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1.
Background: Young children from disadvantaged settings often present delays in fundamental motor skills (FMS). Young children can improve their FMS delays through developmentally appropriate motor skill intervention programming. However, it is unclear which pedagogical strategy is most effective for novice and expert instructors.

Purpose: The purpose of this study was to examine the effects of a motor skill intervention delivered by expert and novice teachers via direct or indirect pedagogical strategy on the object control and locomotor skills of young children.

Participants and setting: Participants included children (N?=?109) aged 40–67 months (Mage?=?54 months, SD?=?7 months) enrolled in an early years center for children who are socioeconomically disadvantaged in the United States.

Data collection: Children participated in one of five instructional conditions (expert-led direct, expert-led indirect, novice-led direct, novice-led indirect, and control). Expert and preservice physical education teachers implemented the Successful Kinesthetic Instruction for Preschoolers (SKIP) motor skill program twice weekly for 6 weeks (360?min of instruction). Children in all experimental conditions (n?=?69) received ‘business as usual’ free play on nonintervention days. Children in the control condition (n?=?40) received the ‘business as usual’ free play 5 days weekly throughout the entirety of the intervention. Children completed the Test of Gross Motor Development-2 during the pretest and the posttest.

Data analysis: For object control and locomotor skills, we conducted two, separate, one-way ANOVAs at the pretest to determine condition differences. We then calculated two separate, five conditions × two times repeated-measures ANOVAs to determine the effects of SKIP on both object control and locomotor skills. Tukey post hoc analyses confirmed posttest differences among the conditions.

Findings: There were no significant differences among conditions at the pretest (locomotor, p?=?.347–.969; object control, p?=?.143–.918). For object control skills, there were significant main effects for time (F[1, 104]?=?83.92, p?.001, η2?=?.45) and condition (F[4, 104]?=?6.39, p?<?.001, η2?=?.20) as well as a significant time by condition interaction (F[4, 104]?=?22.36, p?<?.001, η2?=?.45). For locomotor skills, there was a significant main effect for time (F[1, 104]?=?41.25, p?<?.001, η2?=?.28) but not for condition (F[4, 104]?=?2.20 p?<?.074, η2?=?.08). There was a significant time by condition interaction (F[1, 104]?=?18.68, p?<?.001, η2?=?.42). Experts, regardless of strategy, showed significantly greater improvements (p?<?.001) than novice and control conditions for locomotor skills. For object control skills, experts (all conditions) and novice-direct demonstrated significantly (p?<?.001) greater gains than the control and novice-indirect conditions.

Conclusion: Young children from disadvantaged settings demonstrated developmental delays with FMS. Motor skill intervention was effective with remediating their delays. Novice teachers with limited physical education experience should begin teaching object control skills via direct instruction. Experts can choose either direct or indirect instructional strategies. Future research should investigate the implications of scaffolding locomotor skills and indirect pedagogical strategies for novice teachers.  相似文献   

2.
Abstract

No published research has assessed sleep patterns of elite rugby union players following match-play. The present study examined sleep patterns of professional rugby union players, prior and post-match-play, to assess the influence of competition. Twenty-eight male rugby union players (24.4?±?2.9 years, 103.9?±?12.2?kg) competed in one of four competitive home matches. Player's sleep behaviours were monitored continuously using an Actiwatch® from two days before the match, until three days post-match. Repeated measures of analysis of variance (ANOVA) showed significant differences across the time points measured for time to bed (F?=?26.425, η2 ?=?0.495, p < .001), get up time (F?=?21.175, η2?=?0.440, p?<?.001), time spent in bed (F?=?10.669, η2?=?0.283, p?<?.001), time asleep (F?=?8.752, η2?=?0.245, p?<?.001) and percentage of time moving (F?=?4.602, η2?=?0.146 p?<?.05). Most notable, post hocs revealed a significant increase for time in bed the night before the match (p?<?.01; 95% CI?=?0?:?10–1?:?28?h; 9.7?±?13.5%) compared with the reference night sleep. Furthermore, time asleep significantly decreased post-match (p?<?.05; 95% CI?=??0:03 to ?1:59?h; ?19.5?±?19.8%) compared to two nights pre-match. Across all time points, sleep latency and efficiency for most players were considered abnormal compared to that expected in normal populations. The results demonstrate that sleep that is deprived post-match may have detrimental effects on the recovery process.  相似文献   

