Leg Muscle Metabolism in Trained and Untrained Men

The purpose of this study was to describe substrate changes in blood and muscles during submaximal exercise and to look at the relationship of these changes to some enzyme activities important in lipid and carbohydrate metabolism. A group of six trained and six untrained men were exercised for 1 hour at 50% [Vdot]O₂ max; three from each group cycled and the rest ran on a treadmill. During the exercise, blood-free fatty acid (FFA) levels increased twofold, glycerol by 3.6 times, triglyceride (TG) by 11/100 ml, and glucose by a mean 11 mg/100 ml in the trained men. In the untrained subjects, however, FFA increased 1.8 fold, glycerols 1.6 fold, and TG by a mean 24/100 ml. Glucose fell in every subject by an average 5 mg%. Muscle glycogen depletion averaged 34 mmoles/kg in the untrained and 23 mmoles/kg in the trained group. The activities of succinic acid dehydrogenase (SDH), malic acid dehydrogenase (MDH), and carnitine palmityl transferase (CPT) were greater by 177%, 93%, and 64%, respectively, in the trained group than in the untrained subjects. The results indicated that at the same percent [Vdot]O₂ max, the trained men seemed to “preferentially” use FFA as an energy source, possibly due to a well developed Krebs cycle and increased CPT activities. This preference would tend to inhibit the major rate-limiting enzymes of glycolysis, thus slowing even further the use of carbohydrates as an energy source. The differences in response to exercise were independent of fiber type and indicate that these catabolic responses were primarily due to aerobic training.     

运动传感器在肥胖运动干预管理中的研究 与应用前景

现代生活方式的改变是肥胖发生率不断攀高的重要推手.一方面,体力活动不足和营养过剩是肥胖发生的重要原因;另一方面,这些环境因素的改变或调整也是治疗肥胖的重要手段.本文从体力活动与健康关系引入肥胖者能量收支平衡的重要性及运动干预过程中能量消耗监测与反馈的方法,系统回顾体力活动的监控方法,介绍运动传感器尤其是加速度计在肥胖人群体力活动监控中的发展与应用,分析加速度计在全民健身监测中的优势与劣势,面临的发展瓶颈,探索加速度计在运动能量消耗监测与管理中的应用前景.     

Physical activity in the lifestyle of Czech university students: Meeting health recommendations

Abstract

The decline of physical activity (PA) in adults as well as children and youth is a worldwide phenomenon. The aim of this study is to analyse the amount of PA in Czech university students' daily lives. The research on university students was conducted as part of nationwide research on PA in the adult population of the Czech Republic. A total of 906 students at eight selected universities were asked to participate in this study. The response rate was 79.5%. We analysed data from 641 university students: 318 male [mean age 21.63±1.73; mean Body Mass Index (BMI) 23.50±1.91] and 323 female (mean age 21.08±1.53; mean BMI 21.23±2.20). The students wore Yamax SW-701 pedometers continuously for seven days. With respect to BMI, the recommendation of 10,000 steps per day on an average day was met by 76% of men and 68% of women of normal weight, 67% of male students who were overweight or obese and 85% of female students who were overweight or obese. Of all monitored days, in both females and males, the number of steps taken on Sunday was significantly lower (p<0.0001) in comparison to other days of a week. No significant differences were found in the number of steps taken among students of normal weight, students who were overweight and students who were obese on any of the monitored days. The majority of Czech male university students are of normal weight. Only 9% of students meet the criterion of 10,000 steps every day. Approximately two-thirds of students meet the 10,000 steps daily criterion on four or more days per week. The lowest number of steps is taken on Sundays; this finding supports the need for intervention programmes to enhance PA on weekends.     

