摘要:

To analyze the effect of inversion trauma on peroneal nerve function, motor conduction velocity was measured in 22 patients. In the injured leg, 4–8 d post trauma motor nerve conduction velocity in the knee-caput fibulae segment of the superficial peroneal nerve was significantly smaller when compared with the contralateral leg and the control group. Five weeks post trauma these values were normal again. For three segments of the deep peroneal nerve, the motor conduction velocity was significantly reduced, 4–8 d post trauma, when compared with the control group. In the caput ankle and knee-ankle segment, motor conduction velocity was still significantly lowered 5 wk post trauma. Lowered amplitudes of the Compound Motor Action Potentials of the extensor digitorum brevis muscle were found 4–8 d post trauma. No correlation was found between motor nerve conduction velocities and subjective clinical tests (anterior drawer sign and (manually performed) talar tilt test). The results of this study support the hypothesis that inversion trauma is frequently accompanied by lesions of the peroneal nerve. Motor conduction velocity measurements can be a valuable tool in assessing more objectively functional instability of the ankle joint induced by inversion trauma.

ISSN:0195-9131    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

In this cross-sectional, retrospective study, the bone mineral content (BMC) and density (BMD) of the whole skeleton, upper limbs, lower limbs, femoral neck, and lumbar vertebrae were measured using dual photon absorptiometry and the results compared in healthy young males involved in: weight-lifting, running, cross-training, or recreational exercises. When adjusted for body weight, the upper limb BMD was highest in those engaged solely in weight-lifting, (mean 1.021, SE 0.019, and 95% CI 0.981–1.061) and lowest in runners (mean 0.908, SE 0.019 and 95% CI 0.869–0.946). These differences were significant (P= 0.0004). There were no significant differences in upper limb BMD between weight-lifters and cross-trained athletes and between runners and those engaged in recreational exercises. Significant differences in BMD were observed between weight-lifters and recreational athletes (P= 0.001) and between cross-trained athletes and runners (P= 0.03). No other significant differences were observed. These data suggest that healthy, young, adult males reporting a history of intensive weight-lifting had significantly greater bone mass of the upper limb bones than those reporting a history of non-weight-lifting exercises. These results imply a specific versus generalized effect of mechanical load on bones of the skeleton.

ISSN:0195-9131    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

We studied theinterrelations between, on the one hand, the physical activity (frequency, duration, intensity, and mode) measured by a questionnaire and, on the other, &OV0312;O2max(submaximal bicycle ergometer test) and the explosive muscle strength (vertical jumping height). A random sample of 774 health subjects from the city of turku participated in this study; the subjects were 25, 35, 45, or 55 yr of age. The &OV0312;O3maxof physically active 55-yr-old female subjects was on the same average level as of 25-yr-old females, who were physically inactive. Correspondingly, the average &OV0312;Omaxof physically active 55-yr-old males, who were physically inactive. With the exception of the oldest female study group, the jumpcing test of physically active subjects gave similar results as those of their inactive counterparts who were 10 yr younger. On the basis of the sports events reported by the subjects, we classified the subjects into five activity mode categories. The mode of activity was significantly associated with &OV0312;Omaxin a three-way anova (P= 0.0027) as well as with as with the jumping test result (P= 0.0001_. Mixed training (includes varied types fo exercise for the neuromuscular system) was the most beneficial mode of exercise for developing jumping height. The study suggests that the intensity, freqency, and duration of regular physical activity habits during leisure are associated with both &OV0312;Omaxand the jumping height, and that the jumping height results, in particular, are increased by mixed training.

ISSN:0195-9131    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Coronary heart disease (CHD) is uncommonly low among black South Africans. Although dietary and genetic influences probably contribute to their favorable serum lipid profile, other cardioprotective factors may also play a significant role in explaining the low incidence of CHD. From a socioeconomic perspective, it appears that the black community engages in regular physical activity (PA) more so than other populations. Since data are lacking, our aim was to provide preliminary data on the association between PA and the traditional CHD risk factors. The sample consisted of 212 working, middle-aged men drawn from an epidemiological database on the African population of metropolitan Cape Town. Analysis of responses to basic questions on PA behavior indicated i) 43% of the sample were employed in jobs requiring moderate to strenuous PA, and ii) the most favorable blood pressure and serum lipid profiles were associated with low to moderate levels of habitual exercise. As this community becomes more urbanized, job-related PA as well as PA of daily living will decline. The need for sports and leisure-time PA programs will become more important and should be considered as part of a public health strategic plan.

ISSN:0195-9131    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

To determine whether exercise duration effects the recovery sleep following exercise, eight fit male endurance athletes, ages 23–42 yr, had their sleep electrophysiologically studied. This was done on four separate occasions: after a day on which no specific exercise was performed; after a day of a 15-km run; after a 42.2-km run day; after a day in which the athletes participated in a strenuous ultra-triathlon. Sleep patterns following the no exercise day and the 15-km and the 42.2-km run days were similar. The sleep pattern of the ultra-triathlon day when compared with the other three days showed significantly increased wakefulness and delayed and decreased rapid eye movement (REM) sleep. The duration of slow wave sleep (SWS) in the first 6 h after lights out, however, was no different. The increased wakefulness and decreased REM clearly indicate increased stress after the ultra-triathlon. REM sleep appears to be a more sensitive index of exercise induced stress than SWS.