3.
The goal of this randomized, double-blind, cross-over study was to assess the acute effects of caffeine ingestion on muscular strength and power, muscular endurance, rate of perceived exertion (RPE), and pain perception (PP) in resistance-trained men. Seventeen volunteers (mean?±?SD: age?=?26?±?6 years, stature?=?182?±?9?cm, body mass?=?84?±?9?kg, resistance training experience?=?7?±?3 years) consumed placebo or 6?mg?kg?1 of anhydrous caffeine 1?h before testing. Muscular power was assessed with seated medicine ball throw and vertical jump exercises, muscular strength with one-repetition maximum (1RM) barbell back squat and bench press exercises, and muscular endurance with repetitions of back squat and bench press exercises (load corresponding to 60% of 1RM) to momentary muscular failure. RPE and PP were assessed immediately after the completion of the back squat and bench press exercises. Compared to placebo, caffeine intake enhanced 1RM back squat performance (+2.8%; effect size [ES]?=?0.19; p?=?.016), which was accompanied by a reduced RPE (+7%; ES?=?0.53; p?=?.037), and seated medicine ball throw performance (+4.3%, ES?=?0.32; p?=?.009). Improvements in 1RM bench press were not noted although there were significant (p?=?.029) decreases in PP related to this exercise when participants ingested caffeine. The results point to an acute benefit of caffeine intake in enhancing lower-body strength, likely due to a decrease in RPE; upper-, but not lower-body power; and no effects on muscular endurance, in resistance-trained men. Individuals competing in events in which strength and power are important performance-related factors may consider taking 6?mg?kg?1 of caffeine pre-training/competition for performance enhancement.  相似文献   

4.
This investigation examined the oxidative stress (F2-Isoprostane; F2-IsoP) and inflammatory (interleukin-6; IL-6) responses to repeat-sprint training in hypoxia (RSH). Ten trained male team sport athletes performed 3(sets)*9(repetitions)*5?s cycling sprints in simulated altitude (3000?m) and sea-level conditions. Mean and peak sprint power output (MPO and PPO) were recorded, and blood samples were collected pre-exercise, and again at 8 and 60?min post-exercise. Both MPO and PPO were significantly reduced in hypoxia (compared to sea-level) in the second (MPO: 855?±?89 vs. 739?±?95?W, p?=?.006; PPO: 1024?±?114 vs. 895?±?112?W, p?=?.010) and third (MPO: 819?±?105 vs. 686?±?83?W, p?=?.008; PPO: 985?±?125 vs. 834?±?99?W, p?=?.008) sets, respectively. IL-6 was significantly increased from pre- to 1?h post-exercise in both hypoxia (0.7?±?0.2 vs. 2.4?±?1.4?pg/mL, p?=?.004) and sea-level conditions (0.7?±?0.2 vs. 1.6?±?0.3?pg/mL, p?d?=?0.80) suggesting higher IL-6 levels of post-hypoxia. F2-IsoP was significantly lower 1?h post-exercise in both the hypoxic (p?=?.005) and sea-level (p?=?.002) conditions, with no differences between trials. While hypoxia can impact on exercise intensity and may result in greater post-exercise inflammation, it appears to have little effect on oxidative stress. These results indicate that team sport organisations with ready access to hypoxic training facilities could confidently administer RSH without significantly increasing the post-exercise inflammatory or oxidative stress response.  相似文献   

5.
Abstract

We sought to examine whether the relationship between recovery–stress factors and performance would differ at the beginning (Stage 1) and the end (Final Stage) of a multi-stage cycling competition. Sixty-seven cyclists with a mean age of 21.90 years (SD?=?1.60) and extensive international experience participated in the study. The cyclists responded to the Recovery–Stress Questionnaire for Athletes (RESTQ-Sport) and rated their performance (1?=?extremely poor to 10?=?excellent) in respect to the first and last stage. Two step-down multiple regression models were used to estimate the relationship among recovery (nine factors; e.g. Physical Recovery, Sleep Quality) and stress factors (10 factors; e.g. Lack of Energy, Physical Complaints), as assessed by the RESTQ-Sport and in relation to performance. Model 1 pertained to Stage 1, whereas Model 2 used data from the Final Stage. The final Model 1 revealed that Physical Recovery (β?=?.46, p?=?.01), Injury (β?=??.31, p?=?.01) and General Well-being (β?=??.26, p?=?.04) predicted performance in Stage 1 (R2?=?.21). The final Model 2 revealed a different relationship between recovery–stress factors and performance. Specifically, being a climber (β?=?.28, p?=?.01), Conflicts/Pressure (β?=?.33, p?=?.01), and Lack of Energy (β?=??.37, p?=?.01) were associated with performance at the Final Stage (R2?=?.19). Collectively, these results suggest that the relationship among recovery and stress factors changes greatly over a relatively short period of time, and dynamically influences performance in multi-stage competitions.  相似文献   