体育生活方式与健康

健康是人类生存发展的基本要素，随着科学技术的发展和人民生活水平的提高．生活方式的变化，出现许多现代文明病。本文主要探计生活方式、体育生活方式与健康之间的关系，以此促进人们提高生活质量，建立健康、文明和科学的体育生活方式。     

The translation of preschoolers’ physical activity guidelines into a daily step count target

This study aimed at translating the physical activity (PA) guideline (180 min of total PA per day) into a step count target in preschoolers. 535 Flemish preschoolers (mean age: 4.41 ± 0.58) wore an ActiGraph accelerometer (GT1M, GT3X and GT3X+) – with activated step count function – for four consecutive days. The step count target was calculated from the accelerometer output using a regression equation, applying four different cut-points for light-to-vigorous PA: Pate, Evenson, Reilly, and Van Cauwenberghe. The present analysis showed that 180 min of total PA per day is equivalent to the following step count targets: 5,274 steps/day using the Pate cut-point, 4,653 steps/day using the Evenson cut-point, 11,379 steps/day using the Reilly cut-point and 13,326 steps/day using the Van Cauwenberghe cut-point. Future studies should focus on achieving consensus on which cut-points to use in preschoolers before a definite step count target in preschoolers can be proposed. Until then, we propose to use a provisional step count target of 11,500 steps/day as this step count target is attainable, realistic and helpful in promoting preschoolers’ PA.     

Accelerometry-Based Characteristics of Overall Sedentary Behavior and Sitting in Middle-Aged Adults

ABSTRACT

The purpose of this study was to describe the accelerometry-based characteristics of overall sedentary behavior (SB) and sitting among adults under free-living conditions. Thirty-six (mean age 47.6 years) volunteers carried a waist-worn accelerometer for ≥4 days with data ≥600 min/d during 14 consecutive days. A machine learning (ML) based method was used to classify the patterns of SB and sitting from raw 3D acceleration. The participants spent most (69.3%) of their waking time in SB, and a half (52.2%) of the SB was performed in a sitting posture. Men broke their overall sedentary time less often (4.1 vs. 6.1 bouts/h), but women sat more; however, women broke their sitting time as often as men (7.6 bouts/h). This study confirms that SB and sitting can be distinguished using ML methods, and more information about SB can be achieved when overall SB and sitting are analyzed separately in free-living conditions.     

Effects of Proximity on the Choice to Be Physically Active or Sedentary

The link between physical activity and weight loss has precipitated interest in interventions to foster adherence to exercise. It has been suggested that treatment effects, when significant, should be analyzed to determine theory-based mediators. This research assessed possible mediation of changes in Physical Self-Concept, Exercise Self-Efficacy, Total Mood Disturbance, and Body Areas Satisfaction scores on the relationship between exercise session attendance and participation by obese women in a 6-month treatment based on tenets of social cognitive theory (n = 73) or a control condition (n = 64). Participation in the treatment was associated with significantly greater exercise session attendance and significantly greater improvements in Physical Self-Concept, Exercise Barriers Self-Efficacy, and Body Areas Satisfaction. Overall, changes in the assessed psychological factors demonstrated significant mediation of the association between group membership and exercise session attendance, R² = .23, with only change in Physical Self-Concept scores providing a significant unique contribution. Extensions of this research across different sample types, and with longer durations, were suggested to refine theory and, ultimately, improve exercise adherence treatments.     

北京市成年人身体机能状况的调查研究

本文通过对北京市成年人体质测试,进行人体机能分析研究。测试对象为北京市市民,男子18至59岁,女子18至54岁,男子共3806人,女子共3568人。对测试中的机能指标——脉搏、血压、肺活量、台阶指数进行了分析,脉搏、肺活量和肺活量/体重的变化是随年龄的增长而下降,下降过程有起伏;收缩压、舒张压和台阶指数的变化是随年龄的增长而上升,上升过程中有起伏。这些指标的变化规律有阶段性,以下降的幅度、速度和T检验的结果划分为31～35岁,41～45岁,51～55岁3个阶段,不同指标各阶段下降情况与锻炼身体有很大关系。成年人18～20岁组与1985年中学生(18岁组)进行比较,发现成年人18～20岁的指标结果与中学生差异很大,成年人18～20岁组的机能状况不如18岁组的中学生。     

