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171.
Abstract

Pedometers have been identified as a tool for health professionals to promote physical activity. This study, which aimed to evaluate the effectiveness of wearing a pedometer on general practitioners' attitudes to promoting physical activity, was a pragmatic, multi-centred, randomized controlled trial within a primary care trust in England. The participants were 102 general practitioners (GPs). Eighty-five (48 males, 37 females) of the GPs completed pre and post questionnaires, 43 of whom were in the intervention group. Statistical analysis revealed no significant changes between the control and intervention groups for attitude to engage in physical activity (t 83 = 1.13, CI ?0.362 to 0.099) or attitude to promote physical activity in their patients (t 83 = 1.7, CI ?0.593 to 0.045). A higher volume of walking was significantly correlated with a more positive attitude to engage in physical activity (r = 0.58, P < 0.01) but not with a more positive attitude to promoting physical activity. Wearing a pedometer had no significant effect on GPs' attitudes to engaging in physical activity or promoting physical activity in their patients.  相似文献   
172.
173.
Abstract

An experimental design was employed to assess the effectiveness of a relapse prevention program, a reinforcement program, and an exercise-only control group in increasing exercise program adherence and short-term maintenance in 120 previously sedentary female university employees. The subjects participated in an 18-week exercise program composed of stretching, calisthenics, and aerobic dance. Attendance during the first half of the program was significantly higher for subjects in the relapse prevention group than for those in the control group. A nonsignificant trend in this direction emerged during the second half of the program and at 2-month follow-up. For all treatment groups, attrition (attendance at less than two thirds of the exercise sessions) was substantial, averaging 72% at the end of the 18-week program. These findings indicate that relapse prevention and reinforcement programs may not assist previously sedentary females in long-term adherence to an exercise program.  相似文献   
174.
Abstract

It has been suggested in the lay literature that static stretching and/or warm-up will prevent the occurrence of Delayed-Onset Muscle Soreness (DOMS). The primary purpose of this study was to determine the effects of static stretching and!or warm-up on the level of pain associated with DOMS. Sixty-two healthy male and female volunteers were randomly assigned to four groups: (a) subjects who statically stretched the quadriceps muscle group before a step, (b) subjects who only performed a stepping warm-up, (c) subjects who both stretched and performed a stepping warm-up prior to a step test, and (d) subjects who only performed a step test. The step test (Asmussen, 1956) required subjects to do concentric work with their right leg and eccentric work with their left leg to voluntary exhaustion. Subjects rated their muscle soreness on a ratio scale from zero to six at 24-hour intervals for 5 days following the step test. A 4×2×2 ANOVA with repeated measures on legs and Duncan's New Multiple Range post-hoc test found no difference in peak muscle soreness among the groups doing the step test or for gender (p > .05). There was the expected significant difference in peak muscle soreness between eccentrically and concentrically worked legs, with the eccentrically worked leg experiencing greater muscle soreness. We concluded that static stretching and!or warm-up does not prevent DOMS resulting from exhaustive exercise.  相似文献   
175.
Abstract

It was the purpose of this investigation to conduct a program in perceptual-motor development and to determine changes in, and assess relationships between, changes in perceptual-motor development on visual perception and reading readiness of first-grade children. Four classes were equated on the variables age, height, sex, and weight. Two of the classes (experimental) were exposed to the perceptual-motor program for 12 weeks and the other two classes (control) took part in the conventional physical education program. All students participated in their regular classroom activities. All subjects were evaluated in perceptual-motor development, visual perception, and reading readiness prior to and immediately following the research program. The difference scores (pre- and post-test) were evaluated by two-way ANOVA to determine if there were any significant differences between groups. F ratios for the three variables tested were all significant beyond the .01 level in support of the perceptual-motor program.  相似文献   
176.
Abstract

