Boysenstefansen3814
at family and social environmental interventions are best undertaken earlier in childhood, particularly among boys.
The purposes of the present study were (1) to determine whether the physical working capacity at the fatigue threshold (PWC
) model that has been used for estimating the onset of neuromuscular fatigue in the vastus lateralis (VL) during incremental treadmill running could also be applied to the vastus medialis (VM), biceps femoris (BF), and semitendinosus (ST) muscles; and (2) if applicable, to compare the running velocities associated with the PWC
among these muscles.
Eleven subjects (age 21.7 ± 1.8 years) performed an incremental treadmill test to exhaustion with electromyographic signals recorded from the VL, VM, BF, and ST.
The results indicated there were no significant (p > 0.05) mean differences in the running velocities associated with the PWC
for the VL (14.4 ± 2.0 km/h), VM (14.3 ± 1.9 km/h), BF (13.8 ± 1.8 km/h), and ST (14.7 ± 2.3 km/h). In addition, there were significant inter-correlations (r = 0.68-0.88) among running velocities associated with the PWC
of each muscle. Individual results also indicated that 9 of the 11 subjects exhibited identical PWC
values for at least 3 of the 4 muscles, but there were no uniform patterns for any intra-individual differences.
The findings of the present study suggested that the PWC
test is a viable method to identify neuromuscular fatigue in the quadriceps and hamstrings during incremental treadmill exercise and results in consistent PWC
values among these muscles.
The findings of the present study suggested that the PWCFT test is a viable method to identify neuromuscular fatigue in the quadriceps and hamstrings during incremental treadmill exercise and results in consistent PWCFT values among these muscles.
This study aimed to assess the effectiveness and time course for improvements in explosive actions through resistance training (RT) vs. plyometric training (PT) in prepubertal soccer players.
Thirty-four male subjects were assigned to a control group (n = 11); an RT group (5 regular soccer training sessions per week, n = 12); a PT group (3 soccer training sessions and 2 RT sessions per week, n = 11). The outcome measures included tests for the assessment of muscle strength (e.g., 1 repetition maximum half-squat test), jump ability (e.g., countermovement jump, squat jump, standing long jump, and multiple 5 bounds test), linear speed (e.g., 20 m sprint test), and change of direction (e.g., Illinois change of direction test).
The RTG showed an improvement in the half-squat (Δ = 13.2%; d = 1.3, p< 0.001) and countermovement jump (Δ = 9.4%; d = 2.4, p< 0.001) at Week 4, whereas improvements in the 20-m sprint (Δ = 4.2%; d = 1.1, p < 0.01); change of direction (CoD) (Δ = 3.8%; d = 2.1, p < 0.01); improvements, which manifested earlier in the RTG than in the PTG. These outcomes may help coaches and fitness trainers set out clear and concise goals of training according to the specific time course of improvement difference between RT and PT on proxies of athletic performance of prepubertal soccer players.
RT and PT conducted in combination with regular soccer training are safe and feasible interventions for prepubertal soccer players. In addition, these interventions were shown to be effective training tools to improve explosive actions with different time courses of improvements, which manifested earlier in the RTG than in the PTG. These outcomes may help coaches and fitness trainers set out clear and concise goals of training according to the specific time course of improvement difference between RT and PT on proxies of athletic performance of prepubertal soccer players.
Most papers examining the lateral abdominal muscles (LAMs) and low back pain (LBP) are cross-sectional, with groups of participants being divided into a control and an LBP group. We hypothesized that morphological measurements of the LAMs in adolescent soccer players may predict future LBP incidence. The aim of this study was to examine the associations between the morphology of LAMs and LBP incidence rate among adolescent soccer players.
Ninety-seven adolescent male soccer players with no LBP at baseline were recruited into the prospective cohort study. The thickness of the LAMs was measured at baseline by ultrasound imaging in a supine rest position. Nine cases of LBP occurred during the follow-up 6-month observation.
An obliquus internus (OI) asymmetry was related to increasing LBP risk (odds ratio = 19.99; 95%CI 2.4-167.9). Spearman correlation also showed a linear relationship between OI asymmetry value and duration of LBP (R = 0.75, p = 0.02). An OI side-to-side difference greater than 1.25 mm suggests possible LBP incidence in the 6-month observation among adolescent soccer players.
The morphological changes of the OI may be related to LBP's incidence in adolescent soccer players. The presence of OI asymmetry increases the odds of LBP by at least 2.4 times. Hypertrophy of the OI on one side of the body may contribute to trunk muscle imbalance.
The morphological changes of the OI may be related to LBP's incidence in adolescent soccer players. The presence of OI asymmetry increases the odds of LBP by at least 2.4 times. Hypertrophy of the OI on one side of the body may contribute to trunk muscle imbalance.
Resistance exercise has numerous, well-documented benefits on the health and functional performance of older adults. However, little information exists on the affective responses to resistance exercise in this population. As affective responses can predict continued exercise behavior, examining if and how they differ between resistance exercise intensities and frequencies in older adults may provide important data to improve resistance exercise prescription.
