Journal of Physical Fitness and Sports Medicine
Official journal of the Japanese Society Physical Fitness and Sports Medicine
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The Journal of Physical Fitness and Sports Medicine (JPFSM)
[Volume 14, Number 1 January 25, 2025]
Regular Article
- Received: October 4, 2023 / Accepted: February 28, 2024
Abstract
Arm-cranking exercises combined with electrical muscle stimulation (EMS) of the lower limbs at maximum intensity enhance vascular endothelial function. To bring this procedure into clinical application, we examined the effects of acute arm-cranking exercise combined with lower-extremity EMS at different intensities on vascular endothelial function. The study included eight healthy adult males. After resting in the supine position, arm-cranking exercises were performed at an intensity of 50% VO2 max for 20 min, and the lower limb received EMS under three trials: maximum intensity trial (A+100%EMS trial), 50% intensity trial (A+50%EMS trial), and 25% intensity trial (A+25%EMS trial). Flow-mediated dilation (FMD), which reflects vascular endothelial function, was measured before and after the procedure, and the normalized FMD (nFMD) was calculated. The mean nFMD before and 30 min after the exercise was 0.8±0.3 and 2.3±1.8, respectively, in the A+100%EMS trial and 0.9±0.4 and 1.4±1.0, respectively, in the A+50%EMS trial, indicating a significant increase after exercise under both trials. No changes were observed in the A+25%EMS trial. The combination of arm-cranking exercise and 50% intensity EMS appears to be a clinically applicable program for improving vascular endothelial function, even with reduced exercise intensity.
Short Communication
- Received: February 1, 2024 / Accepted: April 1, 2024
Abstract
Weight loss reduces visceral fat and improves glucose tolerance. Our previous study found that weight loss from 3 consecutive days of fasting led to deteriorated glucose tolerance, but it is not clear whether this was due either to the physiological stress associated with consecutive fasting or that fasting itself. This study aimed to compare the effects of repetitive or consecutive fasting on intra-abdominal fat mass and glucose tolerance in rats fed a high-fat diet. After 2 weeks of high-fat diet feeding, male Wistar rats were divided into three groups matched for body weight: one group continued to receive the high-fat diet ad libitum for 2 weeks (control, CON); the second group fasted for the last 3 days (consecutive fasting, CF); and the third group repeated 1-day fasting three times with a 6-day ad libitum feeding interval (repetitive fasting, RF). Compared with the CON group, the intra-abdominal fat mass was significantly lower in the CF group after the intervention period, and there was a tendency for lower values in the RF group. During the oral glucose tolerance test, plasma glucose level was significantly higher in both fasting groups compared with the CON group, while that in the CF group was significantly higher than that in the RF group. Compared with the CON group, the CF group had significantly lower plasma insulin level, with a tendency for lower levels in the RF group. These findings suggest that even when fasting days are dispersed over multiple occasions, insulin secretion capacity may decrease in a similar manner to consecutive fasting, leading to a deterioration in glucose tolerance.
Regular Article
- Received: December 26, 2023 / Accepted: April 23, 2024
Abstract
The mitochondria are highly plastic organelles. Exercise training alters mitochondrial dynamics (mitochondrial fission and fusion) in skeletal muscles and improves overall mitochondrial function by altering mitochondrial morphology and forming new networks. However, changes in mitochondrial dynamics over time during exercise have not previously been observed. In the present study, we examined the changes in mitochondrial fission and fusion protein expression in rats over four weeks of endurance swimming training. The expression of the GTPase protein dynamin-related protein 1 (Drp1), a mitochondrial fission protein, increased during the early phase of the training period. In contrast, the expression of optic atrophy type 1 (OPA1), a mitochondrial fusion protein, was increased in the late phase of the training period. These data suggest that mitochondrial fission was increased in the early phase, and mitochondrial fusion was initiated partially in the late phase, of the training period. In conclusion, mitochondrial dynamics may be modulated depending on the phase of muscular adaptation to exercise training. This modulation contributes to enhanced mitochondrial function in skeletal muscle.
