Research Quarterly for Exercise and Sport最新文献

Purpose: We examined the movement, physiological and muscle function responses to running with and without (i.e. linear) multiple directional changes to understand which measures of external demands better reflected changes in the internal response. Methods: Twelve team sport athletes completed a linear and multidirectional running trial during which movement characteristics, oxygen consumption ($\dot{V}{O}_2$), blood lactate (B[La]) and heart rate (HR) were measured. Isometric peak torque of knee extensors and flexors was also assessed before and after each trial. Results: High speed running distance was higher during the linear trial (p < 0.001), whereas time at high metabolic power (p = 0.046), number of accelerations (p < 0.001), summated HR (p = 0.003) and B[La] (p = 0.002) were higher during the multidirectional trial. Integrated external to internal ratios of high-speed running: summated HR and high-speed running: total $\dot{V}{O}_2$ were different between multidirectional and linear trials (p ≤ 0.001). Conversely, high metabolic power: summated HR and high metabolic power: total $\dot{V}{O}_2$ were similar (p ≥ 0.246). Small decrements in knee flexor (p = 0.003) and extensor torque (p = 0.004) were observed after both trials. Conclusion: Time at high metabolic power better reflects the increased internal response during running with more directional changes than high speed running.

Purpose: Physical inactivity is linked with several chronic diseases and poor academic outcomes. This study aimed to examine the effect an under-the-desk band would have on middle school students' physical activity level, and academic engagement. Methods: Two local middle school classrooms (n = 42, M = 20, F = 22) participated in the study, which was conducted over 14 weeks. Physical activity was measured with accelerometry, and academic engagement was assessed using momentary time sampling. Enrolled participants were provided an accelerometer to wear upon entering the classroom. The baseline period lasted for 36 days. During the intervention period, which lasted for the next 30 days, an under-the-desk band was provided to students to freely fidget at their desks. After the study, 13 participants (M = 5, F = 8) in Class A were included in final physical activity analysis, and the 6 participants (M = 3, F = 3) in Class B were included in the academic engagement analysis. Results: Class A had significant increases in percentage of sedentary time (MD = -12.91%, ES = .88) in addition to significant decreases in the percentage of light (MD = 8.82%, ES = .67), moderate (MD = 3.08%, ES = .84), and vigorous (MD = -.04%, ES = .63) physical activity time during the intervention period compared to the baseline period. No significant or meaningful changes occurred in academic engagement with the use of the under-the-desk band. Conclusions: This study high- lights the importance of finding appropriate methods to increase physical activity for adolescents.

Objective: The purpose of this study was to examine the reliability and validity of the 30-15 Intermittent Field Test (30-15_IFT) with and without a ball. Methods: Twenty-four collegiate female soccer players (19.46 ± 1.22 years; 167.01 ± 7.23 cm; 60.95 ± 7.84 kg) performed 1 trial of the Yo-Yo Intermittent Recovery (YYIR) test, 3 trials of the 30-15_IFT, and 3 trials of the 30-15_IFT with a ball (30-15_IFT-B), separated by a minimum 48 hours. Maximal intermittent running velocity (V_IFT), heart rate at exhaustion (HR_peak), and rating of perceived exertion (RPE) were collected. Results: Intraclass correlation coefficients (ICCs) between trials demonstrated good reliability during the 30-15_IFT in V_IFT (ICC = 0.88) and HR_peak (ICC = 0.89), in addition to the 30-15_IFT-B V_IFT (ICC = 0.83) and HR_peak (ICC = 0.87). V_IFT was significantly reduced in 30-15_IFT-B (15.82 km h^-1) compared to 30-15_IFT (17.52 km h^-1; p < .001), regardless of trial. HR and RPE were significantly greater in 30-15_IFT compared to 30-15_IFT-B (p < .05). Estimated maximal oxygen consumption (VO₂max) YYIR and estimated VO₂max of 30-15_IFT and 30-15_IFT-B was very strongly (r = 0.82) and strongly (r = 0.68) correlated. Conclusion: The 30-15_IFT is considered valid and reliable and the 30-15_IFT-B was reliable in female soccer players.

