UBC Okanagan researchers look at when interval exercise can be beneficial

Photo: UBC Okanagan

A team of UBC Okanagan (UBCO) researchers are diving into the science of when high-intensity interval training (HIIT) is the best way to exercise.

It's been a controversial topic for years, says study lead author Matthew Stork, who is a postdoctoral fellow in the School of Health and Exercise Sciences.

“The physiological benefits of HIIT or SIT [sprint interval training] are well established. What has been difficult to nail down is if interval-based exercise should be promoted in public health strategies. If so, how can we help people, especially those who are less physically active, get that kind of exercise on a regular basis and over the long term?”

He says HIIT can fit appropriately into a 'menu' of flexible exercise options, and defines it as repeated short, high-intensity efforts separated by periods of low-intensity rest or recovery, lasting about 20-25 minutes or less.

“I think many people assume that they need to go all-in on one form of exercise—if they’re a ‘HIIT person,’ they must have to do HIIT all the time,” he says. “But what I’m seeing is that different forms of exercise can be used interchangeably and that people should approach their exercise with a flexible ‘menu’ of options.”

He also points out the difference between HIIT and sprint interval training (SIT). HIIT usually consists of bouts performed at about 80 to 90 per cent of a person's maximum heart rate, whereas SIT involves shorter bouts of activity, but at an even higher intensity. 

“While SIT can be attractive for those who feel particularly short on time, it can be pretty off-putting for those that aren’t used to exercising at all-out intensities,” he says.

“Unsurprisingly, different people tolerate different exercise programs in different ways. That makes it difficult to establish the ‘best’ exercise program for the ‘average’ person. There’s little research to unpack the experiences and perceptions of HIIT and SIT compared to traditional continuous exercise in the way we have in this study.”

Thirty inactive adults were interviewed before and after participating in various types of continuous and interval exercise in a controlled lab setting, and in their own free time, as part of the study.

Stork says the next stage of the research will be to determine what tools and resources can help people engage in either activity on their own.

“If we can provide more guidance on how people can adapt interval exercise to cater to their own fitness levels and needs, the more likely they may actually enjoy it and stay motivated. I’m a big believer in the benefits of regular physical activity, and the more barriers we can remove, the better.”

The research was published in the Psychology of Sport and Exercise journal, supporting with funding from the North American Society for the Psychology of Sport and Physical Activity.