[Volume 14, Number 2 March 25, 2025]
Regular Article
- Received: January 15, 2024 / Accepted: April 24, 2024
Abstract
Glucose has been reported to reduce the expression of L-type amino acid transporter 1 (LAT1) protein in C2C12 myocytes. We therefore hypothesized that increased dietary carbohydrate and energy intake would reduce LAT1 protein expression in rodent skeletal muscle. Here, we tested this hypothesis. In Experiment 1 to examine the effects of dietary carbohydrate intake, male Sprague Dawley (SD) rats were divided into low-carbohydrate (low-CHO) and high-carbohydrate (high-CHO) diet groups. Each group was fed a low-CHO (20% carbohydrate) or high-CHO (70% carbohydrate) diet, respectively. Total energy intakes of both groups were matched by pair feeding. In Experiment 2 to examine the effects of dietary energy intake, rats were divided into low-Energy diet (fed 68% of ad libitum energy intake) and high-Energy diet (ad libitum) groups. After 7 days of dietary manipulation, the lower leg muscles on one side were percutaneously stimulated and subjected to one acute bout of resistance exercise. The contralateral leg muscle served as an internal control. We collected gastrocnemius muscle 6 h after contraction. In both Experiments 1 and 2, when results were analyzed by two-way analysis of variance, no main effect of diet on LAT1 protein concentration was observed. There was also no main effect of resistance exercise, or no interaction between diet and exercise. These results do not support our hypothesis that increased dietary carbohydrate and energy intake reduce LAT1 protein expression in rodent skeletal muscle. Furthermore, diet may not affect the effects of resistance exercise on LAT1 protein expression.
Regular Article
- Received: January 26, 2024 / Accepted: April 24, 2024
Abstract
This study aimed to prospectively record the occurrence of adverse events and near-misses during sports in middle-aged and older adults who voluntarily engaged in sports in the community and to clarify the frequency and characteristics of such events. The participants comprised 14 groups (14 sports) of middle-aged and older adults who voluntarily played sports in Sakae Ward, Yokohama. The follow-up period was 14 months (November 1, 2022, to December 31, 2023). Representatives of the target groups reported once a month to Sakae Ward via postcards regarding the status of their activities and the occurrence of adverse events and near-misses. The survey items included the age of the main participants in each group, number of activities during the month, duration of each activity, number of participants per activity, adverse events, and near-misses during sports. During the 14-month observation, eight adverse events and two near-misses were reported in the 14 groups, mainly comprising middle-aged and older adults. Of the eight adverse events, four were falls, all occurring in those aged ≥70 years and triggered by environmental problems. In this study, there were only two near-misses compared to eight adverse events, suggesting that the participants may have been unaware of near-misses. Therefore, even for sports played by groups of residents, it is important to identify risks by assessing health conditions prior to exercise and to implement initiatives to foster safety awareness among participants, such as hazard prediction training.
Regular Article
- Received: January 15, 2024 / Accepted: May 8, 2024
Abstract
Sleep and nutrition play a crucial role for athletes, contributing to the quality of recovery, optimization of performance, as well as the preservation of health and injury prevention. This study aimed to explore the potential relationships between sleep quality, nutritional status, and dietary habits among Moroccan male professional footballs players during the competitive period, while examining the influence of sleep quality on nutritional behaviors. Methods: This descriptive research included 49 professional male football players. Sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI) to differentiate “good sleep” and “poor sleep” groups. Dietary intake was collected using the 24-hour recall and analyzed by validated nutritional software to obtain data on energy intake and dietary frequency.The results reveal that 36 participants are classified as having "Good Sleep" and 13 as "Poor Sleep quality." With a significant difference (4.0 ± 0.2 vs. 6.9 ± 0.9, p < 0.001), consecutively. The correlation study between the (PSQI score) and nutritional status variables has revealed significant associations: a negative correlation with total energy intake (TEI) (r = -0.687, p < 0.01), carbohydrates intake (CHO g/kg BM) (r = -0.499, p < 0.01); and well as (CHO%) and (PRO%) ratios (r = -0.294, p < 0.05), (r = -0.292, p < 0.05) consecutively. On the other side, the PSQI demonstrates a positive correlation with the (FAT%) and Fats and butter. Conclusions These results suggest an association between sleep quality and dietary intake, indicating a potential influence of sleep quality on dietary choices.
