Journal of Functional Morphology and Kinesiology最新文献

Background: A rhythmic jumping task that does not require specialized equipment may represent a simple method to assess upper-lower-limb coordination in athletes. Previous studies have been limited to groups with relatively low coordination ability; thus, whether task performance reflects the ability level or remains reproducible over time is unclear. This study determined whether the rhythmic jumping task reflects coordination levels in high-level performers, verified its generalizability as an assessment tool, and evaluated its reproducibility over time. Methods: Twenty-eight female high school volleyball players who routinely engaged in coordination training were enrolled, and performed six rhythmic jumping tasks identical to those used in a previous study. Performance was evaluated using three indices: complete performance rate (successful completion of all four series), success rate of at least one series, and average number of successful series. Twelve participants were retested 1 year later to examine reproducibility. Results: The high-level group demonstrated an overall superior performance compared to the low-level group from a previous study. Easier conditions yielded higher success rates, whereas more difficult conditions yielded lower success rates. Retest results demonstrated reproducible performance patterns over time. Conclusions: The rhythmic jumping task appropriately reflected coordination ability: high-level performers outperformed low-level performers. The task maintained a consistent difficulty order and reproducible performance across groups and over time, supporting its validity and generalizability as a practical and reliable tool to assess upper- and lower-limb coordination in applied athletic settings and provides a foundation for its further refinement and application as a standardized coordination assessment method.

Objectives: To characterise multidomain physiological responses to a maximal cycling effort and identify consistent physiological responder profiles. A secondary objective was to compare professionals and amateurs and assess the practical value of these profiles for personalised monitoring and performance management. Methods: This observational study included 22 trained male cyclists (10 professionals, 12 competitive amateurs; age 27.6 ± 6.4 years; height 177.3 ± 5.5 cm; weight 65.5 ± 4.1 kg). Participants performed a maximal 20-min functional threshold power (FTP) test and complementary assessments (Bosco jump tests, blood pressure, heart rate, lactate, glycaemia, creatine kinase, albuminuria) across three time points (baseline, immediately post-FTP, and 24 h post-FTP). Statistical analyses included t-tests, ANOVA, and Spearman correlations, for recovery dynamics, with significance set at p < 0.05. Results: Professionals exhibited significantly higher FTP (5.5 ± 0.3 vs. 4.3 ± 0.4 W/kg, p < 0.001), greater post-exercise lactate (13.8 ± 1.6 vs. 11.2 ± 1.4 mmol/L, p < 0.01) and higher CK 24-h responses (412 ± 86 vs. 291 ± 74 U/L, p < 0.05). Cardiovascular and metabolic recovery slopes were faster in professionals (p < 0.05). Despite lower baseline jump values, professionals showed reduced neuromuscular fatigue (SJ post/pre = 0.94 ± 0.04 vs. 0.88 ± 0.05, p < 0.05). FTP correlated strongly with 5-min all-out power (r = 0.76, p < 0.01) and Wingate mean power (r = 0.75, p < 0.01). Eight responder profiles emerged across four physiological domains, with professionals predominantly showing multi-domain adaptation patterns. Although additional variables, such as elevated albuminuria and altered Elasticity Index (EI), provide insight into renal and neuromechanical stress responses, they were excluded from the final profiling due to limited practical interpretability. Conclusions: Fatigue and recovery in prolonged cycling show substantial interindividual variability across neuromuscular, metabolic, cardiovascular, and biochemical domains. Professional cyclists display faster recovery and more frequent multidomain responder profiles. The four-variable model (FTP, lactate, CK, SJ post/pre) enables clear identification of physiological responder types and offers a practical, integrative framework for personalised monitoring and performance management.

Background: Inspiratory muscle performance plays a crucial role in athletic demands, yet its associations with anthropometric and positional variables in American football remain underexplored. This study examined relationships between inspiratory metrics and key characteristics in Division I collegiate football players. Methods: Eighty-five Division I collegiate football players (mean academic year in school: 2.87; height: 74.3 inches; weight: 108.13 kg; BMI: 30.21) underwent the Test of Incremental Respiratory Endurance (TIRE) to measure maximal inspiratory pressure (MIP), sustained maximal inspiratory pressure (SMIP), and inspiratory duration (ID). Bivariate and multivariate analyses assessed associations with height, weight, BMI, year in school, offense/defense status, and playing position. Results: Inspiratory performance showed limited associations with anthropometric variables, with only a weak correlation between height and ID. (ρ = 0.243, p = 0.024). No significant differences were observed by year in school or position Conclusions: Inspiratory performance appears largely independent of anthropometric and positional factors; future research should explore targeted respiratory training as a hypothesis rather than a confirmed benefit.

