Understanding HIIT. When it comes to exercise, can less actually be more?

by Aaron Hewitt PA-C, Physician Assistant
OrthoCarolina’s Sports Medicine Center

You’ve likely heard of high-intensity interval training (HIIT), a type of workout that isn’t totally new, but is increasingly popular and can be confusing because there are so many types.

Usually short in duration, the HIIT intervals incorporate intense periods of work followed by low-intensity segments or rest, increasing both your aerobic and anaerobic capacity. Whether it’s CrossFit, P90X, Insanity, Tabata training, Jillian Michael’s 30 Day Shred or any other variation, these workouts can seem intimidating or downright scary if you’ve never tried one. Can I physically do the exercises and keep up with everyone? Will I get hurt?

CrossFit has been a big part of my life for 4 years now. I’m lucky because I’m able to be a participant and even compete in CrossFit competitions from time to time.  Because of my job as a P.A. at OrthoCarolina in Charlotte, I have the perspective of a medical provider to understand how the body functions, adapts and ultimately gets stronger when put through that type of work.

In answer to the less can be more question, HIIT has been shown to burn adipose tissue, or body fat, more effectively than low-intensity exercise, plus rev your metabolism. When people develop muscle mass they actually burn more fat, because muscle requires more energy. In these types of classes you’ll see toning and definition and you’ll work a variety of weights from kettlebells to dumbbells to weight bars, punching bags and more. High-intensity training like CrossFit works on strength training, something females often neglect, while still offering effective cardio workouts.

So if you want to try one of these intense workout classes, how do you know which is best for you? When researching your options, I recommend keeping the following tips in mind:

Look for quality coaches and trainers. Many fitness locations offer the first class free, so check out a few and pay attention to the instructors. A coach should be willing to work with you individually and help you with better form, or even an individualized plan.

Ask about scalability. Any quality CrossFit or interval training program offers a scalability option. Athletes have varying strength abilities, so classes should offer modifications.

Start slow. You will probably be sore after your first session, so go easier in the beginning and progress slowly as you adapt to the routines. High-intensity doesn’t need to mean high-impact. If box jumps or burpees aren’t for you, a quality gym will have an alternative.

Listen to your body. Anything done in excess has an inherent risk of injury, so stop if something hurts or bothers you. If you do have aches and pains, stick to the RICE treatment (rest, ice, compression, elevation), and seek medical treatment such as a sports medicine provider if it hasn’t improved in two days.

MYTH BUSTING:  Don’t apply heat to a muscle pull or post work out strain.  The reason?  Because doing so will significantly increase blood flow to the area, which in turn will increase swelling and adversely affect the immediate healing process. While heat helps to loosen muscles that are sore or cramped, common thinking today is that it should not be used for acute injuries like muscle strains.

As you get more used to high-intensity, your functional movement should improve, meaning your body will be physically better-equipped to perform during sudden movements in everyday life situations. If you choose to stick with the training, use it as an adjunct to your primary workout in conjunction with longer aerobic workouts such as jogging, flexibility or cycling. Challenging the muscles with different physical activities helps improve your proprioception, balance and agility, leading to a stronger athletic baseline. It’s important to mix it up!

Aaron Hewitt PA-C, is a Physician Assistant with OrthoCarolina’s Sports Medicine Center.

He is a former Assistant Athletic Trainer with the Minnesota Vikings (NFL), and is an orthopedic provider for UNC-Charlotte and Myers Park High School. He also is a Physician Assistant Team Lead for Sports Medicine, Spine, Hand & Pediatrics and a Clinical and Surgical Preceptor for Physician Students.

In addition to CrossFit, Aaron is dedicated to running, yoga and clean eating.


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