International journal of exercise science最新文献

Blood flow restriction (BFR) combined with exercise has been shown to enhance muscle hypertrophy, strength, and aerobic capacity. While previous studies have evaluated the use of BFR among various practitioners, none have investigated its use exclusively among licensed U.S. physical therapists (PTs). A cross-sectional survey was distributed electronically to licensed U.S. PTs. Participants were required to use BFR currently in clinical practice. Survey items included respondents' demographics, practice setting, exercise mode, the type of BFR equipment used, and adverse events. A total of 134 licensed PTs from 20 states completed the survey. BFR was most commonly used in outpatient orthopedic settings, primarily in conjunction with resistance exercises. The Delfi unit was the most frequently used device (64%). No major adverse effects reported (e.g., thrombosis, rhabdomyolysis, nerve damage). Minor adverse effects, including dizziness, numbness, nausea, and delayed onset muscle soreness, were reported by 8% of participants (n = 11). This survey found no major adverse effects and a low prevalence of minor, transient adverse effects. These findings are consistent with previous BFR safety literature and provide a foundational overview of BFR practices among U.S. PTs.

This longitudinal study explored entry route- and age-related fitness differences between cadet (CR) and general population (GR) firefighter recruits. Fitness data were collected from eight separate firefighter recruit academy cohorts (N = 317; 122 CR, 195 GR; 27.17 ± 7.58 yrs, 177.30 ± 8.72 cm, 88.65 ± 17.78 kg). In the first week of the academy, recruits completed an assessment battery including: body composition via skinfold measures to estimate body fat (BF, %) and fat-free mass (FFM, kg); aerobic fitness (VO_2peak, mL· kg^-1· min^-1) and heart rate recovery (HRR_1min, %) estimated from the five-minute Forestry Step Test; movement quality via a squat-based movement screen (MES, 0-100); muscular strength via the sum of right and left handgrip (SHG, kg); and muscular endurance via a two-minute push-up test. Due to non-normally distributed data, non-parametric statistical tests were used. Wilcoxon rank-sum tests (α < 0.05) evaluated fitness differences between entry routes. Kruskal-Wallis tests evaluated differences between four age groups: A1 (19-21 yrs), A2 (22-29 yrs), A3 (30-39 yrs), and A4 (40+ yrs). CR had significantly (p < 0.05) lower age, BM, BF, and FFM, but greater MES, VO_2peak, HRR_1min, and PU. A1 had lower BM, BF, and FFM; and greater VO_2peak, HRR_1min, and PU (p < 0.01) than all other ages. The range of fitness in recruits upon academy entry necessitates careful programming to support optimization of fitness in all recruits, regardless of age. The fitness elements of an academy may present opportunities to build health and fitness literacy, necessary for career longevity.

The intensity of aerobic exercise is influenced by maximum heart rate (MHR), which can be assessed through an incremental exercise test. However, this method requires specialized equipment and a level of fitness that individuals who are sedentary or overweight may lack. Therefore, estimating MHR using formulas is essential. Various methods exist to calculate MHR, but their effectiveness in real exercise programs for obese individuals remains unclear. This study aimed to investigate the effects of aerobic exercise using different intensity calculation methods, specifically comparing Fox's and Tanaka's maximum heart rate (MHR) equations, as well as the Percentage and Karvonen methods for target heart rate (THR). Seventy-eight men aged 20 to 30 with a body fat percentage of over 20% were divided into one control group and four aerobic exercise groups. EG1 and EG3 used Fox's and Tanaka's equations for MHR and THR from the percentage, while EG2 and EG4 applied the Karvonen method for THR. Participants engaged in 45 minutes of moderate-intensity walking or running on a treadmill four days a week for 12 weeks. Body weight, body fat percentage, BMI, resting heart rate (RHR), and VO₂ max were measured at baseline and after the intervention. After 12 weeks, all exercise groups demonstrated significant improvements in VO₂ max, as well as reductions in body weight, body fat percentage, BMI, and resting heart rate (RHR), whereas the control group showed no changes. No significant differences were found among the exercise groups. Aerobic exercise at various intensities effectively enhances cardiovascular fitness and body composition in obese individuals, indicating that these methods are equally beneficial.

The objective was to investigate screen time (ST) and objectively measured sleep quality in college students. Participants were undergraduate students attending a large metropolitan public university in the southeastern U.S. Participants wore accelerometers on their wrist for 24hr/day for 14 days to capture sleep outcomes, and completed a survey reporting ST duration. Analyses explored weight-status, race/ethnicity, and sleep patterns (presence of daytime sleep) differences among students. Participants (n=29, 86% female, ~21.5 years old, 38% White, 35% Overweight/Obese) slept for an average of 433.8 minutes/night, reported 419.1 minutes of daily ST, and 112 minutes of ST after 10:00PM. College students with daytime sleep (i.e., napping) reported approximately -92 minutes less of daily ST than peers (p=0.04; effect size=0.86). Further studies in larger, diverse samples are needed to explore ST and sleep, specifically the causal relationship and its potential to impact the health of college students at greatest risk of poor health outcomes.

