Mika Saito

Juntendo University

Objective This study explored the interaction among ACTN3 R577X polymorphism, muscle damage, and post-exercise inflammatory response by assessing changes over time in serum creatine kinase and interleukin-6 levels. Design Ninety-five active Japanese participants (50 men and 45 women: 22.2 ± 2.3 years) who did not perform daily upper limb strength...

The greater muscle fiber cross-sectional area (CSA) is associated with greater skeletal muscle mass and strength, whereas muscle fiber atrophy is considered a major feature of sarcopenia. Muscle fiber size is a polygenic trait influenced by both environmental and genetic factors. However , the genetic variants underlying inter-individual difference...

This study sought to assess how post-game creatine kinase (CK) levels correlate with the number of sprints and the impact of the ACTN3 polymorphism on this response. This research constituted a descriptive/observational, retrospective cross-sectional study. DNA was extracted from blood samples for ACTN3 polymorphism genotyping. CK was measured 48 h...

Background: Sprint interval training (SIT) improves maximal aerobic and anaerobic performance, including oxygen uptake (VO2 max ), power output, and sprint performance. This study aimed to investigate the effect of SIT load on V̇O 2max in trained subjects. Methods: SIT was performed twice a week for three weeks by twenty-four trained men (aged:...

Individual differences in muscle strength recovery after eccentric exercise may be influenced by sex and genotype. A candidate genetic polymorphism associated with response during muscle recovery is the MMP3 gene rs522616 polymorphism, encoding matrix metalloproteinase (MMP-3). Here, we investigated the effect of the MMP3 gene rs522616 polymorphism...

The objective of this study was to investigate the effects of free weight and body mass‐based resistance training (RT) on muscle size and thigh intramuscular fat (IMF) in young and middle‐aged individuals. Healthy individuals (aged 30–64 years) were assigned to either a free weight RT group (n = 21) or a body mass‐based RT group (n = 16). Both grou...

Ginszt, M, Saito, M, Zięba, E, Majcher, P, and Kikuchi, N. Body composition, anthropometric parameters, and strength-endurance characteristics of sport climbers: a systematic review. J Strength Cond Res XX(X): 000-000, 2023-Sport climbing was selected to be part of the Summer Olympic Games in Tokyo 2021 with 3 subdisciplines: lead climbing, speed c...

The R577X polymorphism in the α-actinin-3 gene (ACTN3) is associated with muscle strength and power; there is an association between ACTN3 R577X polymorphism and range of motion (ROM). We examined the effect of the ACTN3 R577X polymorphism on ROM through meta-analysis and systematic review. Relevant studies published before April 14, 2022 were iden...

Purpose: This study investigated the effect of online home-based resistance exercise training on fitness, depression, stress, and well-being. A total of 67 individuals participated. Of them, 28 participants (13 men and 15 women, average age: 45.1 ± 12.2 years) performed the same exercise training online (n = 17), using Zoom, or in person (n = 11) i...

This study aimed to investigate the relationship between power-oriented genetic polymorphisms and weightlifting status, create a total genotype score (TGS), and validate the association between TGS models and power-oriented athletes. First, 192 weightlifters and 416 controls were studied, and 12 polymorphisms that have previously been associated wi...

Purpose The aldehyde dehydrogenase 2 (ALDH2) rs671 polymorphism, which is exclusive to the Asian population, is related to many diseases. A high reactive oxygen species production in mitochondria, and low muscle strength in athletes and non-athletes, has been observed, as our previous study demonstrated. The purpose of this research was to investig...

The rs671 polymorphism is associated with the enzymatic activity of aldehyde dehydrogenase 2 (ALDH2), which is weakened by the A allele in East Asians. We recently reported the association of this polymorphism with the athletic status in athletic cohorts and the muscle strength of non-athletic cohorts. Therefore, we hypothesized the association of...

Background: In this study, we examined the Sex difference of the effect of rest intervals on lifting velocity during resistance exercise. Methods: Twenty-two trained subjects (11 men and 11 women) were included. Each protocol consisted of 3 sets of 10 repetitions at 70% of 1- repetition maximum (1RM) with rest intervals of 90 s (R90), 150 s (R15...

The purpose of this study was to compare the frequency of COL1A1 rs1107946 polymorphism between sport climbers and controls from three ethnic groups (Japanese, Polish, and Russian) and investigate the effect of the COL1A1 rs1107946 polymorphism on the age-related decrease in flexibility in the general population. Study I consisted of 1929 healthy p...

Purpose: In this study, we examined sex differences in lifting velocity and blood lactate concentration during resistance exercise using different rest intervals (RIs). Methods: Twenty-two trained men (n = 11) and women (n = 11) completed different RIs resistance exercise sessions (90s (R90), 150s (R150), and 240s (R240)). All sessions consisted of...

A recent case-control study identified 28 DNA polymorphisms associated with strength athlete status. However, studies of genotype-phenotype design are required to support those findings. The aim of the present study was to investigate both individually and in combination the association of 28 genetic markers with weightlifting performance in Russia...

This study aimed to investigate the ACTN3 R577X, ACE I/D, CKM rs8111989, and TRHR rs7832552 genotypes in climbers and controls in three ethnicities. The study consisted of 258 climbers (Japanese, n = 100; Polish, n = 128; Russian, n = 30) and 1151 controls (Japanese: n = 332, Polish: n = 635, Russian: n = 184). Genotyping results were analyzed usin...

Online exercise is undoubtedly useful and important; however, chronic adaptations to online exercise, particularly strength gain, muscle hypertrophy, and cardiovascular parameters, remain unclear. We investigated the effect of online exercise training using Zoom on fitness parameters compared with the same exercises supervised directly. In the pres...

Sport climbing will become an official event at the 2020 Tokyo Olympics; it is a popular wilderness sport among athletes and amateurs. Our previous study suggested that the T1470A polymorphism (rs1049434) of the monocarboxylate transporter 1 (MCT1) gene is associated with athletic performance and physiological phenotypes. The purpose of this study...

The purpose of this study is to develop a video-based motion analysis method using OpenPose for evaluating the performance of sport climber. To evaluate the skills of sport climber quantitatively, we proposed three kinds of evaluation indices concerning the smoothness and stability of motion as well as the effort of arm. The result of experiment sh...

Homma, H, Kobatake, N, Sekimoto, Y, Saito, M, Mochizuki, Y, Okamoto, T, Nakazato, K, Nishiyama, T, and Kikuchi, N. Ciliary neurotrophic factor receptor rs41274853 polymorphism is associated with weightlifting performance in Japanese weightlifters. J Strength Cond Res XX(X): 000-000, 2020-At least 69 genetic markers are associated with power athlete...