Background: Physiological and psychological factors are important for determining static breath-hold duration. Preconditioning, such as preparatory apneas at functional residual capacity, is a potentially valuable method for prolonging breath-hold duration at total lung capacity. We investigated the physiological influence of preparatory apneas to determine the possible association with maximal apnea duration via diaphragmatic pressure and electromyographic measurements. Methods: Fourteen male breath-hold divers (39 ± 10 years; body mass, 87.2 ± 8.5 kg; body fat, 14.4 ± 3.8%; body height, 186.6 ± 3.9 cm; training experience, 14.2 ± 9.6 years) were included. We measured diaphragm activity during breath-holds via transdiaphragmatic pressure (Pdia) using balloon-tipped catheters in the stomach and esophagus and electromyographic (EMG) activity. From these, ∆EMG and ∆Pdia for every involuntary breathing movement (IBM) during all apneas were quantified. Furthermore, a pressure difference (difference between the first and last IBM Pdia value) and the respiratory neuromuscular output index (RNMI) (∆Pdia/∆EMG) were included as indirect parameters of the pressure perceived. These variables were measured during three preparatory breath-holds (average duration = 185 ± 69 s and range = 62-309 s, separated by 2.5 min) and three maximal breath-holds (average duration = 308 s and range = 179-733 s, separated by 5 min). Results: The preparatory apnea performed at FRC elicited significantly higher Pdia activity (p < 0.00) and a significantly lower RNMI (p = 0.00-0.01) compared to the maximal apneas. Furthermore, a higher and more pronounced increase in Pdia during the preparatory apnea at FRC was related to longer maximal apneas (Max 1, r = 0.65, p = 0.01; Max 2, r = 0.65, p = 0.02; Max 3, r = 0.66, p = 0.01). Conclusions: The results suggest an acute preconditioning effect of primarily the preparatory apnea at FRC on the duration of the subsequent maximal apneas. The implementation of preparatory apneas preceding maximal apneas during training sessions may elicit a longer breath-hold duration in trained divers.

Background: Aging reduces proprioception and neuromuscular control, leading to impaired balance and increased pain, particularly in women aged 65 years and older with knee osteoarthritis (KOA). Therefore, this study investigated the effects of walking exercise using a water inertial load on dynamic balance and pain in this population. Methods: Thirty-four women aged 65 years and older with KOA were recruited and randomly assigned to an experimental group (Aqua Vest group, n = 17) or a control group (weighted vest group, n = 17). After dropout, data from 28 participants were included in the analysis. Both groups performed the same walking exercise program twice weekly for eight weeks. Dynamic balance was evaluated using the Y-Balance Test (YBT), postural control using center of pressure (COP), and pain using the visual analogue scale (VAS). Data were analyzed using an analysis of covariance (ANCOVA) for between-group comparisons and the Wilcoxon signed-rank test for within-group changes. Results: The experimental group showed significantly greater improvement in YBT composite scores compared with the control group (p < 0.05). COP velocity showed a significant improvement in the anterior direction (p < 0.05), whereas no significant differences were observed in other directions. Pain decreased in both groups, but no significant between-group difference was observed. Conclusions: Eight weeks of walking exercise using a water inertial load significantly improved dynamic balance and showed a positive trend toward pain reduction in women aged 65 years and older with KOA. These findings suggest that the nonlinear inertial characteristics of water may enhance sensory-motor integration and postural control, contributing to improved balance performance.

Objectives: This study compared the training effects of two horizontal plyometric training interventions over six weeks on sprint performance and jump kinematics in young female athletes. Methods: Nineteen female football players (age 15.3 ± 0.5 years) were stratified by sprint time into a bounding for speed group (n = 10) or a single leg jumps for speed group (n = 9). All participants completed pre- and post-tests including a 40 m sprint, bounding, and single leg jumps for speed with both legs. Sprint times and velocities over 10 m, 20 m, and maximal speed were recorded, and jump kinematics (horizontal velocity, step length, and step frequency) were analyzed. Results: A significant main effect of time was found for sprint performance, indicating that both groups improved overall. The single-leg jump group showed significant within-group improvements across all sprint measures (10 m, 20 m, maximal velocity, and 40 m time) and significant increases in horizontal velocity and step length during the single-leg jump with both legs. The bounding group showed no significant sprint improvements, with only a within-group increase in step frequency during bounding and a trend toward shorter step length (p = 0.037, ηp² = 0.40). Conclusions: Both training groups improved sprint performance overall, but only the single-leg jump group showed consistent within-group gains in both sprint and jump performance. These findings suggest that single-leg jumps for speed may be a practical and effective option for developing sprint-related qualities in young female football players, although the differences between groups should be interpreted with caution.

Objectives: This study examined the effects of a four-week low-dose mindfulness intervention on ratings of perceived exertion, heart rate, attentional allocation, and performance outcomes, including power output, distance rowed, and strokes per minute, during a rowing task. Methods: Thirty-two participants between 18 and 37 years of age (21.09 ± 3.67) who met the World Health Organization (WHO) physical activity guidelines and had no previous experience with mindfulness or meditation completed a four-week intervention. Participants were either in the mindfulness intervention (n = 17) or the placebo group (n = 15). Participants completed ten visits over four weeks, each consisting of watching an episode of either Headspace Guide to Meditation or Wild Babies on Netflix, followed by a 25 min rowing task. Results: Results indicated no significant group-by-session interaction for any variables. However, a significant main effect for session showed that perceived exertion was significantly lower at the post-assessment compared to the pre-assessment for all participants (p = 0.013, η_p² = 0.19). Additionally, a significant main effect for time revealed a linear increase in perceived exertion across the rowing task (p < 0.001, η_p² = 0.81). Both groups also showed a significant shift from dissociative to associative attention (p < 0.001, η_p² = 0.25). For performance, a significant main effect for session was observed, with greater power output (p = 0.008, η_p² = 0.22) and distance rowed (p = 0.013, η_p² = 0.19) at the post-assessment for both groups. Conclusions: The lack of significant group differences suggests that a low-dose, pre-exercise mindfulness video intervention is likely ineffective for altering psychophysiological responses, indicating that future research should prioritize higher-dosage or real-time guided interventions.