Social Physique Anxiety and Intention to Be Physically Active: A Self-Determination Theory Approach

Purpose: Based on self-determination theory, the purpose of this study was to analyze the relationship between social physique anxiety and intention to be physically active, while taking into account the mediating effects of the basic psychological needs and behavioral regulations in exercise. Method: Having obtained parents' prior consent, 390 students in secondary school (218 boys, 172 girls; M_age = 15.10 years, SD = 1.94 years) completed a self-administered questionnaire during physical education class that assessed the target variables. Preliminary analyses included means, standard deviations, and bivariate correlations among the target variables. Next, a path analysis was performed using the maximum likelihood estimation method with the bootstrapping procedure in the statistical package AMOS 19. Results: Analysis revealed that social physique anxiety negatively predicted intention to be physically active through mediation of the basic psychological needs and the 3 autonomous forms of motivation (i.e., intrinsic motivation, integrated regulation, and identified regulation). Conclusion: The results suggest that social physique anxiety is an internal source of controlling influence that hinders basic psychological need satisfaction and autonomous motivation in exercise, and interventions aimed at reducing social physique anxiety could promote future exercise.     

The Heart Rate Response to Nintendo Wii Boxing in Young Adults

Purpose

To determine if 30 minutes of Nintendo Wii Sports boxing provides cardiorespiratory benefits and contributes to the daily exercise recommendations for healthy young adults.

Methods

Twenty healthy 23- to 27-year-olds participated in two sessions to measure maximum heart rate (HR_max) via a treadmill test and heart rate (HR) response to 30 minutes of Wii Sports boxing. Heart rate in beats per minute (bpm) was measured continuously, and exercise intensity during each minute of play was stratified as a percentage of HR_max. Mixed designs analysis of variance (ANOVA) and Pearson product moment correlations were used to analyze the data.

Results

Mean (SD) HR response to boxing was 143 (15) bpm or 77.5% (10.0%) of HR_max. The mean HR response for experienced participants was significantly lower than inexperienced participants, P = .007. The ANOVA revealed a significant interaction between experience and time spent at various intensities, P = .009. Experienced participants spent more time in light to vigorous intensities, inexperienced participants in moderate to very hard intensities. Fitness was not correlated with mean HR response to boxing, P = .49.

Conclusion

Thirty minutes of Nintendo Wii Sports boxing provides a moderate to vigorous aerobic response in healthy young adults and can contribute to daily recommendations for physical activity.Key Words: exergaming, cardiorespiratory training, active video games     

Validity and Reliability of the 3-Day Physical Activity Recall in Singaporean Adolescents

This study aimed at determining the amount of Italian television coverage dedicated to men's and women's sport and the number of male and female viewers during the 2004 Summer Olympic Games. AUDITEL-AGB Nielsen Media Research Italia provided the TV airtime data for the sport events broadcast, which were classified into three categories: men-only, women-only, and mixed-gender. The viewer sample was divided by age and gender and included three audience parameters: mean audience, share, and appreciation index. The last item is calculated from the program duration, audience permanence, and the share related to programs broadcast by other Italian channels. In particular, the appreciation index was used to investigate the relationship between (a) the viewer's and sport participants' gender and (b) the effect of Italian participation and expectations for sport achievement. The data showed that Italian male athletes outnumbered their female counterparts. Women's sport was allotted significantly less airtime than men's sport, but this imbalance was not proportional to the gender difference in the overall athletes' participation in the Games. Although the female audience represented 45% of the total, a significantly higher male mean audience and share were found. On the other hand, the appreciation of men's and women's sport events was balanced after equating for differences in media coverage. Moreover, sport achievement might have a positive effect on the trend toward equality of gender coverage, indicating that a global multisport event such as the Olympic Games is central to communicating a national image and identity independently of the athletes' gender.     

