The effect of a very-low-calorie diet with and without chronic exercise on thyroid and sex hormones, plasma proteins, oxygen uptake, insulin and c peptide concentrations in obese women.

It is concluded that during a short period of VLCD exercise did not produce a higher body weight loss nor a protective effect on lean body mass.

Abstract

In 18 obese women a very-low-calorie diet (VLCD) has been combined with exercise (three times a week = 1650 kcal/week; 6.9 MJ) and compared with the effects of diet alone. The adherence and tolerance of the diet was quite good. Oxygen uptake decreased significantly only in the exercising group. Sex hormones binding globulin increased while prealbumin and retinol binding protein decreased in both groups. Changes in T4, T3, rT3, TSH, TBG and insulin secretion appeared to be equal in both groups. No significant differences between the two groups have been found with respect to body weight, body fat and lean body mass loss. Glucose tolerance deteriorated in the diet only group but remained unchanged in the group combining diet and exercise. Insulin production after oral glucose load did not change in either of the two groups. A more pronounced decrease in c peptide concentration has been observed in exercising groups. Sex hormones binding globulin and testosterone concentration increased in both groups. No changes have been detected in the concentration of transcortin. It is concluded that during a short period of VLCD exercise did not produce a higher body weight loss nor a protective effect on lean body mass.