The studies, research and personal testimonies are all out there. So, it looks like high intensity interval workouts here to stay and apparently a healthy way to exercise.
Of course, that doesn’t mean low intensity or endurance programs should be, or have to be, ditched entirely.
“I am certainly an advocate of high intensity workouts. It has a place in anyone’s program,” said Jessica Matthews, exercise physiologist at the American Council on Exercise in San Diego. “The pendulum is swinging now – many people have abandoned longer workouts and have focused solely on high intensity. But, low and moderate intensity (workouts) have benefits, too.”
A recent study in Norway took two groups of healthy, inactive men who were slightly overweight. Three times a week one group did endurance workouts for 40 minutes and the second did more intense workouts for 19 minutes.
Both groups saw significant health improvements - like higher oxygen capacity, and the normal benefits of exercise like decreasing the risk of heart disease, hypertension and diabetes. But the high intensity program also saw more reductions in body fat, blood pressure and various cholesterol levels.
“We have a worldwide obesity epidemic and even though people are told they should exercise around 30 minutes a day at least five times a week, only about 15% to 30% of people do this. Our study suggests that around 15 minutes of exercise, three times a week may have significant benefits as long as just a few minutes include intensive endurance training,” said Arnt Erik Tjonna, from the K.G. Jebsen Center for Exercise in Medicine at Department of Circulation and Medical Imaging in Trondheim, Norway.
High Intensity Interval Training (HIIT) vs. aerobic or low to moderate training is akin to a sprinter vs. a marathon. Sprinters go all out, 100% of the time for short periods of time, while marathoners don’t use all of their energy at the start in order to last a long time.
A HIIT training session usually consists of a warm-up, a certain amount of quick, intense repetitions of an exercise, and then a short cool-down or low intensity period. The intense and cool-down periods are repeated and can last up to 30 minutes.
Another study, in England, had 16 young males do either 40-60 minutes of cycling five times a week or 4-6, 30-second bike sprints with 4 ½ minutes of low intensity biking in between each. This was done three times a week.
The results showed that both workouts – five hours of endurance training and 90 minutes of a HIIT workout – resulted in the same improvements in many areas of health.
There are many styles and different forms of HIIT training – CrossFit, Tabata, P90X, Insanity and many others.
Keith Hollifield, Fitness director at Desota Athletic Clubs, which has locations in Mississippi and Tennessee, swears by the short, intense workouts. Not only is employed in his clubs, through Rick Mayo’s North Point Fitness platform, but it has helped get the 56-year-old in the best shape of his life.
“You hear the stories of those who do circuit training and they don’t break a sweat. If you do (high intensity workouts) you see immediate results,” Hollifield said. “I used to work out the old way but now I am in the best shape of my life.
“We are working out intensely – the heart rate is up, the lactic acid thing is happening. And with high intensity workouts we get the after-burn, when calories are burnt hours after a workout. On many machines you burn your last calorie once you finish your workout.”
Hollfield explained that North Point Fitness uses the standard high intensity workout accessories like TRX bands, kettleballs, sandbags, ropes, etc.
He added that the HIIT workouts at Desoto draw quite a bit of attention as not only is it intense but it takes place in the middle of the gym with the circuit stations and aerobic machines, like treadmills and exercise bicycles, placed around the perimeter. Those who work out “the old way,” as Hollifield puts it, see the fun HIIT attendees are having and the smiles on their faces and often will try it out at least once.
And with the popularity and success of HIIT workouts has come the endurance race phenomena. Or, maybe it is the other way around? Events like Tough Mudder, Spartan Run, Warrior Dash and other races have sprouted up everywhere in the last few years and possibly in order to get ready for them this type of workout was necessary.
“(HIIT) translates to what many people are now training for, the endurance events,” said Matthews of ACE. “Plus it is great for overall conditioning – less body fat, lower blood pressure, the things we all know exercise does - but does in less time.”
And a final benefit of HIIT workouts is that, according to some studies, people are enjoying it more and are more likely to stick with the training and not give up and sit on the couch.
“Many people want something to push their fitness to the next level, to step out of their comfort style,” Matthews added. “There was a study out of France, that said groups who did high intensity training were more inclined to stick with it longterm.”