Public health guidelines for resistance training emphasize a minimal effective dose intending for individuals to engage in these behaviors long term. However, few studies have adequately examined the longitudinal time-course of strength adaptations to resistance training. Purpose: The aim of this study was to examine the time-course of strength development from minimal-dose resistance training in a large sample through retrospective training records from a private international exercise company. Methods: Data were available for analysis from 14,690 participants (60% female; aged 48 ± 11 years) having undergone minimal-dose resistance training (1x/week, single sets to momentary failure of six exercises) up to 352 weeks (~6.8 years) in length. Linear-log growth models examined strength development over time allowing random intercepts and slopes by participant. Results: All models demonstrated a robust linear-log relationship with the first derivatives (i.e., changes in strength with time) trending asymptotically such that by ~1-2 years strength had practically reached a "plateau." Sex, bodyweight, and age had minimal interaction effects. However, substantial strength gains were apparent; approximately ~30-50% gains over the first year reaching ~50-60% of baseline 6 years later. Conclusion: It is unclear if the "plateau" can be overcome through alternative approaches, or whether over the long-term strength gains differ. Considering this, our results support public health recommendations for minimal-dose resistance training for strength adaptations in adults.

Purpose: With the increased access to neural networks trained to estimate body segments from images and videos, this study assessed the validity of some of these networks in enabling the assessment of body position on the bicycle. Methods: Fourteen cyclists pedaled stationarily in one session on their own bicycles while video was recorded from their sagittal plane. Reflective markers attached to key bony landmarks were used to manually digitize joint angles at two positions of the crank (3 o'clock and 6 o'clock) extracted from the videos (Reference method). These angles were compared to measurements taken from videos generated by two deep learning-based approaches designed to automatically estimate human joints (Microsoft Research Asia-MSRA and OpenPose). Results: Mean bias for OpenPose ranged between 0.03° and 1.81°, while the MSRA method presented errors between 2.29° and 12.15°. Correlation coefficients were stronger for OpenPose than for the MSRA method in relation to the Reference method for the torso (r = 0.94 vs. 0.92), hip (r = 0.69 vs. 0.60), knee (r = 0.80 vs. 0.71), and ankle (r = 0.23 vs. 0.20). Conclusion: OpenPose presented better accuracy than the MSRA method in determining body position on the bicycle, but both methods seem comparable in assessing implications from changes in bicycle configuration.

Previous school-based high-intensity interval training (HIIT) interventions have focused on the quantity of physical activity (PA) achieved during physical education (PE) rather than students' PE experiences, including enjoyment. Purpose: To evaluate the feasibility of a fitness- and skill based HIIT intervention guided by the Self Determination Theory. Method: For this pretest-posttest randomized controlled 6-week pilot study, 4-5^th grade students (15 boys, 30 girls; age = 10.5 ± 0.9 years) completed a 16-19-minute HIIT circuit (INT); whereas, 22 students (10 boys, 12 girls; age = 10.5 ± 0.9 years) engaged in regular PE (CON). Two-way mixed ANCOVA tests were performed to assess preliminary efficacy. Results: Participants reported favorable program satisfaction (mean 3.6 ± 1.5 out of 5). The physical educator reported a high feasibility survey score (31/35), and themes emerging from a program acceptability interview included positive perceptions of the HIIT program and strategies for future implementation. A large effect size was evident for cardiorespiratory fitness (ηp² = 0.26), as VO_2peak increased in INT from 53.6 ± 6.1 to 56.9 ± 7.3 ml/kg/min and decreased in CON (53.9 ± 7.0 to 52.4 ± 10.4 ml/kg/min). Students in INT exhibited greater amounts of moderate-to-vigorous PA and vigorous PA during PE versus CON, based on accelerometer data (23.4 ± 5.0 vs. 15.7 ± 4.7 min/hr, ηp² = 0.45; 4.5 ± 2.6 vs. 2.3 ± 1.3 min/hr; ηp² = 0.27, respectively). Conclusions: Findings support the feasibility of this fitness- and skill-based HIIT program and may be a valuable addition to elementary school PE programs.

Purpose: This study examined the effects of coordinative exercise on children's sustained attention and perceptual discrimination in a school-based physical education (SBPE) setting. Methods: Seventy-three children received an intervention of moderate-to-vigorous intensity coordinative exercise, and 75 children participated in a moderate-to-vigorous intensity physical activity as part of a regular physical education class. Two neuropsychological tests of executive function (EF) were used to assess attention and perceptual discrimination functions before and after each treatment. Results: The results found that coordinative exercise significantly improved the performances on sustained attention and perceptual discrimination, as evidenced by enhanced response accuracy and improved speed of responding. Specifically, higher progressions in task performance were seen following coordinative exercise relative to regular physical activity. Conclusion: These findings suggest that coordinative exercise could enable more robust improvements in sustained attention and perceptual discrimination among children. Overall, we conclude that structured coordinative exercise, implemented in SBPE settings, may be a promising alternative to promote children's cognitive abilities.