6.
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7.
ABSTRACT

Background: Physical education (PE) can be considered the centrepiece of school physical literacy (PL) programs, but ineffective lessons or an absence of PE across the public primary school system has raised concern. This study aimed to evaluate the implementation, acceptability and impact of teacher delivery of PE as part of a multicomponent Physical Education Physical Literacy (PEPL) approach, designed to improve classroom teachers’ provision of PE and PL opportunities within a cluster of suburban primary schools.

Method: Within a pragmatic randomised cluster-based trial with mixed methods, a PEPL coach was appointed to seven schools for one school year, with another seven schools continuing their usual practice as the control group. The coach’s role was to support and professionally develop classroom teachers to teach PE and to create opportunities that develop PL inside and outside the school environment. Focusing on Grade 5 teachers, the implementation, acceptability and teacher impact were assessed using direct observations of PE teaching style, a daily log kept by the coach and interviews with principals and teachers.

Results: The PEPL coach visited each school on average once a week for the 33 available weeks of the school year. There were several positive effects for teachers and schools. With no classroom teacher initially taking PE or classroom physical activity breaks, all seven teachers regularly introduced a PE lesson and activity breaks into their weekly schedule. PE class instructional time increased (intervention; +4.8 vs. control; ?3.5 min/lesson; β?=?1.69; SE?=?0.76; p?=?.05), with lessons of greater duration (intervention; +8.6 vs. control +1.9 min/lesson; β?=?1.14, SE?=?0.58, p?=?.05) and moderate and vigorous physical activity increased 5.7 min in intervention classes (p?<?.05). The PEPL coach introduced regular physical activities before and after school and linked the schools with a national sports coaching scheme. Interviews indicated that the PEPL approach was both valued and well-accepted by staff, that classroom teacher confidence to teach PE increased and that principals perceived a shift toward a school ‘culture’ of physical activity.

Conclusions: Well-received by classroom teachers and principals, the PEPL approach resulted in classroom teachers introducing both PE and activity breaks into their weekly teaching program and schools were linked to external sport coaching programs. These effects suggest that the PEPL approach enhanced opportunities for the development of physical literacy in this suburban primary school setting.

Trial registration: Australian New Zealand Clinical Trials Registry identifier: ACTRN12615000066583.  相似文献   

8.
ABSTRACT

Background: Health organisations such as the United Nations continue to place an expectation on school physical education (PE) programmes and wider school strategies to ensure students develop physical literacy and receive the well-established benefits of meeting physical activity guidelines. Barriers to meet this expectation such as lack of trained PE teachers, lack of time and greater emphasis on academic achievement are ongoing challenges to schools. The purpose of this study was to evaluate the impact of the multi-component Physical Education Physical Literacy (PEPL) intervention, designed to improve students’ fundamental movement skill, perceived physical abilities and level of physical activity.

Method: A qualified PE teacher implemented the PEPL intervention across seven schools, and another seven schools formed a control group as part of a randomised cluster-based trial. Grade 5 students (N?=?318, age 10.4 years?±?SD 0.4) completed assessments of physical activity, fundamental movement skill, attitudes towards PE, and self-perceptions of physical abilities before and after a 33-week intervention. Intervention effects were examined using general linear mixed models. Post-intervention focus groups with students were used to develop insights into experiences and outcomes.

Results: With no significant gender interactions, the PEPL approach led to enhanced object control skills (β?=?1.62; SE?=?0.61; p?=?0.008), with little evidence of any other fundamental movement skill improvements in excess of those in the control group. There was also modest evidence for an effect on accelerometer measured moderate-to-vigorous physical activity (MVPA) during school time (β?=?4.50; SE?=?2.39; p?=?0.058), but this was not accompanied by any significant intervention effect over the entire week. Questionnaires indicated students in the PEPL programme became less satisfied with their own sporting ability (β?=??0.20; SE?=?0.08; p?=?0.013) but qualitative data analyses suggested that they enjoyed the PEPL approach experience, becoming more motivated and confident in their physical abilities.