[Volume 14, Number 3 May 25, 2025]
Regular Article
- Received: January 12, 2024 / Accepted: May 8, 2024
Abstract
Lower baseline neurocognitive ability could be a risk factor for anterior cruciate ligament (ACL) injuries. We investigated the effects of high-intensity exercise (HIE) on neurocognitive function in athletes, and if any changes in neurocognitive function after the HIE had effects on an unanticipated cutting motion. Fourteen collegiate female athletes performed a bicycle ergometer HIE exercise at 80% of their heart rate reserve. Neurocognitive function was evaluated by the Stroop Interference Test (SIT) pre- and post-HIE. Biomechanical variables were captured using a motion analysis system while participants performed side-step cutting tasks in anticipated and unanticipated conditions. Participants were divided into two groups according to the changes of SIT scores after HIE: increased performers (IP; n = 7) and decreased performers (DP; n = 7). The average SIT score of the IP group significantly increased, while that of the DP group significantly decreased after the HIE (Paired t-test, P < 0.001). The main effect of the HIE using repeated-measures ANOVA, was a significant decrease in peak knee valgus moment (pre: anticipated-condition − 0.1 ± 0.1Nm/kg, unanticipated 0.0 ± 0.2Nm/kg; post: anticipated 0.0 ± 0.1Nm/kg, unanticipated 0.1 ± 0.2Nm/kg, P = 0.024) and peak ground reaction force (pre: anticipated 3.3 ± 2.1%BW, unanticipated 3.8 ± 2.1%BW; post: anticipated 3.1 ± 3.4%BW, unanticipated 3.6 ± 3.6%BW, P = 0.035) only in the IP group. The athletes with improved neurocognitive functions had decreased the biomechanical ACL injury risk factors during the side-step cuttings. Improving neurocognitive function may contribute to ACL injury prevention.
Short Communication
- Received: February 5, 2024 / Accepted: May 9, 2024
Abstract
This study aimed to investigate the differences in exercise load due to variations in lower limb weight during stair ascent and descent. The study involved 10 healthy adult men and women without respiratory or circulatory diseases (five men and five women). Using a respiratory gas analysis device, the participants performed stair climbing under three conditions: 1) full weight, 2) half (partial) weight-bearing, and 3) non-weight-bearing. The maximum oxygen uptake during stair climbing was defined as the peak oxygen uptake. Additionally, the time required for ascent and descent was measured using a stopwatch, and heart rate and perceived fatigue at the end were assessed using the Borg scale. Peak oxygen uptake and Borg scale scores significantly increased during ascent and descent under the non-weight-bearing condition compared to those under the full weight-bearing and half-weight-bearing conditions. The required time was significantly extended under the half-weight-bearing and non-weight-bearing conditions compared to that under the full-weight-bearing condition. Therefore, when stair ascent and descent are necessary during a period requiring the use of both crutches, it is considered desirable to perform them only after at least half-weight-bearing condition or more is permitted, as this approach results in a considerable reduction in load.
Regular Article
- Received: March 4, 2024 / Accepted: May 23, 2024
Abstract
This study assessed the effects of a rugby-specific concussion awareness program on improving the recognition of relevant symptoms and knowledge of concussion in male collegiate rugby union players. Thirty-one collegiate rugby union players from Japan were offered a concussion awareness program; they responded to a questionnaire assessing symptom recognition and knowledge of concussion three times (before, immediately after, and four weeks after the implementation of the program). Immediately after the program, the recognition score of suspected concussion symptoms was higher compared with before and four weeks later, when it was still higher than before but not statistically significant. In addition, more players selected the correct answers about rugby-specific concussion topics after the program. Our findings suggest that while concussion awareness is expected to improve immediately, this effect was not maintained after four weeks. Therefore, concussion awareness opportunities should be scheduled regularly, such as at the start of each season, before the beginning of the competition season, and when new players join the team.
[Volume 14, Number 4 July 25, 2025]
Regular Article
- Received: February 20, 2024 / Accepted: June 3, 2024
Abstract
During pregnancy, physiological insulin resistance increases due to endocrine factors secreted by the placenta. Gestational diabetes mellitus is an example of a common complication arising from this phenomenon, for which exercise therapy is used as standard treatment. While the acute effects of static stretching on blood glucose levels are known, the effects of dynamic stretching in a seated or supine position are unclear. This study investigated the effects of dynamic stretching in a seated or supine position on blood glucose levels in young adult women with post-load hyperglycemia wearing a maternity simulation jacket. We included 11 healthy women in the luteal phase of their menstrual cycles with blood glucose levels >140 mg/dL 30 min after glucose loading. Four exercise conditions were established: bed-stretching (BSt) involving dynamic stretching in a seated, supine, or lateral position, standing-stretching (SSt) involving dynamic stretching in a standing position, walking (W) involving treadmill walking at a comfortable speed, and control (C) involving sitting at rest. After fasting for 10–14 h, blood glucose levels were measured using self-monitoring blood glucose at baseline and every 15 min for 120 min thereafter. In the BSt and W conditions, the blood glucose levels, peaks, and area under the curve at 45 and 60 min after glucose loading were significantly lower than those in the C condition. Therefore, dynamic stretching in a seated or supine position suppressed blood glucose level elevation after glucose loading in young adult women with post-load hyperglycemia wearing a maternity simulation jacket.
