The remarkable popularity of fitness trends like high intensity functional training (HIFT), choreographed high intensity classes (CHIC) and resistance (RT) trainings raises the question on their effect on cardio-respiratory, lactate removal rate, endurance and body composition responses. The purpose of this study was to assess and compare these effects. Ninety-five participants were randomly assigned into 16 weeks of these trainings, five sessions/week. Anthropometric and fitness tests were carried out before training (PRE), after eight (8W) and sixteen weeks (16W). Body composition measures demonstrated significant decrease in body fat percentage (p<0.001, d=0.17-0.54) for all groups and fat mass (p< 0.001, d= 0.26-0.53) for HIFT and CHIC in 8W,16W and in 16W for RT (p= 0.03, d= 0.14), also significant increase in fat free mass only in HIFT (p< 0.002, d= 0.06-0.21) and RT (p< 0.001, d= 0.17-0.33) in 8W,16W. Cardio-respiratory measures demonstrated significant improvements in maximal aerobic capacity for HIFT (p< 0.001, d= 0.58-1.26) and CHIC (p< 0.001, d= 0.45-1.21) in 8W,16W. Endurance tests demonstrated significant improvements in 8W,16W in aerobic endurance among HIFT (p< 0.001, d= 1.28-3.19) and CHIC (p< 0.001, d= 1.16-1.79), in muscle absolute endurance in three groups (p< 0.002, d= 0.14-1.17)and muscle relative endurance in HIFT (p< 0.02, d= 0.13-0.2)and RT (p= 0.03, d= 0.3) in 16W. We can conclude that HIFT and CHIC are effective for cardio-respiratory and endurance improvement and all three programs are effective in reducing body fat.
Keywords: HIFT; lactate; organic responses; stamina; training.