Conclusions: Evidence of enhanced object control skill, increased confidence and motivation to be physically active, and moderate evidence of more MVPA during school time, indicate that the introduction of the PEPL approach contributed to the development of student physical literacy. A decrease in perceived sporting competence warrants greater attention on student’s self-perceptions in future iterations of the intervention.

Trial registration: Australian New Zealand Clinical Trials Registry identifier: ACTRN12615000066583.  相似文献   

9.
Purpose: The goal of this study was to determine the effects of repeated-sprint training in hypoxia induced by voluntary hypoventilation at low lung volume (VHL) on running repeated-sprint ability (RSA) in team-sport players.

Methods: Twenty-one highly trained rugby players performed, over a 4-week period, seven sessions of repeated 40-m sprints either with VHL (RSH-VHL, n?=?11) or with normal breathing (RSN, n?=?10). Before (Pre-) and after training (Post-), performance was assessed with an RSA test (40-m all-out sprints with a departure every 30?s) until task failure (85% of the reference velocity assessed in an isolated sprint).

Results: The number of sprints completed during the RSA test was significantly increased after the training period in RSH-VHL (9.1?±?2.8 vs. 14.9?±?5.3; +64%; p?p?=?.74). Maximal velocity was not different between Pre- and Post- in both groups whereas the mean velocity decreased in RSN and remained unchanged in RSH-VHL. The mean SpO2 recorded over an entire training session was lower in RSH-VHL than in RSN (90.1?±?1.4 vs. 95.5?±?0.5%, p?Conclusion: RSH-VHL appears to be an effective strategy to produce a hypoxic stress and to improve running RSA in team-sport players.  相似文献   

10.
The purpose of the study was to examine the perspectives of both academics and practitioners in relation to forming applied collaborative sport science research within team sports. Ninety-three participants who had previously engaged in collaborative research partnerships within team sports completed an online survey which focused on motivations and barriers for forming collaborations using blinded sliding scale (0–100) and rank order list. Research collaborations were mainly formed to improve the team performance (Academic: 73.6?±?23.3; Practitioner: 84.3?±?16.0; effect size (ES?=?0.54), small). Academics ranked journal articles’ importance significantly higher than practitioners did (Academic: Mrank?=?53.9; Practitioner: 36.0; z?=??3.18, p?=?.001, p?q). However, practitioners rated one-to-one communication as more preferential (Academic: Mrank?=?41.3; Practitioner 56.1; z?=??2.62, p?=?.009, p?q). Some potential barriers were found in terms of staff buy in (Academic: 70.0?±?25.5; Practitioner: 56.8?±?27.3; ES?=?0.50, small) and funding (Academic: 68.0?±?24.9; Practitioner: 67.5?±?28.0; ES?=?0.02, trivial). Both groups revealed low motivation for invasive mechanistic research (Academic: 36.3?±?24.2; Practitioner: 36.4?±?27.5; ES?=?0.01, trivial), with practitioners have a preference towards ‘fast’ type research. There was a general agreement between academics and practitioners for forming research collaborations. Some potential barriers still exist (e.g. staff buy in and funding), with practitioners preferring ‘fast’ informal research dissemination compared to the ‘slow’ quality control approach of academics.  相似文献   

11.
The aim of this study was to compare the effects of two different intensity distribution training programmes (polarized (POL) and threshold (THR)) on aerobic performance, strength and body composition variables in ultra-endurance runners. Twenty recreationally trained athletes were allocated to POL (n?=?11; age: 40.6?±?9.7 years; height: 175.4?±?7?cm; weight: 73.5?±?10.8?kg; fat mass 18.4?±?6.0%; VO2max: 55.8?±?4.9?ml/kg/min) or THR group (n?=?9; age: 36.8?±?9.2 years; height: 178.5?±?4.2?cm; weight: 75.5?±?10.4?kg; fat mass 14.9?±?5.3%; VO2max: 57.1?±?5.2?ml/kg/min) and performed the 12 weeks training programme. Both programmes had similar total time and load but a different intensity distribution (POL?=?79.8?±?2.1% in Zone 1; 3.9?±?1.9% in Zone 2; 16.4?±?1.5% in Zone 3; THR?=?67.2?±?4.6% in Zone 1; 33.8?±?4.6% in Zone 2; 0% in Zone 3). Body composition, isokinetic strength and aerobic running performance were measured before and after each programme. Both groups decreased fat mass after training (POL= Δ–11.2%; p?=?.017; ES?=?0.32; THR= Δ–18.8%; p?p?=?0.003; ES?=?0.71) and 12?km/h (Δ–4.5%; p?=?.026; ES?=?0.73) and running time to exhaustion (Δ2.4%; p?=?.011; ES?=?0.33). No changes were observed in strength and no significant differences were observed between the group in any variable. Compared with THR distribution, 12 weeks of POL training efficiently improves aerobic performance in recreational ultra-endurance runners.  相似文献   