Short Communication
- Received: May 2, 2024 / Accepted: June 21, 2024
Abstract
Problem addressed: Previous attempts have been made to superimpose ultrasound images (Overlapping Images Method). The merit of this method is that it enables capturing the entire morphology of the muscle and tendon in the longitudinal direction beyond the width of the ultrasound probe. However, the division points between tissues were identified visually, and the reliability of the measurement was not clarified. Experimental approach: This study identified the division points for the overlapping images method using the following two procedures: (1) visual-only identification and (2) a combination of visual and custom-built software-based identification. Finally, the reliability of the measurements for each procedure was examined by estimating the intra- and inter-rater correlation coefficients (ICC 1.1, ICC 2.1). The length of the Achilles tendon, muscle-tendon unit, and gastrocnemius muscle was measured using the overlapping images method for 19 volunteers. Main results and findings: The ICC 1.1 and ICC 2.1 scores for visual identification alone ranged between 0.61–0.91 and 0.70–0.93, respectively. The scores for the combination of visual and software-based identification ranged 0.90–0.99 and 0.58–0.96, respectively. Conclusions: The high intra- and inter-rater reliability in the overlapping images method was demonstrated in almost all measurements of the three tissue lengths and the applicability of overlapping images method was demonstrated. In particular, the intra-rater reliability was better when a combination of visual and custom-built software-based identification was used.
Regular Article
- Received: February 20, 2024 / Accepted: June 26, 2024
Abstract
Triathlon is an endurance sport that requires a high aerobic capacity. Previous studies demonstrated that lower-leg vascular conductance (VC) was associated with maximal oxygen uptake. However, it is unclear whether muscular VC is greater in triathletes versus untrained individuals. To test our hypothesis that VC in skeletal muscle is greater in triathletes relative to untrained peers and is associated with higher aerobic capacity in triathletes, this study investigated 10 male triathletes (21±1 years of age) and 8 untrained men (22±1 years). Triathletes exhibited greater maximal oxygen uptake than their untrained counterparts (61±6 vs. 39±6 mL/kg/min, P < 0.01), as well as lower heart rate (54±7 vs. 65±9 bpm, P < 0.01) and body fat (11±2 vs. 16±6 %, P = 0.03). There were no detectable intergroup differences in systolic (115±8 vs. 117±9 mmHg, P = 0.74), mean (83±6 vs. 86±8 mmHg, P = 0.30), or diastolic (62±6 vs. 65±7 mmHg, P = 0.49) blood pressure. Lower-leg blood flow (4.2±1.3 vs. 2.5±0.9 mL/dL/min, P = 0.01) and VC (0.05±0.01 vs. 0.03±0.01 mL/dL/min/mmHg, P = 0.02) based on venous occlusion plethysmography were greater in triathletes versus untrained men. Maximal oxygen uptake was correlated with lower-leg blood flow (r = 0.70, P < 0.01) and VC (r = 0.69, P < 0.01). These results demonstrate that lower-leg VC is higher in triathletes than in untrained individuals, and it may be associated with higher aerobic capacity in triathletes relative to untrained counterparts.
[Volume 14, Number 5 September 25, 2025]
Short Communication
- Received: April 18, 2024 / Accepted: July 22, 2024
Abstract
Purpose: This study investigated the changes in the physical activity of Japanese breast cancer survivors during and after the state of emergency declaration (SOED) due to the spread of COVID-19. Methods: Participants were survivors of stage I-IIa breast cancer diagnosed between the ages of 18 and 60 years who wore a wearable device (Fitbit Versa) before and after the SOED period. Outcomes included steps per day on weekdays and weekend days and holidays, sedentary time, and time spent engaged in various levels of physical activity. Results: Seventeen participants were included in the analysis. Steps per day decreased significantly from 8450 ± 905 steps before the SOED to 6085 ± 526 steps during, and 6871 ± 776 steps after the SOED on weekdays (p < 0.05). No difference in sedentary time was observed before, during, and after the SOED period on weekdays or weekend days, or holidays. Time spent engaged in light physical activity was significantly shorter on weekdays, decreasing from 251 ± 15 minutes before the SOED to 216 ± 15 minutes during, and 223 ± 16 minutes after the SOED (p < 0.05). Time spent engaged in moderate to vigorous physical activity was significantly shorter on weekdays before the SOED at 154 ± 39 minutes, dropping to 101 ± 29 minutes during, and increasing to 136 ± 38 minutes after the SOED (p < 0.05). Conclusion: Participants spent less time engaged in all levels of physical activity on weekdays during the SOED. Therefore, during lockdowns, it is important to maintain higher intensities of physical activity on weekdays. Because steps and time spent engaged in light physical activity did not recover after the SOED period, breast cancer survivors need to focus on these parameters after lockdowns while also paying attention to infection prevention.
