EFFECTS OF SWIM TRAINING ON BODY-WEIGHT, CARBOHYDRATE-METABOLISM, LIPID AND LIPOPROTEIN PROFILE

The beneficial effects of regular exercise are primarily based on data using land-based exercise. Currently, no data exist that demonstrate the efficacy of swimming exercise for the treatment of obesity and car diovascular risk factors, despite the fact that swimming is a widely r ecommended exercise mode. Eighteen previously sedentary obese individu als were divided into a swim-training group and a non-exercising contr ol group. The training group swam at 60% of maximal heart rate reserve for 45 min per day for 3 days per week for 10 weeks, whereas the cont rol group remained sedentary. The swim-training programme produced sig nificant cardiovascular training effects, as evidenced by reductions ( P<0.05) in resting and submaximal heart rate values in the training gr oup. Significant reductions (P<0.05) were also observed in the rating of perceived exertion and blood lactate concentrations during fixed su bmaximal exercise on an arm cycle ergometer. Caloric and macronutrient intake estimated from the dietary records stayed constant before and after training. Body mass, body fat percentage (36+/-2% vs. 35+/-2%) a nd body mass index, as well as regional adiposity, showed no statistic ally significant changes. Neither the training nor the control groups experienced significant changes in fasting serum glucose and insulin c oncentrations and glucose-insulin ratio during the study. Total, high- density lipoprotein (HDL)- and low-density lipoprotein (LDL)-cholester ol did not change significantly in either group. It was concluded that swim training of the duration, frequency and intensity used in the pr esent study failed to elicit favourable modifications in these traditi onal cardiovascular risk factors.