Die invloed van inoefeningsprogramfrekwensie tydens fisieke herkondisionering op enkele fisieke, biochemiese en hemodinamiese parameters

Abstract

RESEARCH PROBLEM In the practice of biokinetics, training programmes often have to be interrupted, leading to physical deconditioning. Little research has been done on the influence of previous training programmes on reconditioning by means of regular exercise after a period of inactivity ( deconditioning), or on the influence of programme frequency. These problems are highly relevant, since biokineticists are constantly confronted with them. The aim of this study was to investigate the influence of programme frequency during physical reconditioning. 2. METHOD OF RESEARCH To achieve the above-mentioned objective, data obtained from a survey undertaken by the Biokinetics centre of the Department of Human Movement Science at the University of the North were analysed. Data were obtained from a stratified non-randomized sample of 60 white males between the ages 29 and 49, employed at the above-mentioned university. The sample was divided into an experimental and a control group, with the experimental gro~p being further subdivided into two (Experimental Groups A and B). The experimental group underwent a programme of physical training, detraining and retraining, each phase lasting 12 weeks. In the training phase, both experimental groups trained at a frequency of 3 sessions a week. In the retraining phase, group A trained at a frequency of 2 sessions a week and group B at 4 sessions a week. The control group continued with their normal lifestyle without undergoing any training programme. At the end of each phase, all groups were evaluated. The sequence of the physical assessment was as follows: measurements of biochemical parameters, stature, body mass, body fat, heart rate, and blood pressure at rest, physical work capacity - including exercise blood pressure - and systolic time intervals. 3. RESULTS The following results were found: 3.1 Retraining at a frequency of 4 sessions per week occurred significantly faster than with 2 sessions a week in the case of physical work capacity, pre-ejection period/workload-ratio, (PEP-I/W-ratio) and left ventricular ejection time/workload-ratio (LYET-I/W-ratio), but not in the case of body composition, blood lipids (total cholesterol, HDL-C, LDL-C, triglycerides, TC/HDL-ratio, systolic and diastolic blood pressure (rest), systolic and diastolic blood pressure/workload-ratio, double product (rest), double product/workload-ratio, PEP-I (rest), PEP-I/W-ratio, isovolumetric contraction time (rest), isovolumetric contraction time/ workload-ratio (IYCT/W-ratio), LVET-I (rest), LVET-I/W-ratio, PEP/ LVET-ratio (rest and recovery). 3.2 Retraining at a rate of 2 sessions per week produced significant reductions in the percentage of body fat as well as significant improvements in the total cholesterol, TC/HDL-ratio, LDL-C, triglycerides, HDL-C, diastolic blood pressure (rest), diastolic blood pressure/workload-ratio, but no change in physical work capacity, systolic blood pressure/workload-ratio, L VET-1/W-ratio, PEP /L VET-ratio. 3.3 Retraining at 4 sessions per week proceeded significantly faster than training at 3 sessions a week when physical work capacity, total cholesterol;"'HDL-C, TC/HDL-ratio, LDL-C, triglycerides, do,uble product/ workload-ratio, PEP-1/W-ratio and PEP/LVET-ratio were considered. In the case of body composition, systolic and diastolic blood pressure (rest), double product (rest), diastolic blood pressure/workload-ratio, PEP-I (rest), PEP-I/W-ratio (recovery), LVET-I (rest), LVET-I/W-ratio (recovery), no significant difference occurred between the rate of retraining at 4 sessions a week and training at 3 sessions a week. 3.4 Retraining at 4 sessions per week proceeded significantly slower than training at 3 sessions a week when only the physical work capacity of subjects was considered. 3.5 Retraining at a frequency of 4 sessions per week progressed at the same rate as training at 3 sessions a week with regard to isovolumetric contraction time (rest and recovery).