No, it’s not magic or some loop hole. In its current guidelines, the HSS recommends an alternative to cardio: 75 minutes of vigorous aerobic exercise. Many things can fall under this umbrella, but quick HIIT workouts are one of the easiest options because they’re most effective when they’re short. “You can’t act at one the truth If high intensity [the workout] long,” Rachel Vajiralli, Equinox’s group fitness creative manager and exercise-science expert previously told Well+Good.
There’s a lot to love about high-intensity interval training, a form of exercise that fast-tracks your physical activity goals. But an unexpected benefit of HIIT is how it affects your hormones, especially cortisol, the hormone our bodies release when we’re under stress, and how less high-intensity cardio can help lower its levels compared to low-to-moderate levels. can Aerobic exercise.
How Cutting Cardio Can Help Cut Cortisol
When we exercise, our bodies release cortisol because “exercise is basically a controlled stress on your body,” says exercise physiologist Sharon Gam, PhD, CSCS. Hormonally, our bodies respond to exercise in the same way they respond to other stressors. According to Dr. Gum, this is a perfectly healthy bodily function, until our body is able to adequately reset and return to normal levels. The way you do that is through rest and recovery.
Where a surprising benefit of high-intensity workouts comes in, HIIT and other intense exercises such as HILIT (high-intensity, low-impact training) make your body produce more cortisol than a moderate-intensity workout. But because they consume so much, then, the signal to your brain to load off your hormones is louder and clearer than the memo you get after a long period of cardio.
“What many people are doing is skipping recovery, constantly doing moderate intensity and not allowing their body to return to baseline,” says Dr. Gum. “However, when you exercise more vigorously, you become very tired, which forces you to rest afterwards.” Ideally, you should buffer at least one day between high-intensity cardio workouts to give your body time to recover. Basically, if you’re doing steady state cardio, you can have chronically elevated cortisol levels without those important rest periods, which can negatively impact your endocrine system as a whole.
It’s not just fatigue that promotes healthy recovery and lower cortisol levels after HIIT versus steady state cardio. High-intensity exercise causes your brain to release extra hormones, such as human growth hormone, which also sends signals to slow down. “It’s not activated in the medium steady state,” says Dr. Gum. “You’re getting the stress response, but not the extra tools to help your body get back to a better baseline. Whereas with higher intensity, you’re going to get a peak of stress, but you’re going to get a lot more tools to help your body rebuild later.”
So if you’re looking to go the efficient route while hitting your weekly cardio baseline—and help keep your cortisol levels at bay—here are three 25-minute HIIT workouts. Do all three in one week, and you’ll crush that 75-minute high-intensity exercise goal. Get after it!
25-minute bodyweight HIIT workout
This workout specifically targets your core and raises your heart rate with intervals that will have you sweating in no time.
Barry’s 25-Minute HIIT Cardio Workout
Barrie is known for their sprints, so this workout mimics the intensity of boot camp sprint intervals from the comfort of your home gym.
Barry’s 25-Minute Lower-Body HIIT Workout
If you want to do your squats and lunges to meet your cardio goals, this lower-body focused workout is for you.
And don’t forget to do some active recovery work!