Featured story October 27, 2015
“It’s a massive fashion trend at the moment,” says personal trainer Sandra Scannell, owner of Fit Republic in Fermoy, Co Cork.
She is talking about high-intensity interval training, or HIIT, a type of exercise that alternates between intense bursts of activity and periods of rest.
In a HIIT class, Scannell says, one muscle group is worked to exhaustion by repeating the same pattern several times. An example is running as fast as possible for one minute, then walking for two minutes and repeating that five times.
In Scannell’s classes, she does intervals of exercises that target specific muscle groups.
“We might get five or six muscle groups done within half an hour. The point is to exhaust the muscle group.”
HIIT is a way to “get fit quick”, she says, and that is part of its appeal, especially for the time-starved.
“The workout is that short because you’re taking your muscles to their maximum capacity. At the end of 30 minutes, if the exercises are performed correctly, you realistically shouldn’t be able to do any more.”
According to Scannell, HIIT training improves the metabolic rate and trains the cardiovascular system. Other benefits? You can do it anywhere and do not need equipment.
Appealing as that is, she does not recommend HIIT training to just anyone.
“If you ring me from the couch, you’re not getting into the class. You’ll probably end up throwing up, and that won’t do anything for your confidence.”
For safety reasons, Scannell makes sure her HIIT clients are already fit and active. Her classes are popular with athletes.
Even the physically fit “will generally go through a bit of pain”. She says delayed onset muscle soreness is common “because you’re pounding away at the same muscle group over and over. General classes won’t take the muscles to that extreme.”
John Sharkey, president of the National Training Centre, also would not recommend popping into your local HIIT class with no assessment.
The exercise physiologist and clinical anatomist says people should build up their fitness levels before trying HIIT.
Sharkey says high intensity workouts have always been popular, and people have always loved intense workouts that make sweat pour down their foreheads.
“It’s just that it’s more structured now and more formatted. I can’t keep up with them. Somebody comes out with a 25 minute workout, then somebody else comes out with a 24 minute workout.”
While the research is “a bit difficult to siphon”, it “shows tremendous benefits [of doing HIIT], provided it is prescribed by a reliable source: a qualified personal trainer or fitness instructor.”
But, Sharkey says, the biggest problem with people exercising intensely is not warming up properly, which “could have a negative effect on your heart . . . If you haven’t done a warm-up to give your body those minutes to adapt, then you are putting yourself at risk.”
He says people should take at least 10 minutes to warm up, in order to get their hearts ready for exercise. Then, as importantly, people should give their bodies time to recover.