If you want to work out, there's never a shortage of options out there, like dancing for cardio or teaming up with a partner. One method you'd probably heard of is interval training: short bursts of higher-intensity exercise followed by brief periods of lower-intensity exercise or rest. Many swear by it, but is the concept of shorter workouts yielding greater rewards too good to be true?
A data analysis recently published in the British Journal of Sports Medicine compared the effectiveness of interval training to moderate-intensity continuous exercise. Researchers discovered that both forms of training helped lower body fat percentages, regardless of an individual's sex or starting weight. However, interval training provided a 28.5 per cent greater reduction in body weight than moderate intensity continuous exercise — pretty impressive, considering the shorter work time.
But how short can you really go? Apparently, as little as one minute. Martin Gibala, chair of the kinesiology department at McMaster University, studied the effects of one minute of high-intensity exercise, broken up into three 20-second intervals. Along with rest periods, warm-ups and cool-downs, the workout in his study totalled just 10 minutes. Gibala found that three of these workouts per week yielded similar health benefits as 50 minutes of moderate continuous exercise, also carried out three times a week. And interval training may not boost just your body: another study found that such exercise can also improve your memory, too.
But before you hop up and start exercising, take note: just because interval training is effective in theory, doesn't necessarily mean it will be effective for you. Experts agree that you have to be the right candidate for the method and know how to use it correctly to see positive results.
Here's what a few Canadian fitness pros think you should know about interval training.
The potential benefits
The biggest plus of interval training may be its efficiency. "It's a great workout when you're limited for time," says Canadian fitness professional Danyah Rivietz. "It burns a lot of calories in a short session, compared to steady-state cardio." Interval workouts also "produce an 'afterburn' effect that allows your body to stay in fat-burning mode long after your workout is finished," explains Jennifer Lau, Nike master trainer and co-owner of Toronto training company Fit Squad.
Lau goes on to say that interval training has a protective effect on muscle mass, making it an ideal option if you'd also like to maintain or increase muscle. But it can also make for an effective whole-body workout. "Interval training can be a combination of cardiovascular exercises, plyometrics and weight training exercises," says Rivietz, which also makes it "a great way to keep workouts fun, interesting and challenging."
What's more, because interval training is more of a method than a workout, it's extremely adaptable. "Each exercise can be scaled so that all fitness levels are accommodated," says Rivietz. "It doesn't require much equipment, making it great for traveling and home workouts, if you can't get to the gym."
The common pitfalls
Just because interval training tends to be efficient and effective doesn't mean more is always better. With higher intensity you also need greater rest and recuperation so your body can fully reap the rewards. "Often people do too much, too soon, rather than working their way up slowly," says Rivietz.
This can easily lead to overtraining, "making it more difficult to recover between workouts," adds Sergio Pedemonte, personal trainer and CEO of Toronto-based training company Your House Fitness. "Don't engage in interval training on back-to-back days," advises Rivietz. "You may also need more than one day to recover after your first session."
With a higher intensity also comes a higher risk of injury. "There can be a degradation of technique due to the fast pace of movement as well as the high levels of fatigue produced," says Lau. It's important to first master the form of each exercise, ensuring you're comfortable and pain-free, before adding in the interval intensity. Rivietz says that it's also crucial to have a fitness base, in the form of some cardio and weight training experience, before jumping all the way in.
And since interval training can be taxing enough on a healthy body, you should take extra precautions, and possibly abstain from the method, if you already have physical issues. "If you have a pre-existing injury or a heart condition, you should consult a doctor before starting interval training," Pedemonte says.
All aboard the interval train
So you're healthy, have developed good form and are ready to up your training, interval-style. First, remember that it's important to do an active warm-up to prepare your body for what it's about to go through. Pedemonte suggests dynamic stretching for five to 15 minutes to slowly increase your heart rate, warm up your muscles and get your joints ready for the exercises you're about to perform.
If you're putting together your own interval workout, Rivietz suggests you start slowly, "picking two or three exercises you are proficient at" and "making your rest intervals long enough to recover." Since intervals are adaptable, you can start with exercise times shorter than your rest times (30 seconds of jumping jacks, 1 minute of rest). Once you've built up confidence, you can increase the exercise times (45 seconds of jumping jacks, 1 minute of rest) and lower the rest times (1 minute of jumping jacks, 30 seconds of rest).
Always make sure your body dictates the intervals, not the other way around. The experts agree that pushing yourself past exhaustion ultimately isn't beneficial, so always adjust your exercise and rest periods to how you feel and perform.
When picking exercises to include in your workout, Lau suggests starting with bodyweight movements such as mountain climbers, air squats and lunges. "Don't be in a rush to incorporate free weights until you feel ready to do so," she says. Lau also recommends downloading an interval timer app on your phone, so you can more easily track, adjust and record your workouts.
Need a head start? Pedemonte has created some sample interval training routines, one beginner and one advanced, to point you in the right direction. (As with anything workout-related, if you're unsure or uncomfortable, consult a personal trainer to make sure you're on the right track.)
Beginner interval training workout
Two to three rounds containing 10 reps of each of the following exercises, with a 30- to 60-second break between each round:
- Air squats
- Downward dog
- 30-second plank
Advanced interval training workout
Three to five rounds containing as many reps as possible of the following exercises within 30 seconds, with 15 to 30 seconds of rest time between each round:
- Jump squats
- Mountain climbers
- Pushup to downward dog