HIIT it hard with high-intensity interval training

Performed properly, high intensity interval training (HIIT)—in which more repetitions of an exercise are done in less time, combined with rest periods—can result in improved heart function, substantial fat loss and improved blood glucose levels.

But is it for everyone? The answer is yes, but only to a degree.

The International Sports Sciences Association (ISSA) says the gains from HIIT will be more evident among untrained individuals than athletes; however, untrained individuals are more likely to suffer muscle strain from working out at a higher intensity.

Additionally, HIIT will not improve the ability of practitioners in long distance or duration endurance events.

Most experts suggest that more than two sessions per week are necessary for improving performance without causing excessive stress, and Stephen Seiler, considered to be one of the world’s foremost experts in the practical use of HIIT, says more than two sessions per week have no added benefit and amplify the likelihood of injury due to muscle strain.

ISSA also suggests that for conditioning and fat loss, you should pick an endurance exercise; establish a baseline that can be sustained for 30 to 60 minutes and start with a work-to-rest ratio of one-to-one minutes, eventually building to three or four minutes with one minute of rest.

For resistance circuit training intervals for strength endurance and fat loss, ISSA suggests picking three to five full-body exercises that can be executed with good form; keep the total reps of each exercise under 75; and rest 30 to 60 seconds after every one-two minute set.