12.
Background: Motor skill (MS) competence is an important contributing factor for healthy development.

Purpose: The goal was to test the effectiveness of primary school physical education (PE) on MS and physical fitness (PF) development.

Methods: Three classes (n?=?60, aged 9.0?±?0.9) were randomly assigned to three diverse conditions during a school year: two PE lessons/week (PE-2), three PE lessons/week (PE-3), and no PE lessons control group (CG). BMI, skinfolds, PF (9-min run/walk, sit-up, modified pull-ups), gymnastics, soccer, handball, basketball and track-and-field skills were evaluated. Effect sizes (d) were reported as magnitude of change.

Results: Skinfolds significantly increased only in CG (d?=?1.21). PF composite z-scores improved in PE-3 (d?=?0.61), but decreased in PE-2 (d?=?0.57), and had no changes in CG. Statistically significant improvement was verified in gymnastics and handball skills in both experimental groups (gymnastic: d?=?2.95 and d?=?2.61 for PE-3 and PE-2, respectively; handball: d?=?1.87 and d?=?0.57 for PE-3 and PE-2, respectively), and no changes were seen in CG. In soccer, there were improvements only in the PE-3 (d?=?0.55), and in basketball only in PE-2 (d?=?0.46). There were no changes in any group for track-and-field skills.

Conclusions: PE programs can effectively promote PF and MS development.  相似文献   

13.
The purpose of this study is to analyse the effect of 12 weeks of non-linear resistance training (NLRT) on anthropometry, muscle strength and inflammatory biomarkers in persons infected with human immunodeficiency virus (PIHIV). Thirty previously sedentary PIHIVs were randomized into the NLRT (n?=?15) and control (CON, n?=?15) groups. NLRT group were submitted to 12 weeks of training, whereas the CON group maintained their daily habits. At baseline and after 12 weeks, both groups underwent anthropometric evaluations and blood sampling for the analysis of inflammatory biomarkers. Analysis of covariance using preintervention values as covariate was performed to determine the effects of exercise on anthropometry, muscle strength, cytokines levels and T cells. Significance was set at p?p?p p?=?.009), blood levels of interleukin (IL)-1β (p?=?.029), IL-6 (p?=?.005), IL-8 (p?=?.010), and tumour necrosis factor (TNF)-α (p?=?.001) and an increase in muscle strength (p?p?=?.030) and CD4+ (p?=?.004) and CD8+ (p?相似文献   

14.
ABSTRACT

AIM: To investigate the association of electrocardiographic (ECG) left and/or right ventricular hypertrophy (LVH and RVH) with physical fitness of military males.

METHODS: We used a military cohort of 2587 males, who were on average 29.1 years of age, from the cardiorespiratory fitness and hospitalization events in armed forces (CHIEF) study in Taiwan for the analysis. Isolated ECG-LVH (n?=?779) was diagnosed by either the Sokolow-Lyon or Cornell voltage criteria. Isolated ECG-RVH (n?=?234) was defined by either the Sokolow-Lyon or Myers et al. voltage criteria. Combined ECG-LVH/RVH (n?=?140) was defined as those who met the voltage criteria for both LVH and RVH. The other ECGs were defined as unaffected (n?=?1434). Physical fitness was evaluated by the upper and lower 16% exercise performance (beyond 1-standard deviation) in 3000-meter run, 2-minute sit-ups, and 2-minute push-ups. All procedures were standardized and monitored by unified computerized scoring systems. A multiple logistic regression was used to determine the relationship.

RESULTS: Compared with unaffected participants, those with an isolated ECG-LVH were tended to have a better 3000-meter run performance (odds ratio (OR) and 95% confidence intervals: 1.22 [0.99–1.50], p-value?=?0.064) after adjusting for age, service specialty, body mass index, mean blood pressure, smoking status, alcohol intake, hemoglobin level, and exercise frequency. By contrast, those with an isolated ECG-RVH were tended to have a worse 2-minute sit-up performance (OR: 1.46 [0.99–2.16], p-value?=?0.054).

