Research Quarterly for Exercise and Sport最新文献

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.

Purpose: Recovery-interval strategies may influence physiological and psychological responses during highintensity interval resistance training (HIIRT). This study compared the intensity, performance, and psychological outcomes during all-out effort HIIRT performed with fixed (FRI) and self-selected (SSRI) recovery intervals. Methods: Sixteen trained males (27.2 ± 4.1 years; 84.5 ± 8.9 kg; 55.8 ± 7.1 mL.kg-1.min-1) performed HIIRT bouts interspersed with FRI (10 s) and SSRI (15.3 ± 7.9 s). Results: Relative heart rate (%HRmax) and oxygen uptake (%VO2Peak), number of repetitions, and psychological responses (affection: Feeling ScaleFS; Felt Arousal ScaleFAS; enjoyment: Physical Activity Enjoyment ScalePACES) were assessed. FRI and SSRI elicited similar relative average intensity (p > .05) (%HRmax: 88.1 ± 3.5% vs. 87.6 ± 3.0%; %VO2Peak: 55.3 ± 7.4% vs. 54.1 ± 8.1%, respectively). The number of repetitions similarly decreased in SSRI and FRI from rounds 1 to 4 (~15%; p < .006), with no difference of total volume across conditions (FRI: 358.6 ± 32 reps vs. SSRI:357.5 ± 28.2; p = .89). In each round, no difference between FRI and SSRI (p > .05) was found for FS (3- to 3.5 vs. 2- to 4, respectively) or FAS (2- to 4 vs. 2- to 4, respectively), while PACES was lower in FRI than SSRI (102.8 ± 15.8 vs. 109.2 ± 13.2; p = .04). Conclusion: In conclusion, relative intensity, total repetitions, and affective perception were not influenced by the strategy of recovery intervals. On the other hand, overall enjoyment was favored in SSRI vs. FRI.

Purpose: The preparation of Chinese physical education teachers focuses strongly on movement competence and the development of knowledge about rules and techniques. What is missing are experiences that promote expertise in task design and progressions. The purpose of this study was to examine if participation in classes following the Sport Education model could enhance content expertise by placing students in situations where they were responsible for these tasks. Methods: One hundred and ten physical education majors from a university in central China participated in a semester-long course of volleyball taught using either Traditional Instruction or Sport Education. Pre- and post-course measures were recorded of participants' game performance, common content knowledge (CCK), and specialized content knowledge (SCK). Results: After controlling for pre-intervention scores, statistically significant differences were evident in the posttest scores between the instructional groups for all three measures. The binomial logistic regression model to ascertain the effect of course type on the likelihood that students would reach the benchmark depth of SCK produced statistical significance. Students in the Sport Education classes had 6.67 times higher odds to reach the benchmark than students in the Traditional Instruction classes. Conclusion: The accountability mechanisms specific to Sport Education that have been shown to enhance student motivation and promote knowledge and performance seemed to carry over into this setting. As students in Sport Education were responsible for designing much of their team training, this served to promote their ability to design and sequence tasks based on their team's needs. Implications for physical education teacher education are discussed.

Purpose: Heart rate variability (HRV) has gained acceptance as a key marker of cardiovascular health. We compared HRV responses after continuous moderate-intensity exercise (CMIE) and high-intensity interval exercise (HIIE) matched for intensity and duration in individuals with midspectrum chronic kidney disease (CKD). Methods: Twenty men and women (age 62.0 ± 10 yrs.) diagnosed with CKD stages G3a and G3b participated in a 2 (condition) x 4 (time point) repeated cross-over measures design study. HRV time-domain indices were based on the standard deviation of all NN intervals (SDNN) and the square root of the mean of the sum of the squares of differences between adjacent NN intervals (RMSSD) and frequency domain. High-frequency (HF), low-frequency (LF), total power (TP) were examined. CMIE consisted of treadmill walking for 30 minutes at a 2% incline and speed corresponding to 60%-65% of reserve volume of oxygen (VO₂R). HIIE included five intervals of 3 minutes at 90% of VO₂R and 2 minutes at 20% VO₂R intervals. Conditions were designed to be of the same average intensity (60% to 65% of VO₂R) and caloric expenditure (~144 kcal). Results: Immediately following exercise SDNN, RMSSD, HF, LF, and TP were significantly lower compared to before exercise (p <.05). HRV responses were not different between conditions and conditions X time (p >.05). Conclusions: Thirty minutes of either CMIE or HIIE decreased HRV indices, pointing to an autonomic imbalance favoring vagal mediation. HRV's responses regarding HIIE were no different from CMIE, therefore, from an autonomic function point of view this similarity may be useful for CKD exercise prescription and programming.