Motion analysis is used to measure proper bicycle fit, avoid injury, and improve cycling performance. Small changes in position can impact joint kinematics and risk for overuse injury. Concerns regarding the often-used biomechanical model Plug-in-Gait (PIG) resulted in the creation of Conventional Gait Model 2 (CGM2). This study aims to compare kinematic outputs of these two models for cycling biomechanics plus between-day reliability of each model. Thirty-five participants participated in two experimental sessions. PiG and CGM2 marker sets were applied, and data was collected while cycling between 80-90 rpm. Model outputs were compared using session one kinematic data. Reliability tests used session one and session two data. Differences in kinematics were found between models for hip flexion (CGM2 - PiG mean difference = -8.2° ± 5.2°, p < .001), hip frontal plane (mean = 5.4 ± 4.1°, p < .001), hip transverse plane (mean = -5.3° ± 11.6°, p = .011), knee extension (mean = 1.8° ± 4.2°, p = .015), knee frontal plane (mean = -10.8° ± 9.6°, p < .001), dorsiflexion (mean = -1.7° ± 3.6°, p = 0.005), and plantarflexion (mean = 3.3° ± 5.4°, p < 0.001). CGM2 ICCs were good-to-excellent (> 0.75) for all motions except frontal plane knee motion. PiG ICCs were > 0.75 only for ankle dorsiflexion and plantarflexion. If CGM2 is used to assess bicycle fit, reference values should be adjusted based on the difference between models to ensure an appropriate fit is obtained. CGM2 has better between-day reliability, therefore practitioners may consider using CGM2 for serial fit sessions.

Accurate physical activity (PA) measurement is crucial for public health surveillance. While self-report questionnaires are commonly used, they have limitations, especially in young children. An affordable and user-friendly device like Feelfit® offers a promising alternative particularly for countries with limited research resources. This study aimed to evaluate Feelfit®'s performance against the widely used ActiGraph® accelerometer in measuring PA among children. A quasi-experimental design was applied. Thirty-nine children (19 boys; 20 girls; aged 11.4 ± 0.5 years) wore both Feelfit® and ActiGraph® during sequentially specified activities of varying intensity ranging from sedentary to vigorous. Data were analysed using paired t-tests, Bland-Altman plots, and intra-class correlation coefficients (ICCs) to assess agreement, precision, and reliability. Feelfit® showed good agreement with ActiGraph® for moderate-to-vigorous PA (MVPA) but overestimated sedentary time and underestimated light PA. It demonstrated better precision for MVPA but low reliability for light PA. Intra-class correlation coefficients were moderate for MVPA (ICC = 0.43), but poor for sedentary time (ICC = 0.11). Feelfit® is a suitable option for measuring MVPA in children, offering acceptable validity and reliability compared to ActiGraph®. However, improvements are needed for accurate measure of sedentary and light activities. Despite these limitations, Feelfit®'s affordability and ease of use make it a valuable tool for use in small- to large-scale research and in resource-limited settings.

Although acutely donning compression garments improves several markers of athletic performance, the effects of training in compression garments remains largely unexplored. Thus, this study aimed to determine the effects of exercise training while donning a novel full-body compression garment on multiple measures of anaerobic performance. Sixteen sedentary males (age: 21±3 y; BMI: 25±3 kg/m²) completed 4 weeks of training with (CG; n=8) or without (CON; n=8) a novel full-body compression garment. Subjects performed a 40m sprint (time and velocity), a 5-repetition maximum barbell back squat (barbell weight and serratus anterior activity), a countermovement vertical jump (VJ; displacement, force, power, velocity, and acceleration), and a Wingate Anaerobic Test (WAnT; peak power, mean power, and fatigue index) before (PRE) and after (POST) training. Data are presented as mean ± SD changes from PRE and were analyzed via two-way repeated measures ANOVAs. CG showed a significant increase when compared to CON for the change in sprint velocity (-0.68±0.26 m/s, P = 0.014), VJ velocity (+0.15±0.07 m/s, P = 0.033), WAnT relative peak power (+0.88±0.49 W/kg P = 0.018), WAnT absolute mean power (+62.37±52.11 W, P = 0.006), and WAnT relative mean power (+0.83±0.53 W/kg, P = 0.004). While there were statistically significant improvements from PRE to POST in other measures, only the aforementioned five variables demonstrated intergroup significance. Overall, donning this novel full-body compression garment during training led to enhanced performance in specific anaerobic measures when compared to not training in the garment.