Purpose: This study compared physiological and perceptual variables between short and long durations of rowing-based high intensity interval exercise (HIIE). Methods: Fourteen active adults (age = 26.4 ± 7.2 yr) performed incremental rowing exercise to fatigue to measure maximal oxygen uptake (VO₂max) and peak power output (PPO). The subsequent 20 min sessions required HIIE (eight 60 s efforts at 85%PPO with 90 s of active recovery at 20%PPO or 24 20 s efforts at 85%PPO with 30 s of active recovery at 20%PPO) or moderate intensity continuous exercise (MICE) at 40%PPO. During exercise, VO₂, heart rate (HR), blood lactate concentration (BLa), rating of perceived exertion (RPE), and affective valence were measured. Results: Data show significantly (p < 0.001) higher peak VO₂ (84 ± 7 vs. 76 ± 5%VO₂peak, d = 0.99), peak HR (94 ± 4%HRpeak vs. 90 ± 4%HRpeak, d = 1.12), BLa (7.0 ± 2.5 mM vs. 4.1 ± 1.0 mM, d = 1.22), end-exercise RPE (12.8 ± 2.0 vs. 11.0 ± 1.7, d = 1.29), and lower affective valence (2.1 ± 1.6 vs. 2.9 ± 1.2, d = 0.61) with long versus short HIIE. Time spent above 85%HRpeak was significantly higher (p < 0.001) in short versus long HIIE (606 ± 259 vs. 448 ± 26 s, d = 0.91). Conclusion: Longer rowing-based intervals elicit greater cardiometabolic and perceptual strain versus shorter efforts, making the latter preferable to optimize perceptual responses to HIIE.

Physical Education Teacher Education (PETE) training has the potential to influence graduates' decisions as physical educators. Utilizing themes from Rogers' Diffusion of Innovations and Lawson's Occupational Socialization theories, we focused on graduates from a single PETE program which, beginning in 2007, began integrating content, expectations, and experiences relating to an expanded role of the physical educator such as in comprehensive school physical activity programs (CSPAPs). Purpose: The purpose of this study was to examine transfer in terms of university training leading to teaching practices in expanded physical activity programming. Method: An electronic questionnaire was sent to 335 graduates from May 2000 through May 2019. Sixty-seven graduates' questionnaires were investigated looking at perceptions of CSPAP as an innovation, current expanded physical activity (PA) offerings, and memories of PETE. Additionally, 13 participants participated in a school visit and interview which acted as a fidelity check for self-reported levels of expanded PA programming reported in the questionnaire. Results: All 67 graduates included some amount of expanded PA programming. Positive correlations were found with perception of CSPAP as an innovation, for both year of graduation and memory of PETE programming, thus students exposed to CSPAP programming during PETE were implementing components at their schools at higher levels. Conclusion: There is positive potential for professional socialization to influence graduates' practices. Perceptions of CSPAP as an innovation were positive and support the promotion of triability and starting small when PETE programs encourage expanded PA programming.

Purpose: This study compared physical self-concept and subjective vitality of police, physical education, and psychology students. Moreover, the study investigated whether students who reported a higher level of physical activity differently rated physical self-concept and subjective vitality and whether physical activity was associated with subjective vitality. Methods: The study sample included 422 university students (249 females) from three state academic institutions: University of Criminal Investigation and Police Studies (n = 165), Faculty of Sport and Physical Education (n = 156) and Faculty of Psychology (n = 101). The mean age was 20.85 ± 3.59 years. They completed a physical self-description questionnaire, the subjective vitality scale, and a physical activity questionnaire using the Survey Monkey platform. Multivariate analysis of variance investigated the differences in physical activity, physical self and vitality, while regression analysis investigated the association of physical self and physical activity with subjective vitality. Results: Police students and physical education students reported higher levels of physical activity and perceived higher their own physical self and subjective vitality than psychology students. From the whole sample, students who were sufficiently physically active also scored higher on physical self-concept and subjective vitality. There was a significant association of physical activity level with subjective vitality. Conclusion: Physical activity was directly associated with students' subjective evaluation of their own health. It can be concluded that students should aim to attain a minimum of 150 min per week of physical activity. Students and faculties should be involved in the attainment of minimal levels of physical activity. This could improve students' subjective perception of self, along with objective measures of health and wellbeing.