Purpose: Morning priming exercise and caffeine intake have been previously suggested as an effective strategy to increase within-day performance and readiness. However, the concurrent effect of both strategies is unknown. The present research aimed to map the within-day time course of recovery and performance of countermovement jump (CMJ) outcomes, kinetics, and strategy and readiness after priming alone and in combination with caffeine. Methods: Eleven participants performed a control, a priming exercise (Priming) and a priming with concurrent caffeine intake (PrimingCaf) in a double-blind randomized, crossover design. CMJ metrics were assessed before, post, and 2 h, 4 h, and 6 h after each condition while readiness was assessed at 6 h. Results: Perceived physical, mental performance capability and activation balance were higher at 6 h after Priming and PrimingCaf conditions. Immediate reductions in jump height (5.45 to 6.25%; p < .046), concentric peak velocity (2.40 to 2.59%; p < .041) and reactive strength index-modified (RSImod) (9.06 to 9.23% p < .051) after Priming and PrimingCaf were observed, being recovered at 2 h (p > .99). Concentric impulse was restored in PrimingCaf (p > .754; d = -0.03 to-0.08) despite lower concentric mean force/BM (p < .662; d = -0.18 to -0.26) as concentric duration was increased (p > .513; d = 0.15 to 0.21). Individual analysis revealed that some participants benefit from both strategies as they showed increases in jump height over the smallest worthwhile change while others did not. Conclusions: Psychological readiness was increased after both priming conditions at 6 h; however, it seems necessary to consider individual changes to achieve the positive effects of the priming or the priming in combination with caffeine on jumping outcomes.

Background: Thigh muscle strength capacities are major modifiable risk factors for knee and thigh muscle injuries. Therefore, their valid assessment is essential. Most isokinetic knee tests are conducted in a seated position and rely on dynamometer-based data. However, their accuracy is doubtful because axis alignment is erroneous. Purpose: This study investigated if hip angle (flexed vs. extended) and assessment method (dynamometer-based vs. camera-based) affect isokinetic outcome parameters. Methods: Sixteen healthy male participants (27 years, 184 cm, 80 kg) performed discrete isokinetic tests of the knee flexors and extensors (60°/s) while their kinematics were captured (100 fps). Results: Both assessment methods revealed very strong linear relationships (94% ≤ R² ≤ 98%) although peak moments (d ≤ 0.87), contractional work (d ≤ 1.26), and functional knee flexor:extensor ratios (d ≤ 0.81) significantly differed. Seated knee flexor tests demonstrated the largest knee trajectory center's misalignment (x = 4.0 cm, z = -2.5 cm; 1.37 ≤ d ≤ 4.74). Conclusion: Hip-angle induced kinematic changes did not affect the relation between the lever arms, thus causing highly proportional deviations of kinetic parameters. The assessment method altered the magnitude, but not the message of isokinetic knee tests, which should be preferentially performed with extended hip joint to improve axis alignment. Knowledge of these kinetic and kinematic interactions assists practitioners and scientists with isokinetic tests and/or rehabilitation training to ensure reasonable interpretations of gathered isokinetic outcomes.

Purpose: The purpose of this study was to explore how parent involvement influenced the effectiveness of a movement intervention targeting gross motor skills and physical activity behavior in preschool-aged boys and girls. Methods: Parents received training at monthly school-based sessions and online to implement the movement intervention once per month at school and once per week at home across 6 months (N = 104; M_age = 48.30 months, SD = 6.90). Children completed the Test of Gross Motor Development-3 at baseline and wore physical activity trackers 24/7 for six weeks during the intervention. COVID-19 disrupted the intervention and prevented immediate post testing. Children (N = 60; M_age = 60.86 months, SD = 6.57) who returned to the center one year later completed gross motor skill retention testing. Results: For each additional school-based session attended by the parents (up to six), children's locomotor and manipulative skills were 1.87 and 1.95 points higher, respectively, at the start of the following academic year. For physical activity, each session increase in attendance at the school-based component of the intervention resulted in an additional 1455 steps in average weekly step count. Conclusion: Increased parent engagement demonstrated greater change in gross motor skills and larger acute physical activity responses. Understanding barriers that impact the level of parental intervention engagement (i.e., dose) also provides insight into why some children learn and others do not within a parent-led intervention. Although the implementation and results of this study were impacted by COVID, these data can help researchers optimize future intervention strategies.

Introduction: The aim of this study was to examine differences between a control warm-up and an Electric Muscle Stimulation (EMS)-induced warm-up in off-road cyclists when examining anaerobic performance measures from a repeated Wingate test (WAnT). Methods: Twelve trained off-road cyclists completed a randomized crossover study (age: 31 ± 10 years, height: 176.79 ± 6.09 cm, body mass: 74.57 ± 4.77 kg). Participants completed two randomized, separate testing sessions involving a control warm-up and an EMS warm-up before undergoing the repeated WAnT, which was used to collect anaerobic performance and physiolo- gical measures during both sessions. High-frequency EMS was applied to the knee extensor muscles for 4 min after a standardized warm-up during the EMS session. Results: Analysis revealed that there were no significant differences between mean power output, peak power output, and percentage decrement between the two sessions. The EMS session resulted in significantly lower average HR values and significantly lower differences in pre-to-post-test blood lactate values when compared to the control session. Discussion: According to the results of this study, an acute application of EMS is not a useful tool for off-road cyclists to improve power output or maintain anaerobic capacity. Hence, its use before competition is questionable.