If you’re strapped for time, you may want to add high intensity interval training (HIIT) to your workout arsenal. Learn how to HIIT it without getting waylaid by injuries or burnout.
High intensity interval training (HIIT) is one of the latest fitness godsends in our hectic lives: you can lose weight, build muscle, and boost your metabolism in less time than with continuous exercise. But do you know how to stay safe during these high-octane workouts?
What is HIIT?
Typically, HIIT consists of repeated short bursts of vigorous activity that last from a few seconds to a couple of minutes, interspersed with regular recovery intervals. You can apply HIIT to running, rowing, cycling—or doing any other form of exercise.
The recovery periods allow for more spurts of high intensity effort, leading to a highly efficient workout. An effective HIIT session can take just 10 to 30 minutes. And the calorie count keeps rising even after your workout, as your body requires more energy to recover from HIIT than from traditional exercise.
The latest on the HIIT gender gap
Recent research investigating gender differences in the benefits of HIIT yielded mixed results. In a 2013 study, women doing treadmill HIIT workouts chose a more strenuous pace than men and needed less recovery time.
On the other hand, research on men and women performing cycling sprint intervals in a 2014 study revealed that only men in the study improved their exercise performance during timed trials after nine sessions of HIIT.
According to 2015 research, HIIT may benefit older men in particular. After six weeks of HIIT, older males experienced a reduction in body fat percentage and an increase in fitness levels. Meanwhile, older women saw no changes.
Practising safety first
“HIIT is becoming much more popular now, and we simply don’t have hard evidence on the safety risks,” says Jonathan P. Little, an exercise physiologist at the University of British Columbia’s Okanagan campus.
However, Little explains, we do know that the risk of a cardiovascular event may rise with the intensity of exercise. While the benefits of exercise outweigh these slight risks, take the following steps to achieve a safer HIIT workout.
Enlist professional help
If you have a personal or family history of heart disease, clear all exercise plans with your health care practitioner. You can also consult a trainer for advice on technique and form. Incorrect form, especially during high-paced workouts, is often the cause of exercise-induced injuries.
Start with a strong base
HIIT isn’t for beginners. Build a fitness base with three to six months of regular exercise, which greatly reduces your risk of cardiovascular problems due to vigorous exercise. Before trying HIIT, you should be able to work out at 85 percent of your maximum heart rate for at least 20 minutes without feeling exhausted.
What does high intensity actually mean?
One way to gauge exercise intensity is by measuring your heart rate. In general, high intensity exercise means working out at 70 to 85 percent of your maximum heart rate. To calculate your maximum heart rate, simply subtract your age from 220.
Ease into the workout
To prime your body for powerful HIIT moves, use dynamic stretches such as butt kicks or alternating reverse lunges. “Static stretching, like you would in a relaxation class or yoga pose, reduces power output to a muscle,” says Margaret Martin, an Ottawa-based physiotherapist.
In addition, warm up with five minutes of easy exercise whenever you perform HIIT. Don’t go for the gusto your first time out. Little suggests starting at four sequences of high intensity and rest intervals. Build your stamina by adding another sequence each week until you reach your goal. “Try for 30 to 60 seconds ‘on’ with 60 seconds of rest in between,” says Little.
Avoiding HIIT burnout
To obtain maximum benefits, you might be tempted to practise HIIT every time you set foot in the gym. However, HIIT should be performed only one to two times weekly as a complement to your training.
“You can overdo it,” says Toronto-based personal trainer Barb Gormley. “You can become injured, over train, or start to get a detraining effect.”
Your body will tell you when it’s reached HIIT overload: your fitness level may start going down instead of up. Further signs of burnout, according to Gormley, include
- sustaining an injury
- experiencing a lack of coordination during workouts
- feeling exhausted rather than exhilarated immediately after you work out
- feeling exhausted upon waking up the next morning
To avoid these issues, incorporate the following training tips.
Rethink your intervals
“One common mistake is having the recovery intervals too short during HIIT,” says Gormley. To remedy this, ensure your recovery intervals match or exceed your high intensity intervals.
If you opt for a 1:1 ratio of high to low intensity exercise, for example, you might run for three minutes and walk for three minutes. Beginners should start with a gentler 1:3 or 1:4 ratio of high to low intensity activity.
Common HIIT sideliners
HIIT is often performed using running, hill climbing, cycling, or rowing, which can lead to a variety of lower body injuries from muscle strains to plantar fasciitis to IT band irritation. Hip and back injuries are also common.
Using incorrect form or neglecting to build your body up to HIIT is often the culprit. “During HIIT, there’s a lot of loading on feet, knees, and hips,” says physiotherapist Margaret Martin. “If your form is compromised, it’s only going to become worse as you get fatigued.”
HIIT it your way
HIIT doesn’t have to entail an all-out sprint. You can tailor HIIT to your fitness level and incorporate it into your existing routine. For example, if your walking routine has plateaued, quicken your step as you climb hills or when you’re between light posts.
“HIIT can mean a lot of different things. If for you that’s 15 to 30 seconds of picking up the pace, then that can be a HIIT workout,” says exercise physiologist Jonathan P. Little.
Fuel up properly
Drink plenty of water after HIIT, along with some protein to aid in recovery. You might also want to incorporate a creatine supplement, which has been shown to increase endurance in high intensity exercisers.
Get your rest
Be sure to insert a rest day between HIIT workouts. “The saying is: you don’t get stronger during your workouts. You get stronger when your body is recovering, resting, and rebuilding on the rest days,” says Gormley.
Nevertheless, once you’ve built your HIIT stamina, train consistently to avoid a detraining effect. Detraining is the decline in fitness level that may happen if you stop exercising for as little as two weeks.
“If you’re going to do something intense, that’s great! Build up to it, and then stay at it,” says Martin.
Alexa Everett
Adam Meyer
Emilie Richardson-Dupuis