The aim of the present study was to identify when body mass index (BMI) is unlikely to be a valid measure of adiposity in athletic populations and to propose a simple adjustment that will allow the BMI of athletes to reflect the adiposity normally associated with non-athletic populations. Using data from three previously published studies containing 236 athletes from seven sports and 293 age-matched controls, the association between adiposity (sum of 4 skinfold thicknesses, in millimetres) and BMI was explored using correlation, linear regression, and analysis of covariance (ANCOVA). As anticipated, there were strong positive correlations (r = 0.83 for both men and women) and slope parameters between adiposity and BMI in age-matched controls from Study 1 (all P < 0.001). The standard of sport participation reduced these associations. Of the correlations and linear-regression slope parameters between adiposity and BMI in the sports from Studies 2 and 3, although still positive in most groups, less than half of the correlations and slope parameters were statistically significant. When data from the three studies were combined, the ANCOVA identified that the BMI slope parameter of controls (5.81 mm · (kg · m?2)?1) was greater than the BMI slope parameter for sports (2.62 mm · (kg · m?2)?1) and middle-distance runners (0.94 mm · (kg · m?2)?1) (P < 0.001). Based on these contrasting associations, we calculated how the BMI of athletes can be adjusted to reflect the same adiposity associated with age-matched controls. This simple adjustment allows the BMI of athletes and non-athletes to be used with greater confidence when investigating the effect of BMI as a risk factor in epidemiological research.  相似文献   
177.
Abstract

The single-stage treadmill walking test of Ebbeling et al. is commonly used to predict maximal oxygen consumption ([Vdot]O2max) from a submaximal effort between 50% and 70% of the participant's age-predicted maximum heart rate. The purpose of this study was to determine if this submaximal test correctly predicts [Vdot]O2max at the low (50% of maximum heart rate) and high (70% of maximum heart rate) ends of the specified heart rate range for males and females aged 18 – 55 years. Each of the 34 participants completed one low-intensity and one high-intensity trial. The two trials resulted in significantly different estimates of [Vdot]O2max (low-intensity trial: mean 40.5 ml · kg?1 · min?1, s = 9.3; high-intensity trial: 47.5 ml · kg?1 · min?1, s = 8.8; P < 0.01). A subset of 22 participants concluded their second trial with a [Vdot]O2max test (mean 47.9 ml · kg?1 · min?1, s = 8.9). The low-intensity trial underestimated (mean difference = ?3.5 ml · kg?1 · min?1; 95% CI = ?6.4 to ?0.6 ml · kg?1 · min?1; P = 0.02) and the high-intensity trial overestimated (mean difference = 3.5 ml · kg?1 · min?1; 95% CI = 1.1 to 6.0 ml · kg?1 · min?1; P = 0.01) the measured [Vdot]O2max. The predictive validity of Ebbeling and colleagues' single-stage submaximal treadmill walking test is diminished when performed at the extremes of the specified heart rate range.  相似文献   
178.
179.
Abstract

This study analysed the first stance phase joint kinetics of three elite sprinters to improve the understanding of technique and investigate how individual differences in technique could influence the resulting levels of performance. Force (1000 Hz) and video (200 Hz) data were collected and resultant moments, power and work at the stance leg metatarsal-phalangeal (MTP), ankle, knee and hip joints were calculated. The MTP and ankle joints both exhibited resultant plantarflexor moments throughout stance. Whilst the ankle joint generated up to four times more energy than it absorbed, the MTP joint was primarily an energy absorber. Knee extensor resultant moments and power were produced throughout the majority of stance, and the best-performing sprinter generated double and four times the amount of knee joint energy compared to the other two sprinters. The hip joint extended throughout stance. Positive hip extensor energy was generated during early stance before energy was absorbed at the hip as the resultant moment became flexor-dominant towards toe-off. The generation of energy at the ankle appears to be of greater importance than in later phases of a sprint, whilst knee joint energy generation may be vital for early acceleration and is potentially facilitated by favourable kinematics at touchdown.  相似文献   
180.
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