Regular Article
- Received: June 7, 2024 / Accepted: September 12, 2024
Abstract
The optimization of descending motor commands from the central nervous system is essential for maximizing performance during short-distance running. Recent studies have shown that transcranial direct current stimulation (tDCS) can modulate central nervous system excitability and enhance exercise performance. Additionally, plyometric exercises are known as a measure to enhance instantaneous motor performance. However, the combined effects of tDCS and plyometric exercise remain poorly understood. Therefore, we investigated the combined effects of anodal tDCS and plyometric conditioning exercises on short-distance sprint running. Eleven university athletes were asked to perform a 20-meter sprint test both before (pre-test) and after tDCS (post-test). Before the pre-test, the participants engaged in jogging, stretching, and incremental 20-meter sprint exercises. After the pre-test, anodal tDCS was applied to the cortical leg area. Following tDCS, plyometric hopping exercises were performed, and a post-test was conducted. The intensity and duration of the stimulation were 2 mA and 15 min, respectively. Sham stimulations were performed on different days using the same experimental procedure. The post-test time was significantly shorter than the pre-test time in both the anodal and sham tDCS conditions. Further, the improvement rate in the post-test was significantly higher in the anodal tDCS condition than in the sham tDCS condition. These findings indicate that combined anodal tDCS and prior plyometric exercise can optimize descending motor commands and peripheral motor function, thereby improving short-sprint running performance.
Short Communication
- Received: June 18, 2024 / Accepted: September 19, 2024
Abstract
Few studies have compared the impact characteristics of modern American football helmet types. The purpose of this study was to measure and compare the collision biomechanics of the common Vicis Zero1 (2.27 kg) and Riddell Speedflex (2.09 kg) helmets. Linear drop tests were conducted from 1.52, 1.98, 2.59, and 3.05 m with a Hybrid III headform. The helmets were positioned crown-down and dropped in a manner that resulted in minimal pre-collision rotation. An 8-camera motion capture system recording at 300 Hz was used to verify that contact occurred to the region of the helmet immediately superior to the top of the facemask for each trial. Impact kinetics were recorded via a force plate sampling at 1800 Hz. Peak and mean accelerations (g) were calculated from initial contact until peak vertical ground reaction force (VGRF) was reached. Independent t-tests and effect sizes (Hedge’s g) were performed. The Speedflex helmet resulted in greater peak VGRF, peak acceleration, and mean acceleration (p=0.045, <0.001, and <0.001, respectively). Effect sizes were medium for VGRF (0.73) and large for peak (48.07) and mean (2.28) accelerations. These data indicate that the Zero1 helmet, which has a compliant outer shell, may lead to greater athlete safety by resulting in peak forces and accelerations of less magnitude as compared to helmets with rigid shell designs.
Regular Article
- Received: May 14, 2024 / Accepted: October 4, 2024
Abstract
Falls after total knee arthroplasty are common in knee osteoarthritis patients due to advanced age and implant-induced sensory function changes. We reported the influence of toe grip strength on falls in knee osteoarthritis patients. This study aimed to determine whether toe grip strength training after total knee arthroplasty is related to the screening assessment and incidence of falls. Elderly patients undergoing unilateral total knee arthroplasty were divided into toe grip strength training group and control group. Six types of training were conducted on bilateral toes. The primary outcomes were changes in toe grip strength and timed up and go test time from preintervention to 12 weeks post-intervention. Secondary outcomes involved several factors, including the occurrence of falls. The analysis included 37 participants in both groups. Toe grip strength training group had a shorter timed up and go test and stronger bilateral toe grip strength than control groups. The changes of timed up and go test time was significantly correlated with the changes of toe grip strength on the affected side. There were significantly fewer falls in toe grip strength training group than in control group between 3 and 12 months after total knee arthroplasty. toe grip strength training was useful in improving walking ability and preventing falls in postoperative total knee arthroplasty patients. The advantage of toe grip strength training is that it is an unoperated muscle function, so the intervention can be conducted safely without specialist supervision unless the toes are impaired.
