EXERCISE AND WEIGHT CONTROL IN SEDENTARY OVERWEIGHT MEN - EFFECTS ON CLINIC AND AMBULATORY BLOOD-PRESSURE

Objective To examine whether restriction of caloric intake and exercis e of vigorous intensity can independently and additively influence cli nic and ambulatory blood pressures in sedentary overweight men. Design Sixty subjects aged 20-50 years were randomly allocated either to con tinue their normal caloric intake or to restrict it by 4186-6279 kJ/da y, with 15% provided by protein, 30% by fat and 55% by carbohydrate, f or 16 weeks, Within each of these groups subjects randomly allocated e ither to a control programme of exercise or to a vigorous intensity pr ogramme of exercise for 30 min three times a week The light exercise g roup performed stationary cycling against no resistance, flexibility e xercises and slow walking, The vigorous intensity group cycled on an e rgometer at 60-70% of maximum their workload. Results Fifty-one subjec ts completed the study. Their maximal oxygen uptake was increased by a pproximately 24%, with vigorous exercise but did not change with light exercise. Caloric intake restriction led to a significant loss of bod y mass of 9.5 kg (95% confidence interval 7.6-11.3), whereas vigorous exercise had no effect Restriction of caloric intake reduced supine cl inic systolic and diastolic blood pressures significantly by 5.6 (2.3- 8.9) and 2.4 mmHg (0.4-4.2), respectively. Relative to the control lig ht exercise group, exercise of vigorous intensity exercise had no sign ificant effect on clinic blood pressure, In contrast, time series anal ysis revealed that both caloric intake restriction and vigorous exerci se were associated with lower daytime ambulatory systolic blood pressu re, the reduction in systolic blood pressure being sustained throughou t the 24h period when vigorous exercise and caloric intake restriction were combined. Conclusion Compared with the effects of caloric intake restriction, the effects of a vigorous exercise programme on blood pr essure are inconsistent, there being no influence on clinic blood pres sure but a reduction in daytime ambulatory blood pressure. However, wh en combined with caloric intake restriction, regular vigorous exercise exhibits a synergistic effect in reducing ambulatory blood pressure t hroughout a 24h period.