This study aims to compare the women engaged in doing regular exercise and those having done exercise previously and now not doing it or never done it before in terms of such blood values as leptin, cholesterol, insulin, glucose, triglyceride levels and body fat percentage (BFP) and to investigate the effects of regular exercise on these values. The participants of the study consisted of 35 (sportswomen) women doing regular exercise and 35 healthy and sedentary female university students never involved in doing regular exercise before. With the permission of the ethics committee, measuring was made. The mean (X) age of those doing regular exercise was 18.03±0.81 years, X height was 163.62±5.28 cm, X
weight was 57.12±5.77 kg, and training background 7.34±1.75 years. X age of sedentary group was 18.91±0.72 years, X height was 164.45±5.44 cm, X weight was 58.15±4.68 kg. Statistically significant differences were found between the two groups in terms of the values of HDL and Triglyceride (p0.05). The increase in serum leptin levels is directly correlated with BFP. It has also been observed that regular exercise, as it reduces BFP, suppresses serum leptin levels. Regular exercise is significant in the regulation of body weight and prevention of obesity. It is concluded that if regular and moderate exercise is supplemented by good nutrition to avoid cardiovascular risk factor, to reduce LDL level, to bring about an increase in the level of HDL, this creates a positive influence on hormones and body fats and that exercise could be an important factor in enhancing the quality of life
