Q I love doing HIIT sessions, but sometimes they leave me feeling burnt out. Is there a ‘right’ amount?
It’s true that HIIT (a catch-all term for training that features intense bursts of work alternated with periods of recovery) is very, very good for you, counting fat-burning and increasing your oxygen consumption among its many accolades. But HIIT sessions are only as good as your ability to recover from them; thanks to their cortisoltriggering effect, a Hiit-heavy week can lead to an excess of the hormone in your body. ‘Key to making HIIT work for you is to mix it up with different modalities,’ says Kim Ngo, pointing to an exercise week that features strength training and yoga alongside the HIIT sessions you love. Estimations on the optimum amount of HIIT vary, but recent research suggests that it should make up 4% to 9% of your total training volume. For Ngo, key to finding your personal limit is listening to your body. ‘There’s no “right” number of sessions, as it can vary from week to week, depending on everything else that’s going on in your life,’ she says, referring to everything from the time your head hit the pillow last night to that report you need to write for your boss next week. Her advice? Keep an eye on how overloaded you are outside of the gym before trying to go hard inside, then adjust your workout week accordingly. Aiming for even 10 minutes a day is a win in her book.