Leg strength
When programming a HIIT session, the main focus usually is on the cardiorespiratory adaptations that this form of training can elicit [Given the nature of the training (many repetitions with high intensity), it is possible that other aspects of physical performance were also improved, such as local muscle endurance or lactate tolerance. However, we were limited concerning the number of strenuous tests that we could include, so this remains to be tested in future studies. There are studies though that did include tests of this nature and have found positive results. For instance, McRae et al. assessed leg extension muscular endurance with as many repetitions as possible and reported an increase of 40% after 4 weeks of training [