We hypothesized that an increase in nonexercise physical activity (NEPA), assessed by daily steps outside of steps accrued during supervised exercise training sessions, would be positively correlated with the change in VO_2max. Females ages 18-45 yr (n = 44; 30 ± 7 yr; 67.7 ± 18.3 kg; 24.9 ± 6.4 kg/m²) completed 36 supervised training sessions on a motorized treadmill (3 sessions/week, 30 min/session) over 12 weeks, at 70% VO_2max (80% max heart rate). VO_2max was assessed at baseline, 4, 8, and 12 weeks, and steps outside of the supervised exercise sessions were recorded daily during each week of training with a hip-worn pedometer. For each participant, linear regression was used to determine the slope of steps/day during the 12 weeks of training. Mean VO_2max increased by 8.2% (30.5 ± 5.9 ml/kg/min to 33.0 ± 5.9 ml/kg/min; range -2.65 ml/kg/min to +6.24 ml/kg/min; P < 0.001). Although mean (± Standard Deviation) steps/day did not change during the 12-week intervention, 25 participants decreased daily steps (-1624 ± 1210) and 19 participants increased daily steps (+1713 ± 1402). The change in VO_2max was not different between the two groups (P = 0.74), and the correlation between Δ VO_2max and the slope of the regression (steps/day) over the 12 weeks was not significant (R² = 0.0005; P = 0.88 for ml/kg/min; R² = 0.008, P = 0.59 for l/min). Change in NEPA, assessed by daily steps, does not impact the VO_2max adaptation observed during a vigorous-intensity walking exercise program in females ages 18-45 yr.

Osteoarthritis (OA) is a highly prevalent musculoskeletal condition. It is reported that knee OA progressively affects lower-extremity functioning. Evidence is lacking on when there is a substantial decline in function and whether this trend differs between males and females and disease severity. This study aimed to examine influence of gender and increasing grade of knee OA on lower-extremity function. Following Institutional Ethical Committee approval and signed-informed consent, 115 participants (57-males, 58-females), aged 40-65 years, with diagnosed knee OA (grade 1-4) were recruited. Lower-extremity function was studied using reliable and valid outcome variables such as muscle strength-endurance, joint motion, ground-level activity exposure and physical activity. The medial knee joint space width (JSW) decreased by 56.7%(males) and 49.2%(females) from grades 1 to 2 and by 29.6%(males) and 47.8%(females) from grades 3 to 4. Lower-extremity muscle strength and mobility measured by 30-second-deep-squat test declined by 62%(males) and 40.4%(females) from grades 1 to 2 and by 94.4%(males) and 60.9%(females) from grades 3 to 4. Lower-extremity muscle endurance measured by 30-second-chair-sit-to-stand test declined by 8.3%(males) and 7.1%(females) from grades 1 to 2 and by 31.6%(males) and 85.7%(females) from grades 3 to 4. Physical function decreased by 0.3%(males) and 2.3%(females) from grades 1 to 2 and by 22.7%(males) and 32.0%(females) from grades 3 to 4. Physical activity decreased by 27.6%(males) and 28.6%(females) from grades 1 to 2 and by 53.1%(males) and 60.7%(females) from grades 3 to 4. A substantial decline was observed from grades 3 to 4, when both males and females presented considerable reductions in lower-extremity function.

The Biddle Physical Ability Test (BPAT) is a job task simulation that must be completed in ≤9:34 min:s by structural firefighter candidates to be accepted to a fire training academy. This study investigated the influence of prior attempts on BPAT time. Retrospective analysis was conducted on 1435 male and 72 female candidates. All participants received equivalent instruction on how to complete the BPAT which incorporated: dry hose drag; charged hose drag; halyard raise; roof walk; attic crawl; roof ventilation; victim removal; ladder removal and carry; stair climb with hose bundle; crawling search; stair climb with air bottles; and hose hoist. Candidates in the dataset were split into 1st, 2nd, 3rd, 4th, 5th, and ≥6th attempt groups. A one-way ANOVA, with Bonferroni post hoc, compared groups in BPAT time (all times combined and passing times only; p≤0.05). All candidates who failed to meet time requirements, did not finish, or were disqualified, were recorded. The 1st, 2nd, and 3rd attempt groups were significantly (p≤0.007) slower than the 4th, 5th, and ≥6th attempt groups when considering all and passing times. The percentage of candidates that did not pass the BPAT relative to their attempt group was: 1st = 13%; 2nd = 6%; 3rd = 7%; 4th = 2%; 5th = 0%; ≥6th = <1%. Most candidates passed the BPAT. However, BPAT practice based on previous attempts generally led to faster times and more candidates passing. It could be beneficial for candidates to attend practice courses and fitness training sessions to improve BPAT performance.