Variability of Physical Activity Patterns by Type of Day and Season in 8-10-Year-Old Boys

Abstract

The purposes of this study were to generate correction equations for self-reported height and weight quartiles and to test the accuracy of the body mass index (BMI) classification based on corrected self-reported height and weight among 739 male and 434 female college students. The BMIqc (from height and weight quartile-specific, corrected self-reported measurements) provided a more accurate estimation of BMI classification than BMIc (from corrected self-reported measurements) and BMIs (from self-reported measurements) by showing a greater ability to predict cases with either a high or a low BMI category while still maintaining a high specificity. However, the equations are applicable only to Caucasian college student populations, so cross-validation in similar populations is needed before they are used more broadly.     

早期运动疗法对急性脑梗死偏瘫患者肌力恢复的治疗作用

目的 :分析探讨早期运动疗法对急性脑梗死偏瘫患者肌力恢复的治疗作用。方法 :把 40例急性脑梗死偏瘫患者随机分为早期运动治疗组与对照组 ,早期运动治疗组 2 0例 ,在发病后接受常规药物治疗 ,病情稳定后的 7天左右在常规药物治疗的基础上进行运动疗法治疗 ;对照组 2 0例 ,在发病后接受常规药物治疗 ,病情稳定后的 2 0天左右在常规药物治疗的基础上进行运动疗法治疗。瘫痪肢体的肌力检查按LovettⅥ级分类法〔2〕。结果 :两组患者经过治疗 ,瘫痪肢体肌力都有明显的提高且早期运动治疗组肌力的提高明显高于对照组 (P <0 .0 1 )。结论 :运动疗法对急性脑梗死偏瘫患者肌力的恢复具有明显的作用 ,早期运动疗法是提高患者肌力、降低致残率、提高生活质量的较好的治疗方法     

Computerized Agility Training Improves Change-of-Direction and Balance Performance Independently of Footwear in Young Adults

Understanding the effects of training in different footwear on sporting performance would be useful to coaches and athletes. Purpose: This study compared the effects of computerized agility training using 3 types of footwear on change-of-direction and balance performance in young adults. Method: Thirty recreationally active young adults (M_age = 22.8 ± 3.1 years; M_height = 1.71 ± 0.7 m; M_bodymass = 73.4 ± 10.3 kg) were randomly assigned to a 6-week computerized agility training intervention in 1 of 3 footwear groups (n = 10/group): barefoot, minimal footwear, or traditional shoes. Participants had no previous barefoot or minimal-footwear training experience. Dependent variables included change-of-direction test time to completion, Star Excursion Balance Test, and single-leg stability evaluation. Testing was performed at the start of the training program, after 2 weeks, after 4 weeks, and at the end of the training program. Results: No group or time interactions were found for any of the dependent variables. Time main effects were observed for the performance measures of change of direction, Star Excursion, and single-leg-with-eyes-open stability evaluation. Participants improved in all 3 tests as early as 2 weeks into the intervention, with improvements continuing through the entire 6-week intervention. Conclusions: The lack of interaction and footwear effects suggests that agility and balance improvements during foot agility training are independent of footwear in a recreationally active young-adult population. Computerized agility training improves change-of-direction and balance performance within 2 weeks of training implementation. Future studies should consider footwear training effects in different populations, including frail older adults and athletes.     

