Effect of different forms of high-intensity interval training on V̇O2max, strength, flexibility, and body fat percentage among middle-aged males.

Background: High-intensity interval training (HIIT) has become a popular exercise approach due to its potential to elicit significant physiological adaptations. However, limited research has compared the effects of different HIIT modalities on fitness parameters in middle-aged males. This study aimed to determine the effect of different HIIT on V̇O2max, strength, flexibility, and body fat percentage among middle-aged males.