CONCLUSION: Military males with ECG-LVH and/or ECG-RVH compared to unaffected participants may have diverse exercise performances. However, these observations narrowly failed to reach statistical significance.  相似文献   

15.
β-hydroxy-β-methylbutyrate (calcium: HMB-Ca and free acid: HMB-FA) and α-hydroxyisocaproic acid (α-HICA) are leucine metabolites that have been proposed to improve body composition and strength when combined with resistance exercise training (RET). In this double-blind randomized controlled pragmatic trial, we evaluated the effects of off-the-shelf supplements: α-HICA, HMB-FA and HMB-Ca, on RET-induced changes in body composition and performance. Forty men were blocked randomized to receive α-HICA (n?=?10, fat-free mass [FFM]?=?62.0?±?7.1?kg), HMB-FA (n?=?11, FFM?=?62.7?±?10.5?kg), HMB-Ca (n?=?9, FFM?=?65.6?±?10.1?kg) or placebo (PLA; n?=?10, FFM?=?64.2?±?5.7?kg). The training protocol consisted of a whole-body resistance training routine, thrice weekly for 8 weeks. Body composition was assessed by dual-energy x-ray absorptiometry (DXA) and total body water (TBW) by whole-body bioimpedance spectroscopy (BIS), both at baseline and at the end of weeks 4 and 8. Time-dependent changes were observed for increase in trunk FFM (p?相似文献   

16.
Abstract

Hypoxic training methods are increasingly being used by researchers in an attempt to improve performance in normoxic ambients. Moreover, previous research suggests that resistance training in hypoxia can cause physiological and muscle adaptations. The primary aim of this study was to compare the effects of 8 weeks of high-intensity resistance circuit-based (HRC) training in hypoxia on body composition and strength performance. The secondary aim was to examine the effects of HRC on metabolic parameters. Twenty-eight male participants were randomly assigned to either hypoxia (Fraction of inspired oxygen [FIO2]?=?15%; HRChyp: n?=?15; age: 24.6?±?6.8 years; height: 177.4?±?5.9?cm; weight: 74.9?±?11.5?kg) or normoxia [FIO2]?=?20.9%; HRCnorm: n?=?13; age: 23.2?±?5.2 years; height: 173.4?±?6.2?cm; weight: 69.4?±?7.4?kg) groups. Training sessions consisted of two blocks of three exercises (Block 1: bench press, leg extension and front pull down; Block 2: deadlift, elbow flexion and ankle extension). Each exercise was performed at six repetition maximum. Rest periods lasted for 35-s between exercises, 3-min between sets and 5-min between blocks. Participants exercised twice weekly for 8 weeks, and body composition, strength and blood tests were performed before and after the training program. Lean body mass and bone mineral density significantly increased over time in the HRChyp (p?<?.005; ES?=?0.14 and p?<?.014; ES?=?0.19, respectively) but not in the HRCnorm after training. Both groups improved their strength performance over time (p?<?.001), but without group effect differences. These results indicate that simulated hypoxia during HRC exercise produced trivial effects on lean body mass and bone mineral density compared to normoxia.  相似文献   

17.
Objective: The acute responses to resistance training (RT) between males and females are poorly understood, especially from a neural perspective. Therefore, we aimed to compare the corticospinal and intracortical responses during fatigue and recovery following RT.

Methods: Twenty-two participants (12M, 10F) completed one-session of RT (3?×?12 repetition maximum) unilateral leg extensions with 60?s recovery. Single- and paired-pulse transcranial magnetic stimulation measured changes in the motor-evoked potential (MEP), corticospinal silent period (CSP), CSP/MEP ratio, and intracortical facilitation/inhibition (ICF, SICI). The maximal compound wave (MMAX) measured peripheral excitability of the rectus femoris (RF) and maximal voluntary isometric contraction (MVIC) neuromuscular function of the leg extensors. Measures were taken immediately post, 30?min, 1 and 6?h post-training.