[Volume 15, Number 1 January 25, 2026]
Regular Article
- Received: March 21, 2024 / Accepted: October 9, 2024
Abstract
Purpose: The aims of the present study were to determine whether short maximal pedaling at optimal load (Lopt) improved maximal anaerobic power (MAnP) with changes in force and/or velocity, and if a difference in training volume influenced training outcomes in physically active male students. This study also attempted to establish better measurements for evaluating adaptations to short sprints at Lopt. Methods: Fourteen students were randomly divided into either a one-set training (OST) group or a higher volume training (HT) group. The OST group performed a single 8-s sprint. The HT group repeated 8-s pedaling until a peak power was under 90% of that in the previous set twice. To determine MAnP, participants pedal as rapidly as possible for 8-s at three different loads before, in the middle of and after the 4-week training intervention. Results: A 2-way ANOVA revealed that MAnP similarly increased after 2 to 4 weeks of training for both groups. Optimal cadence (velocity factor) and Lopt (force factor) increased during the first and last 2 weeks of training, respectively. The extent of increase in peak power was significantly lower in the Wingate anaerobic test (6.5 ± 1.4 %) than in the 8-s maximal effort pedaling test at near-Lopt (11.5 ± 1.3 %). Conclusion: Four weeks of a single 8-s maximal effort pedaling at Lopt on a cycle ergometer increased MAnP as well as high volume training. The increase resulted from an improvement in the velocity factor in the first half and force factor in the latter half of training. Furthermore, a non-specific test to training load and duration may underestimate the extent of training-induced increase in power compared to a specific test that more closely resemble a training protocol.
Regular Article
- Received: July 8, 2024 / Accepted: November 14, 2024
Abstract
Despite the known health impacts of rapid weight loss (RWL) in athletes, effective mitigation strategies, especially nutritional ones, remain underexplored. This study aimed to investigate the effects of Lactiplantibacillus pentosus ONRICb0240-containing food (b240) intake on salivary secretory immunoglobulin A (SIgA) secretion in judo athletes undergoing RWL. Therefore, 17 male competitive college judo athletes were categorized into two groups: the b240 intake (active group; n = 9) and no b240 intake (control group; n = 8). Both groups engaged in 4 weeks of regular training followed by 1 week of RWL. The active group consumed b240 daily, every evening before dinner, throughout the 5-week experiment. Participants documented upper-respiratory symptoms (URS) and abdominal conditions during the study. Saliva samples were collected, and physical fitness tests were performed on each participant at 0 weeks (before intervention), 4 weeks (before weight loss), and 5 weeks (after weight loss). Results showed that salivary SIgA secretion was significantly decreased in the control group after weight loss compared to before the intervention (0 weeks, p < 0.05), while no significant changes were observed in the active group. Compared to the control group, URS decreased, and the percentage of days participants reported their abdominal condition as “good” increased in the active group (p < 0.05). These findings suggest that regular intake of b240 may be beneficial for reducing the frequency of URS among judo athletes, potentially due to better maintenance of salivary SIgA secretion during training and RWL.
Regular Article
- Received: August 21, 2024 / Accepted: December 10, 2024
Abstract
Heavy exercise training may negatively affect the gastrointestinal status of athletes, often leading to poor athletic performance and physical condition. The gut microbiome plays aa important role in the pathogenesis of gastrointestinal disorders. However, the relationship between the gut environment and conditions in athletes remains to be investigated. In this study, we aimed to determine the relationship between the gut microbiome, stool pattern, and the physical condition of elite athletes. A total of 92 elite athletes participated in this study, and their gut microbiomes, stool patterns, and physical conditions were evaluated. The gut microbiome was analyzed using 16S rRNA sequencing. The stool patterns and subjective physical conditions were evaluated using questionnaires. The participants were divided into better and poorer physical condition groups based on the median value of the physical condition score. The prevalence of abnormal stool patterns was significantly higher in the poorer condition group than that in the better condition group. The abundance of Faecalibacterium was significantly higher and that of Bifidobacterium was significantly lower in the better condition group than those in the poorer condition group. Principal component analysis revealed that the stool pattern could be explained by the Faecalibacterium abundance and the physical condition scores. Together, these findings suggest that the gut microbiome, especially the Faecalibacterium and Bifidobacterium abundance, affects the stool patterns and physical conditions of elite athletes, indicating that the gut microbiome may play a role in controlling the gastrointestinal environment affected by physiological stress such as intense exercise.