ISSN:0195-9131    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Many research studies report the long-lasting elevation of metabolism following exercise. However, little is known regarding the impact of duration and intensity on this phenomenon, particularly in trained women in whom the time of the menstrual cycle has been controlled. This study examined the effects of a constant walking intensity (70% of maximal oxygen uptake (VO2max)) on the treadmill at various levels of duration (20, 40, and 60 min) on 3-h recovery of oxygen uptake (VO2). Eight trained (mean ± SD) (VO2max= 47.6 ± 3.2 ml·kg−1·min−1) females (mean age = 30.2 ± 5.0 yr, mean weight = 58.7 ± 7.6 kg, mean height = 165.6 ± 7.0 cm) participated in the study. Subjects reported to the lab for a maximal oxygen consumption test and returned on four additional occasions (control, 20, 40, 60 min) in random fashion. Treadmill speed and grade were established to yield the appropriate intensity for each subject. Following each exercise bout subjects sat quietly for a 3-h time period. Variables measured included VO2, minute ventilation (VE), respiratory exchange ratio (RER), heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and core (rectal) temperature (Tc). Variables were measured each 15 min of recovery. An ANOVA was used to assess differences due to duration. Excess postexercise oxygen consumption (EPOC) was calculated by subtracting the resting VO2from the absolute VO2and summing the individual EPOCs during each 3-h postexercise session and comparing these individual values to the preexercise VO2values. The EPOC was significantly elevated (P< 0.05) in each of the three durations as compared with the control (sitting) and preexercise periods. The total EPOC was significantly higher for the 60-min duration (15.2 1) as compared with either 20-min (8.6 1) or 40-min (9.8 1) duration (P< 0.05). This was observed without significant changes in VE, RER, HR, SBP, DBP, or Tc. Additionally, there were no differences during exercise across the three durations in VO2, VE, RER, HR, SBP, DBP, or Tc. These data suggest that exercise duration increases EPOC significantly and that a 60-min duration yields approximately twice the EPOC than either 20 or 40 min.

ISSN:0195-9131    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

The limitation of aerobic exercise capacity of athletes with the sickle cell trait (SCT), under conditions of limited oxygen availability, is still controversial. To study this, we took advantage of an unique setting, the International Mount Cameroon Ascent Race, a 34.1-km race over difficult terrain, slopes ranging from 7 to 40%, and altitudes varying from 615 to 4095 m, combined with high prevalence rates of SCT among the African runners. Of 266 Cameroonian runners, SCT was detected in 33 athletes (12.4%), a prevalence similar to that of the ethnically corrected general population. However, in runners of the Bakoueri tribe whose performance is contingent with social stature, SCT was present in only 1 of 41 runners (2.4%), as compared with 15.6% in the general population of the Bakoueri tribe (P< 0.03). In general, performance times of SCT runners were not different from non-SCT runners, except during the portion of the race at altitudes ranging from 3800 to 4095 m, where significantly longer times were clocked by SCT subjects (P< 0.02). We conclude that prolonged aerobic efforts in hypobaric hypoxic conditions may be associated with a detrimental effect on performance in SCT carriers. If this is true, it might account for the reduced prevalence of SCT among those runners representing the Bakoueri tribe, provided an objective measure of performance at altitude was employed to select these representatives.

ISSN:0195-9131    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

The Pearson product-moment correlation has been used by researchers to compare time series data sets to assess the temporal similarities. Computer generated data, vertical ground reaction force (VGRF) data and hybrid data (constructed by combining features of computer generated and VGRF data) were used to investigate the influence of timing and amplitude differences on the effectiveness of this technique. Under a specific set of conditions the correlation coefficient is a valid and reliable indicator of temporal similarity. Deviations from these conditions, however, result in interactive effects between timing and amplitude components with subsequent reductions in the value of the coefficient. Although GRF data were evaluated, the results apply equally to other types of curves as well. The correlation coefficient is easy to use and can be used to evaluate the entire curve as opposed to discrete data points. Its usefulness is jeopardized, however, since it can be influenced by timing and amplitude differences as well as the characteristics of the curves being analyzed. A high coefficient is always indicative of temporal similarity but a lesser value does not guarantee a lack of temporal similarity.

ISSN:0195-9131    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

The past 10–15 yr have witnessed a rapid increase in the development of new (and not so new) statistical methods that capitalize on recent advances in highspeed computing. These computer-intensive methods are often broadly referred to as resampling techniques and take several forms depending on the specific details of the procedure and the information of interest. Resampling techniques can be used both for inferential hypothesis testing as well as exploratory data description. Regardless of which method is employed, the central unifying theme is based upon the computer's power to rapidly resample many pseudosamples from a known (in-hand) data set (e.g., randomization tests, jackknife, bootstrap, cross-validation) or to randomly generate many pseudosamples from a theoretical probability distribution (e.g., normal, binomial, Poisson) with some known parameters (Monte Carlo method). This paper is not intended as a detailed description of computer-intensive methods, but only as an introduction to the resampling approach in cross-validation. A brief discussion of the motivation and an example in an exercise science context will be presented.

ISSN:0195-9131    

出版商:OVID    

年代:1994

数据来源: OVID

ISSN:0195-9131    

出版商:OVID    

年代:1994

数据来源: OVID