The Disadvantages and Unspoken Benefits of HIIT

The Disadvantages and Unspoken Benefits of HIIT

James FitzGerald on HIIT

High-Intensity Interval Training or HIIT is probably the second biggest buzzword in the fitness industry behind Keto. HIIT is a style of exercising that focuses on high levels of effort for a short amount of time followed by a period of rest, repeated for a certain number of intervals. 

While this concept has been around for years its popularity has skyrocketed recently due to its claims to get clients fitter, leaner, and stronger faster than any other methodology. But there are some disadvantages to HIIT and some unspoken benefits that OPEX Fitness Founder, James FitzGerald believes it’s time to talk about.

James FitzGerald’s Experience with HIIT 

James FitzGerald, the inaugural winner of the CrossFit Games, is no stranger to HIIT, as he pointed out during his keynote at the 2019 NASM OPTIMA Conference. “I didn’t just drink the kool-aid, but bathed in it.” But with more than 25 years of coaching experience under his belt, the founder of OPEX Fitness now sings a different tune.

Put simply James’ believes that there is no reason fitness coaches and clients should use HIIT if their goal is general health and wellness. 

So why does James advise avoiding HIIT when the market is touting its benefits and its popularity is only rising? He does so because of the amount of stress HIIT puts on the body and what that stress does over time.

Why HIIT Works

Exercise drives results because the body is responding and adapting to stress. Since HIIT is highly stressful on the body, coaches and clients see adaptations (results) very quickly. However, this type of highly stressful work can only be maintained for so long.

The Disadvantages of HIIT

The truth is that when you look closely at most studies praising HIIT and the gyms that are using it, it is only for a short period of time. Clients come in, get started, and see results, which is great for the study and the business. 

Eventually though, the clients stop seeing results stop, start losing mental acuity, and begin developing compensatory patterns. Before anyone knows what happened the client has plateaued and can’t seem to squeak any extra pounds out of their squat.

(Coach’s Resource: Clients plateaued? Learn the basics of creating individualized and progressive exercise plans here.)

Why does this happen? The body can only handle so much stress. At first, clients will adapt and adapt quickly feeling as though they are watching their body change before their eyes. But this rapid stress adaptation is peaking the client’s physical abilities too early and after a short period of time clients will stop adapting and results will halt.

Who Should Do HIIT and Its Benefits

As he stated at the beginning of his speech James believes that HIIT has no place in general health and fitness training and rightly so. But this does not mean that HIIT has no utility. There are three benefits of HIIT training and certain clients can benefit from it.

Firstly, HIIT creates a stress response. This is valuable for clients that need to work in scenarios of high stress such as high-level CrossFit athletes. Learn more about how to work with athletes here.

Secondly, when done correctly HIIT can create a metabolic response and increase a client’s ability to use lactate. Again this is only needed for specific purposes such as CrossFit and combat sports. 

Thirdly, HIIT can boost the aerobic system. HIIT will not increase aerobic capacity, but it can help clients flirt with threshold without causing a decline in power output. For example, in the case of a marathon runner who has to run up a series of small hills throughout their race.

What Clients Actually Need: The Alternative to HIIT

When it comes to exercising for general health and fitness James emphasizes to keep it simple. “Most clients just need weight training and slow aerobic work, both opposite ends of the spectrum when compared to HIIT”. 

The goal of the exercise is always to support the act of living the best possible life. Weight training and slow aerobic work support clients more effectively than HIIT because the two create a broader base of fitness and progress them in a more sustainable way allowing them to reach a higher peak of physical potential. 

This slow approach works in two ways: 

1. Weight training builds muscle endurance, giving clients the support they need to work up the muscle endurance tree. Learn more about progressing the muscle endurance tree here.

2. The slow sustainable aerobic work teaches clients repeatability, giving them the ability to make faster paces more aerobic over time. Learn how to progress aerobic training here.

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