The dos and don’ts of HIIT

Most gyms have jumped on the HIIT (high intensity interval training) bandwagon offering workouts fashioned after the immensely popular CrossFit.

Exercisers perform multiple short, high-intensity intervals interspersed with short periods of recovery.

The work interval spans 20 to 60 seconds, during which multiple repetitions of the same exercise are completed — followed by 10 to 15 seconds of rest. Sometimes, the work intervals alternate between three and four exercises; other times, the same exercise is repeated for a predetermined number of rounds.

An example of an HIIT workout would be 45 seconds of squats/15 seconds rest, 45 seconds of burpees/15 seconds rest, 45 seconds of kettlebell swings/15 seconds rest and 45 seconds of pushups/15 seconds rest. The object is to perform as many repetitions as possible in 45 seconds, rest and repeat.

One complete cycle through all four exercises equals one round. A full workout usually consists of several rounds, often with a longer rest between rounds. The goal is to exercise at the higher end of the intensity spectrum in those short bursts versus maintaining a more moderate intensity over a longer period of time.

HIIT workouts have become popular because they boast the same or better fitness benefits as workouts that take twice as long, making it possible to do in 10 or 15 minutes what it used to take 30-plus minutes.

And the science is sound; more and more studies are suggesting not only are short, intense workouts amazingly effective, they’re also suitable for all types of exercisers, including novices and people with cardiovascular disease.

Yet despite the proliferation of HIIT-styled classes across the country and favourable reviews from exercise experts, not all is right in the world of HIIT classes.

The problem lies not in the exercise format but in the way some classes are structured. Combine poor class design with the natural competitiveness when pitting yourself against the clock and it’s easy to see why some experience more than a fair share of aches and pains.

In an effort to keep a good workout from going bad, here are a few fitness fundamentals that will make HIIT workouts safer and easier on the body without losing any of the challenge that makes them so effective.

1. Do the warm-up

A comprehensive warmup is crucial to both prime your body for the work ahead and ensure you’re up to performing at the intensity HIIT workouts demand.

A good warm-up takes at least 10 minutes and starts with an aerobic component (jogging) that boosts blood flow and increases joint viscosity, followed by a series of full-body, large range-of-motion exercises that mimic those you will perform later.

Keep your warm-up at a moderate pace until you transition into the more intense portion of the workout and do not cut it short.

2. Train more than one or two muscle groups

Some HIIT workouts focus on training one or maybe two muscles groups, claiming that complete muscle exhaustion is the way to break through to the next level of strength or fitness.

This type of repetitive stress to a single muscle group can cause acute damage; not only can it keep you out of the gym for weeks, it can send you to the emergency room in extreme pain.

The best workouts challenge all major muscle groups by balancing upper, lower and core body exercises to achieve improvements in strength, endurance, coordination and fitness.

3. Put form first

The popularity of bodyweight exercises in HIIT classes doesn’t mean they’re without risk. In fact, any exercise done with poor form, whether or not you use equipment, can injure. Add the elements of fatigue, speed and repetition, and the risk of injury jumps.

Once you feel your form slipping, either modify the exercise to an easier version or take an unscheduled rest until you’re ready to complete another couple of reps with impeccable form.

4. Listen to your body

Sure, the idea of HIIT is to push yourself, but don’t ignore the your body’s signals when it’s pushed too hard. Discomfort due to effort is fine; pain tells you to either slow down, modify the exercise or stop.

Common sense, yes; but sometimes good judgment is abandoned trying to squeeze in a few more expected reps before the interval’s end.

You should feel energized, not exhausted, after a workout and nothing should hurt — ever. Don’t worry about generalized muscle soreness 24 to 48 hours after a tough workout, if it’s equal on both sides of the body.

Remember, the goal of exercise is to feel better, not worse, so knowing when to turn it on or dial it back is key to long-term success.