We monitored the affective responses of older adults when performing high-velocity, low-load (HVLL) or low-velocity, high-load (LVHL) resistance exercise once or twice weekly. A total of 40 moderately to highly active, but resistance-exercise naïve, older adults (60-79 years) completed 1 of 4 randomly assigned progressive resistance exercise conditions HVLL once weekly (HVLL1 n = 10), HVLL twice weekly (HVLL2 n = 10), LVHL once weekly (LVHL1 n = 10), or LVHL twice weekly (LVHL2 n = 10). The Physical Activity Affect Scale, Felt Arousal Scale, Feeling SHowever, the role that supervision and social interaction played in shaping the participants' responses is unclear.
To examine the impact of a 6-week endurance training on red blood cell (RBC) aging and deformability of healthy participants to detect possible improved hemorheological and performance-related adaptations.
A total of 31 participants (17 females and 14 males) performed a 6-week moderate training protocol (three 1-h running sessions per week at 70% of maximal heart rate). Blood was sampled before and after the training. RBCs from each participant were fractioned according to density and age into 4 RBC subfractions. SR-717 solubility dmso Subfractions were examined for changes of RBC properties, including aging distribution, RBC deformability, RBC microparticles, and phosphatidylserine concentrations. RBC and plasma nitrite levels were measured as indicators of nitric oxide metabolism.
Aerobic performance, peak oxygen consumption, ventilatory thresholds, velocity at the aerobic-anaerobic threshold, and lactate at exhaustion improved after training. The relative amount of both young RBCs and old RBCs increased, and the amount of duced, which might support oxygen supply in the microcirculation.
Athletes tend to have better visuo-motor performance than do sedentary individuals. However, several basic visual-function and perceptual parameters remain unexplored to date. In this study, we investigated whether differences exist in visual function, performance, and processing between basketball players and individuals without a sport-involvement background.
A total of 33 healthy men with no visual impairment or pathology were divided into 2 groups, depending on the involvement in sport (semi-professional basketball players and sedentary individuals). We tested their baseline heart-rate variability in the resting position apart from subjective questionnaires to determine their physical fitness level, and we checked their visual function, performance, and processing through an extended battery of optometric tests.
The 2 groups differed in resting heart-rate variability parameters (p < 0.001), confirming their dissimilarities in regular time practising sports per week. The basketball players showed a closer breakpoint and recovery nearpoint of convergence, a higher fusional-vergence rate, better discriminability halos, and better eye-hand coordination (all p values < 0.05).
These results show evidence that athletes, basketball players in this case, exhibit better performance in several visual abilities in comparison to a group of individuals without sporting backgrounds, suggesting an improvement due to the systematic involvement of those skills during basketball practice.
These results show evidence that athletes, basketball players in this case, exhibit better performance in several visual abilities in comparison to a group of individuals without sporting backgrounds, suggesting an improvement due to the systematic involvement of those skills during basketball practice.
Core affect is defined as the most general affective construct consciously accessible that is experienced constantly. It can be experienced as free-floating (mood) or related to prototypical emotional episodes. link2 The aim of this study was to examine the influence of pleasant and unpleasant core affect on cyclo-ergometer endurance performance. Specifically, we considered the influence of pleasant and unpleasant core affect on performance outcomes (i.e., time to task completion) and rate of perceived exertion (RPE; Borg Scale, category ratio-10) collected during the task.
Thirty-one participants aged 20-28 years were recruited. Core affect was randomly elicited by 2 sets of pleasant and unpleasant pictures chosen from the international affective picture system. Pictures were displayed to participants during a cyclo-ergometer performance in 2 days in a counterbalanced order. RPE was collected every minute to detect volunteers' exhaustion.
The study sample was split into 2 groups. Group 1 comprised participannpleasant core affect.
Findings suggest differential effects of pleasant and unpleasant core affect on performance. Moreover, core affect was found to influence perceived exertion and performance according to participants' preferences for pleasant or unpleasant core affect.
Citrulline is one of the non-essential amino acids that is thought to improve exercise performance and reduce post-exercise muscle soreness. link3 We conducted a systematic review and meta-analysis to determine the effect of citrulline supplements on the post-exercise rating of perceived exertion (RPE), muscle soreness, and blood lactate levels.
A random effects model was used to calculate the effect sizes due to the high variability in the study design and study populations of the articles included. A systematic search of PubMed, Web of Science, and ClinicalTrials.gov was performed. Eligibility for study inclusion was limited to studies that were randomized controlled trials involving healthy individuals and that investigated the acute effect of citrulline supplements on RPE, muscle soreness, and blood lactate levels. The supplementation time frame was limited to 2 h before exercise. The types and number of participants, types of exercise tests performed, supplementation protocols for L-citrulline or citrulline malate, and primary (RPE and muscle soreness) and secondary (blood lactate level) study outcomes were extracted from the identified studies.
