In this study the effects of a 6 week spinning cycling training on the body composition of women were investigated. Twelve sedentary women (32-47 years old) voluntarily participated in this study. The 6-week training program consisted of exercise sessions on 3 days per week. The intensity of the training program that was kept low in the beginning was increased in the subsequent weeks. The training sessions including the warm-up and cool down lasted for 30-60 minutes. The analyses on the body compositions were measured regularly every week with bioelectrical impedance method. In data analysis descriptive statistics and repeated-measures analysis of variance were used. In the end of the 6-week spinning workouts positive changes were observed in many parameters related to body composition. Particularly after the 3rd week the significant changes recorded were noteworthy. At the end of the 6th week those who were overweight by World Health Organization (WHO) standards moved onto normal weight category and those who were obese became overweight. In conclusion it was seen that the spinning cycling workouts were seen as as effective method to lose weight and reduce the body fat ratio among women in this age group. This exercise method may be recommended for getting good results among obese and overweight women in a short period of time.