A new bio-mechanical model for elbow flexions is proposed to quantify the elbow torque generated as a function of the upper-arm circumferential strain and influencing factors of elbow angle and angular velocity. The upper-arm circumferential strain is used to represent the contractile intensity of the dominant flexor, biceps brachii, whose behavior is described by Hill's theory. Experiments with thirteen healthy subjects were conducted to determine the influencing factors.
View Article and Find Full Text PDFBackground: Overweight, obesity, and cardiovascular disease risk factors are prevalent among firefighters in some developed countries. It is unclear whether physical activity and cardiopulmonary fitness reduce cardiovascular disease risk and the cardiovascular workload at work in firefighters. The present study investigated the relationship between leisure-time physical activity, cardiopulmonary fitness, cardiovascular disease risk factors, and cardiovascular workload at work in firefighters in Hong Kong.
View Article and Find Full Text PDFBackground And Objective: The aim of this study was to investigate the aerobic capacity of children 3 years after they were diagnosed with severe acute respiratory syndrome (SARS).
Methods: Twenty-seven patients who completed both pulmonary function and maximal aerobic capacity tests at 6 and 15 months after the acute illness were invited to return for reassessment.
Results: Twenty-one patients (median age 18.
Purpose: Wavelet transform is a time-frequency analysis method that quantifies temporal changes of the frequency content of nonstationary signals without losing resolution in time or frequency. It may be used to analyze surface EMG (sEMG) signals under dynamic conditions. However, this method is difficult to apply clinically because it generates large quantity of data in a very short time, and the change in muscle fiber length and diameter during dynamic contraction induces a large variability of the data at various wavelet domains and joint positions.
View Article and Find Full Text PDFSpecific sequences of muscle coordination exist in movements of every sport. In particular, sports involving repetitive movement patterns such as rowing may rely more heavily on coordinated muscle contraction sequencing in order to produce optimal performance. The aim of this study was to monitor the fatigue patterns of the major muscles engaged during the rowing stroke in rowers of varying abilities during a 6-minute continuous maximal rowing effort on a Concept II rowing ergometer.
View Article and Find Full Text PDFThe aim of this study was to evaluate the effect of transcutaneous electrical acupoint stimulation (TEAS) at selected acupoints on enhancing the rate of muscle force recovery after strenuous knee extension/flexion exercise. Ten male and seven female healthy young adults participated in this study in which they performed isokinetic knee fatigue exercise on the Biodex System 3 ergometer on three separate days. After the familiarization trial on day 1, subjects underwent 15 min of either TEAS or pseudo-TEAS recovery treatment after the isokinetic exercise in the following two trials on days 2 and 3, respectively.
View Article and Find Full Text PDFThe purpose of this study was to test the hypothesis that strength training benefits diet-controlled obese children with respect to lean mass and bone mineral acquisition. Eighty-two Hong Kong school children (aged 10.4 +/- 1.
View Article and Find Full Text PDFSevere Acute Respiratory Syndrome (SARS) not only paralysed economic activities in SARS-affected cities, it also affected sporting activities. SARS was identified in Hong Kong in late February 2003 and the WHO issued a global alert on 12 March, 2003. The incubation period of SARS is usually 4-6 days and patients commonly present with high fever (temperature >38 degrees C), dry cough, chills and rigor, dyspnoea and diarrhoea.
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