Background: The intravascular laser irradiation of blood (ILIB) is a low-power laser technique that has been studied since the 1970s, and it is associated with the substantial capability to modulate various physiological processes. Indeed, ILIB involves the irradiation of blood with low-intensity light, typically within the red or near-infrared spectrum, to trigger a cascade of photochemical and photobiological events. Objective: This study aimed to analyze previous findings regarding ILIB effects on physical performance. Methods: This study is a narrative review of the literature, addressing the effects of ILIB on multiple organ systems and its impact on physical performance. Results: The most found effects include antioxidant activation, inhibition of inflammatory processes, increased blood fluidity, and improved hemorheological properties. The ILIB affects blood rheological properties based on vasodilatation and decreasing aggregation of thrombocytes. Other effects include improved deformability of erythrocytes, which results in a better supply of oxygen and a decrease in the partial pressure of carbon dioxide. Since ILIB is a photobiomodulation procedure, other applications can be considered, such as ergogenic intervention. In this context, ILIB may favor performance in aerobic exercises and contribute to practices involving anaerobic metabolism by facilitating phosphocreatine resynthesis and ATP restoration. Conclusions: Multiple findings seek to support the potential benefits of ILIB on metabolic and cardiovascular responses associated with exercise training, providing potential improvements in athletic performance.

Background: Accurately tracking body-composition changes in endurance field settings remains methodologically challenging. This study aimed to evaluate whether changes in subcutaneous adipose tissue (SAT) across a 7-day ultramarathon are better reflected by anthropometric indices than by body mass (BM) alone. Methods: Twenty ultrarunners were assessed using both anthropometric indices and ultrasound measurements of SAT thickness, applying a novel method that distinguishes layers including (D_I) versus excluding (D_E) embedded fibrous structures. Measurements were obtained before the race and after Stages 4 and 7. Indices included body mass index (BMI), mass index (MI_I), and waist-to-height ratio (WHtR). Results: Total SAT thickness decreased significantly for both D_I (p = 0.001) and D_E (p < 0.001). BM, BMI, MI_I, and WHtR also declined significantly post-race (p < 0.001). SAT reduction was most pronounced at the abdominal and thigh sites. Additionally, ultrarunners with lower D_E values exhibited lower fat at the abdomen and distal triceps. BMI was significantly related to D_E at the upper and lower abdomen and erector spinae; MI_I was significantly associated with D_E at the upper and lower abdomen; and WHtR correlated with both D_E and D_I at abdominal and erector spinae sites. BM showed no significant association with any SAT parameter. Conclusions: Ultrasound-derived SAT thickness, in combination with BMI, MI_I, and WHtR, offers a field-feasible approach to evaluate body-composition change during multistage ultramarathons. In contrast, BM alone does not reliably reflect SAT distribution or loss.

Background: Despite numerous data on whole-body responses, we have less information about local muscular changes during physical exercise in athletes. Oxygen saturation (SmO₂) changes in the working muscles follow phases of load and are useful, as local metabolism could influence physical fitness. Methods: A total of 100 asymptomatic elite water polo players (63% male, age: 17.2 (interquartile range: 16.1-18.9) years) were examined using near-infrared spectroscopy to measure SmO₂ in both vastus lateralis and left deltoid muscles during continuous uphill running treadmill exercise. Results: Differences were observed between upper and averaged lower limb resting SmO₂ (82.1% (77.0-89.0%) vs. 68.3% (59.2-73.6%), p < 0.001). During exercise, the relative decrease in averaged lower limb SmO₂ was greater compared to the upper limb at the anaerobic threshold (-0.371 (-0.539--0.200) vs. -0.224 (-0.340--0.099), p < 0.001) and at maximal exercise (-0.557 (-0.750--0.411) vs. -0.420 (-0.556--0.271), p < 0.001). Higher averaged lower limb relative SmO₂ was recorded compared to the upper limb after 5 min cool-down (+0.081% (-0.046-+0.195%) vs. -0.047% (-0.140-+0.000), p < 0.001). No differences were found between males and females in resting lower limb SmO₂. Both sexes showed a monotonic decrease in SmO₂ during exercise, with differences in the relative values at the anaerobic threshold and at maximal intensity. Females exhibited a rebound in SmO₂ after a 5 min cool-down. Conclusions: We provide insights into SmO₂ alterations during maximal-intensity exercise and recovery through the measurements of elite water polo athletes, also highlighting sex differences in SmO₂. Measuring local SmO₂ changes is a promising additional method in physical fitness follow-up.