| Objective The aim of this paper was to compare the effects of 8-week high-intensity interval training (HIIT) on bone mineral density, bone metabolism, and physical fitness in normal weight and overweight female college students. Methods Participants were divided into two groups based on their body mass index (BMI), a normal weight group (NW, n=12) and an overweight group (OW, n=10). Total training program was designed for 8 weeks, 3 sessions per week on cycle ergometer. Each training session consisted of six repetitions of 3-min cycling at 85~90% VO2peak interspersed by periods of active recovery of 2-min cycling at 35~45% VO2peak. All participants were examined for blood parameters of bone metabolism including serum osteocalcin, 25(OH)D, calcin and, phosphorus, bone mineral density and physical fitness including VO2peak, quadrant jump in ten second, standing broad jump and 400-meter running at the pre-training and the end of the training. Results ①Compared with pre-training, the body fat percentage, fat mass, fat mass in Android region and Gynoid region of NW group and OW group were all lower after 8-week training (P<0.05). BMI, waist circumference and waist-to-height ratio were only significantly lower in OW group than pre-training (P<0.05); ②Compared with pre-training, 25(OH)D showed a dramatical improvement in both groups (P<0.01); ③Compared with pre-training, the 10-second quadrant jump, standing long jump, and 400-meter running performance were significantly improved in both groups (P<0.05); VO2peak was only significantly increased in NW group (P<0.05), and there was an interaction effect between two groups (P<0.05). Conclusion 8-week high-intensity interval training is easy to improve the body shape of overweight female college students, but it is easier to increase the femoral bone density of normal-weight female college students and improve their cardiorespiratory fitness. |