早期介入运动疗法对脑出血患者肢体功能恢复的治疗作用

文章分析探讨早期运动疗法对脑出血患者的治疗作用,结果显示:运动疗法对脑出血患者的瘫痪肢体肌力的恢复具有明显的作用,对脑出血患者的运动功能及ADL能力有显著提高。早期运动疗法是提高患者肌力、运动能力、ADL能力、降低致残率、提高生活质量的较好的治疗方法。     

Effects of Aerobic Exercise on Cognitive Performance Among Young Adults in a Higher Education Setting

Purpose: Acute benefits of aerobic exercise on executive functioning have been reported frequently under laboratory conditions. However, to date, a beneficial effect on long-term memory has been less well supported and no data are available regarding nonlaboratory conditions in young adults. The aim of the current study was to investigate acute effects of aerobic exercise on cognitive functioning in a university classroom setting. Method: Using a cross-over design, 51 participants performed a bout of moderately intense running (RUN) and read an article while seated (CON). Afterwards, they completed free-recall tests, followed by a Flanker task and an n-back task. Results: Participants in the RUN condition compared with those in the CON condition showed shorter reaction time on the inhibition task, F(1, 50) = 5.59, p = .022, η² = .101, and recalled more words in the immediate- and delayed-recall tests, F(1, 50) = 8.40, p = .006, η² = .144. Conclusion: The present findings suggest that a moderately intense bout of aerobic exercise benefits verbal short-term and long-term memory as well as inhibitory control among students in a classroom setting.     

Decreasing Internal Focus of Attention Improves Postural Control During Quiet Standing in Young Healthy Adults

This experiment was designed to investigate whether and how decreasing the amount of attentional focus invested in postural control could affect bipedal postural control. Twelve participants were asked to stand upright as immobile as possible on a force platform in one control condition and one cognitive condition. In the latter condition, they performed a short-term digit-span memory task. Decreased center-of-gravity displacements and decreased center-of-foot-pressure displacements minus center-of-gravity displacements were observed in the cognitive condition relative to the control condition. These results suggest that shifting the attentional focus away from postural control by executing a concurrent attention-demanding task could increase postural performance and postural efficiency.     

Trampoline Versus Resistance Training in Young Adults: Effects on Knee Muscles Strength and Balance

ABSTRACT

Purpose: Trampoline parks are becoming popular in many countries, providing recreational facilities for children and adults. This study investigated the effects of trampoline training on knee muscles strength and balance in young adults. Methods: Twenty-six participants (14 males, 12 females) were randomized into trampoline training (TT) and resistance training (RT) groups to undergo a 6-week supervised intervention program (2 × 30 min per week). TT group performed basic trampoline exercises while the RT group performed resistance training targeting lower extremities muscles. Peak knee extension and flexion torque, postural sway characteristics, and Y balance test (YBT) performance were evaluated before and after the intervention. A mixed model analysis of variance (group × time) was applied. Results: After training there were significant improvements in knee extension torque (mean difference_post-pre [95% CI], TT: 0.27 [0.00, 0.54] N?m/kg, RT: 0.31 [0.09,0.54] N?m/kg, p = .001), knee flexion torque (TT: 0.25 [0.17,0.33] N?m/kg, RT: 0.21 [0.08,0.34] N?m/kg, p < .001), and dynamic balance (YBT composite scores, mean difference_post-pre [95% CI], TT: 4.9 [?0.3, 10.2]%, RT: 5.2 [2.4,8.0]%, p = .001). No difference between groups was found. Conclusion: Trampoline training can be as effective as resistance training for improving knee muscles strength and dynamic balance in young men and women.     

Self-Efficacy for Coping With Barriers Helps Students Stay Physically Active During Transition to Their First Year at a University

The present study examined undergraduate students' physical activity during transition from high school to first-year university. Students' (N = 127) self-efficacy for coping with barriers to physical activity was investigated both as a predictor of physical activity and mediator of the relationship between pretransition and first-year physical activity. Physical activity was found to track moderately from pretransition to first year (r _s = .58). Self-efficacy for coping with barriers predicted physical activity (R ² _adjusted = .18, p < .05) and partially mediated the relationship between pretransition and first-year physical activity. Results support an interpretation that future intervention efforts could target first-year students' self-efficacy for coping with barriers to help curb the decline in physical activity that occurs during the transition to university life.