Login | June 03, 2020

HIIT workouts

Pete’s World

Published: November 4, 2019

HIIT workouts. Maybe you’re familiar with them, maybe you’ve even participated in them then again, maybe you see them offered at your fitness facility, but you’re not quite sure what they’re all about and whether you should do them. And it’s to this latter group that I’d like to address today’s column.
So let’s take a look at HIIT’s popularity, the science behind it, and for whom it’s appropriate.
HIIT is the acronym for High Intensity Interval Training, and it refers to a type of training that involves repeated bouts of high intensity efforts followed by varying periods of recovery.
First, let’s look at why this workout format is so popular.
Well, exercise science has shown HIIT training to be a good way to improve numerous fitness components, components like aerobic and anaerobic fitness, blood pressure, cardiovascular health, exercising muscles’ ability to more easily use glucose for fuel, cholesterol profiles and body composition (more lean muscle tissue/less adipose tissue).
But the biggest benefit that HIIT enthusiasts rave about is the fact that this variety of training can burn more calories than oft used cardiovascular exercises like running, swimming and biking when comparing equal volumes of time spent working out.
For example, the Journal of Strength and Conditioning Research, 2015 Mar;29(3):779-85, details a study which found data that suggests “individuals can burn more calories performing a HIIT session with an HRS [hydraulic resistance system] than spending the same amount of time performing a steady-state exercise session.
This form of exercise intervention may be beneficial to individuals who want to gain the benefits of both resistance and cardiovascular training but have limited time to dedicate to exercise.
And that’s another thing that HIIT proponents like about this brand of training, the fact that you can get more bang for the buck with respect to time spent workout out.
And I’ll tell you what, that JSCR study is just one of many such studies in peer-reviewed journals that are yielding some very good data to support all the hype surrounding HIIT workouts.
So what’s the science behind this workout format that makes it so successful?
First, HIIT workouts can prod the body into making a metabolic shift in energy consumption from carbs to fats.
And second, one of the most well-documented physical reactions to a HIIT session actually occurs after the workout, and that’s an increase in one’s metabolic rate.
This phenomenon is referred to as post-exercise oxygen consumption (EPOC), which is the body burning more calories for 24 to 48 hours post-workout.
Furthermore, this EPOC occurrence is beneficial in several other ways.
For instance, it improves aerobic stamina and it can increase oxygen consumption such that fat can be burned up to nine times faster than normal.
This “afterburn” benefit is really huge, because it’s a 24/7 calorie burn, more effective for weight loss than say, an hour or two of steady state running, cycling, etc.
Now, with respect to who should and shouldn’t participate in HIIT workouts, the following individuals absolutely should obtain medical clearance from a physician before starting any form of HIIT training: Those who have been sedentary for a long period of time, those who have coronary artery disease or a family history of coronary artery disease, cigarette smokers and those who have hypertension, diabetes (or pre-diabetes) and/or abnormal cholesterol levels.
If you’re free and clear of the aforementioned medical contraindications, you should also possess a base level of fitness. And that’s defined by participation in some form of aerobic exercise that’s performed three to five times a week for at least 20-plus minutes per session, and those sessions should include periods where the exercise intensity could be defined as somewhat hard to hard.
What’s more, potential HIIT participants should possess a basic knowledge of proper exercise form and a marginal level of muscle strength, both of which are necessary to reduce the risk of musculoskeletal injuries.
As you can see, HIIT workouts are not recommended for exercise novices.
Okay, so that’s the short skinny on HIIT training.
And for those of you who have been on the fence with respect to participating in HIIT workouts, I hope this gives you a bit more clarity with which to base your decision.