The Grapevine

Are HIIT Workouts Safe? 4 Precautions You Should Know

High-Intensity Interval Training (HIIT) swiftly rose to popularity in recent years, ranking as the number one fitness trend of 2018 in a global survey.

While the benefits are high, it is also quite common to see people making mistakes with this form of training. Here are some precautions to keep in mind to avoid injuries and gain the best possible results:

1. Don't jump right into it

If your routine has been fairly sedentary for a long period or only included mild forms of exercise, jumping right into HIIT is not advised. "Beginning with HIIT may increase the chance for injury and muscle soreness," stated Dr. Len Kravitz and Professor Micah Zuhl in their research on endurance training. "A better approach would be to start with continuous aerobic exercise at a low-intensity level."

It was recommended that a person can take up interval training once they are able to run for 30 consecutive minutes at a moderate intensity.

2. Stay hydrated and eat right

Trainers have noted that HIIT is the one workout which can be very difficult to do without energy from carbs. The American Council on Exercise encourages a meal with protein and moderate to high levels of carbohydrate about three hours before the workout. (For example, try a wholemeal toast with peanut butter topped with sliced bananas.)

Remember to drink water as dehydration can affect your physical performance. However, sugary electrolyte drinks are best avoided according to fitness instructor Erica Stenz of Barry's Bootcamp

"You don't need a Gatorade for a 60-minute class," she said. "You're just consuming the sugar and calories that you are burning!"

3. Ensure your form is correct

Laura Miranda, a doctor of physical therapy and trainer, believed improper form to be the main cause of injury. The nature of HIIT workouts may not allow a person to slow down even as they begin to feel tired. 

"The person is then forced to then continue with the same load or exercise, cranking out the remainder reps with sloppy form in this extremely fatigued state, thus setting the stage for injury," she explained. To counter this risk, an experienced instructor can guide you to use less-demanding alternatives when your body needs to refuel. 

4. Set limits, don't overtrain

The whole point of HIIT workouts is to gain more fitness benefits by investing lesser time. In other words, doing multiple sessions a day or performing the workout five to six times a week will do more harm than good.

"When doing HIIT, you’re putting your body in 'fight-or-flight mode,' which can elevate your stress hormones," said Monica Lam-Feist, an ACE-certified personal trainer.

Overtraining can lead to strained joints, poor sleep, increased risk of injury and fatigue. Ideally, experts recommend performing HIIT workout for two to three days a week to allow for adequate recovery in between.