Results: A significantly greater increase in MEP/MMAX ratio (p?=?.005) was observed for females immediately post-training compared to males. While no sex differences in MEP/MMAX ratio was observed at 30?min and 1?h post-training, a greater MEP/MMAX ratio for males was observed at 30?min (p?p?=?.003). CSP trended to decrease for males compared to females immediately post-training (d?=?1.93). MVIC was decreased post-training for males; 14.22% and females; 14.16% (P?MAX reduced at 30?min for both groups (P?P?>?.05).

Conclusion: The net output of corticospinal excitability is similar between males and females during fatigue. However, the mechanism in which this is modulated (increased MEP, decreased CSP) appears to be sex-specific.  相似文献   

18.
Abstract

This study aimed to understand the kinematic and kinetic differences between two sprint starts: block and split-stance standing. Fourteen sub-elite male sprinters (100 m time: 11.40?±?0.39?s) performed block and split-stance standing starts sprints over 30 m of in-ground force platforms in a randomised order. Independent t-tests and repeated measures mixed model analysis of variance were used to analyse the between-condition variables across conditions, and over four step phases. Block start sprints resulted in significantly (p?<?.05) faster 5 m (5.0%, effect size [ES]?=?0.89) and 10?m (3.5%, ES?=?0.82) times, but no significant differences were found at 20 and 30?m. No significant differences were found in any kinematic measure between starting positions. However, block starts resulted in significantly (p?<?.001) greater propulsive impulses (6.8%, ES?=?1.35) and net anterior-posterior impulses (6.5%, ES?=?1.12) during steps 1–4, compared to the standing start. Block starts enable athletes to produce a greater amount of net anterior-posterior impulse during early accelerated sprinting, resulting in faster times up to 10 m. When seeking to improve initial acceleration performance, practitioners may wish to train athletes from a block start to improve horizontal force production.  相似文献   

19.
Abstract

The aim of this study was to analyse the pacing strategies adopted by elite male and female marathon runners when setting every world record since 1998. For data analysis, the total distance of the marathon was divided into eight sections of 5?km and a final section of 2.195?km, and the relative average speed of each section was calculated individually. Female athletes maintained similar speeds in the first and second half of the marathon (ES?=?0.22, small effect, p?=?0.705), whereas male athletes increased their speed as the marathon progressed (ES?=?1.18, moderate effect, p?=?0.011). However, no differences were observed between men and women in either the first (ES?=?0.56, small effect, p?=?0.290), or in the second half of the marathon (ES?=?0.60, moderate effect, p?=?0.266). When comparing the women’s world records (1998–2003) vs. men’s records (1998–2018) by sections, we observed differences at the beginning of the race (second section, ES?=?0.89, moderate effect) and at the end (last section, ES?=?0.87, moderate effect). The pace variations during the race were similar between male athletes and that of women with male pacemakers (1.53%?±?0.60 vs. 1.68%?±?0.84, respectively). However, a trend towards higher pace variations during the race in the female records with female pacemakers was observed (2.28%?±?0.95). This study shows how male and female marathon records in the last 20 years have been set using different pacing strategies. While men used a negative strategy (faster finishing), women used a less uniform pacing strategy.  相似文献   

20.
Background: School physical education (PE) programs provide a prime environment for interventions that attempt to develop school-aged children’s motor competence and overall physical fitness, while also stimulating competence motivation to engage in physical activity during childhood. It is generally recognized that a pedometer-based intervention strategy combined with a goal-setting strategy may be effective in increasing physical activity participation among school-aged children. The purpose of this study was to evaluate the impact of an 8-week pedometer-based goal-setting intervention on children’s motivation in PE, motor competence, and physical activity.

Methods: A pretest–posttest comparison group design was used with the 8-week intervention (3 days/week for 24 sessions). Participants were 273 (boys?=?136, girls?=?137) students recruited from 3 elementary schools in the US. Classes in each school were randomly allocated to three experimental conditions: (1) an intervention group with a personalized pedometer weekly target to reach in their PE class (N?=?110), (2) an intervention group with the fixed pedometer target range to reach in each PE class based on the recommended criteria (N?=?90), or (3) a control group without intervention (N?=?73).

Analysis/results: The factorial repeated measures MANOVA indicated significant multivariate effects for the group [F(6, 528)?=?12.954, p?Post hoc analyzes showed that both experimental groups had significantly higher expectancy-value beliefs, motor competence, and physical activity compared to the control group (p?Conclusions: Health practitioners should be aware that goal-directed action can contribute to school students’ PE-related achievement motivation, motor competence, and achieving the recommended 60?min of moderate-to-vigorous physical activity.  相似文献   

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