced Muscle Contraction on Osteocalcin Secretion.

Electrical stimulation-induced muscle contraction (ESMC) has demonstrated various physiological benefits, but its effects on the secretion of undercarboxylated osteocalcin (ucOC), a bone-derived cytokine, remain unclear. This study explored the relationship between ESMC, bone strain, and ucOC secretion through two experiments. In the first, young male Fischer 344 rats were divided into three groups: low-frequency ES (LF, 10 Hz), high-frequency ES (HF, 100 Hz), and control (CON).

An Exploratory Vector Field Analysis of Ground Reaction Force During Maximum Sprinting Efforts in Male Soccer Players and Sprinters.

The ability to accelerate and attain high velocities is essential for both individual and team sport athletes. The purpose of this explorative study was to retrospectively analyze the ground reaction force using Statistical Parametric Mapping (SPM) vector field analysis, as traditional scalar analyses often fail to acknowledge the interdependence of force vector components. The ground reaction force vector and the scalar components (i.

Post-Exercise Hypotension after Exercising in Hypoxia with and Without Tart Cherry Supplementation.

Horiuchi Masahiro and Samuel J. Oliver. Post-exercise hypotension after exercising in hypoxia with and without tart cherry supplementation.

Effect of 1-Week Weight Loss While Maintaining Total Body Water on Jump Performance.

Jumping performance is influenced by body composition and excess fat mass impairs performance. Maintaining optimal fat mass and fat-free mass (FFM) is crucial for enhancing jump height. However, there is limited evidence on short-term weight loss programs that reduce fat mass without water restriction and their effects on muscle function and jumping performance.

Greater energy surplus promotes body protein accretion in healthy young men: A randomized clinical trial.

Background & Aims: Caloric overfeeding combined with adequate protein intake increases not only body fat mass but also fat-free mass. However, it remains unclear whether the increase in fat-free mass due to overfeeding is associated with an increase in total body protein mass. We evaluated the hypothesis that overfeeding would promote an increase in total body protein mass.

Interpreting the Projected Frontal Area in Front Crawl: Determining the Projected Frontal Area of Each Body Segment.

Purpose: This study aimed to provide evidence for the interpretation of the projected frontal area (PFA) during front crawl. To achieve this goal, we developed a method for calculating the PFA of each body segment using digital human technology and compared the pressure drag under two calculation conditions: a combination of the PFA with and without accounting for the horizontal velocity of each body segment.

Methods: Twelve competitive male swimmers performed a 15-m front crawl at 1.

Impact of Eccentric Exercise Interventions with Small and Large Ranges of Motion on Rat Skeletal Muscle Tissue and Muscle Force Production.

Eccentric training induces greater hypertrophy while causing more muscle damage than concentric training. This study examined the effects of small-range eccentric contractions (SR-ECCs) and large-range eccentric contractions (LR-ECCs) on muscle morphology, contractility, and damage in rats. Thirty male Fischer 344 rats were divided into five groups: small-range ECC single-bout (SR-ECC, = 4), large-range ECC single-bout (LR-ECC, = 4), SR-ECC intervention (SR-ECC, = 7), LR-ECC intervention (LR-ECC, = 8), and control (Cont, = 7).

Resistance training leading to repetition failure increases muscle strength and size, but not power-generation capacity in judo athletes.

Strength-trained athletes has less trainability in muscle size and function, because of their adaptation to long-term advanced training. This study examined whether resistance training (RT) leading to repetition failure can be effective modality to overcome this subject. Twenty-three male judo athletes completed a 6-week unilateral dumbbell curl training with two sessions per week, being added to in-season training of judo.

Factors associated with water consumption measured using the stable isotope techniques among Japanese adults: a cross-sectional study.

Background/objectives: While some dietary guidelines have established daily water requirements for adults, those for older adults are not well defined. Factors associated with water turnover (WT), indicating water requirements and preformed water (PW), referring to fluids consumed from food and beverages, remain poorly understood. Therefore, we aimed to investigate these factors in Japanese adults.

Differences in the Size of Individual Plantar Intrinsic Foot Muscles Between Ballet Dancers and Non-Dancers.

Introduction: In classic ballet, choreography often involves tiptoe standing. Tiptoe standing requires a high and stable foot arch structure, which is achieved by contraction of the plantar intrinsic foot muscles (PIFMs). Long-term repetitive loading with a specific movement can induce hypertrophic adaptation of the associated muscles.

Test-Retest Reliability of Movement Displacement during a 20-s Stepping-in-Place Test in Community-Dwelling Older Adults with and without Supportive Care.

Introduction: Our recent reports have shown that movement pattern and displacement assessed with an infrared depth sensor during a 20-s stepping-in-place test (ST) correlates with measures of balance and need for assistance in older individuals. This study investigated ST test-retest reliability in community-dwelling older adults with and without supportive care.

Methods: Two groups were included: those not participating (HO: n = 25, 74.