Is Your HIIT Rest Time Too Long?

February 22, 2023 Ashley 0 Comments

Think we’ve beaten the HIIT horse to death into glue?

Well, saddle up, Elmer, because there’s still more to say…

So, last HIIT article, we looked at some evidence based research.

In one specific study (a comprehensive review, no less), the conclusion tried to state that HIIT didn’t accomplish as much as we thought it did for weight loss. It was even beat out by steady state cardio. Naturally, a player of Devil’s advocate (and advocate for all things HIIT), I listed a million variables the study doesn’t address. HIIT can be done more ways than just on a bicycle (which the study used exclusively). HIIT weight loss results can be affected by diet. We won’t reiterate everything, but there are so many things to consider that make a statement like “HIIT doesn’t result in significantly more weight loss than any other type of cardio” such an erroneous one.

However, I’m actually more disappointed in myself on this one; because for that whole long paragraph of “what if’s” I painstakingly scrawled out, I missed the biggest one. I missed what the study had done wrong. (Aside from failing to compare different forms of cardio.) What the study did do was compare HIIT to sprinting and steady state cardio. The result was to write off HIIT as the winner for weight loss workouts and caloric burn. What the study didn’t do was consider the actual HIIT parameters. It didn’t ask two very important questions. The first is, “Are these intensity sprints long enough?” and the second is, “Is the interval between each of them short enough?” I only even thought to ask this question as I completed a workout the other morning that featured one or two longer-than-usual sprints with every sprint bordered by less recovery time. The overall all-out time was roughly the same. But with that reduced recovery time, I was gasping and sweating far more than I usually am by that point in my cardio workout.

So, naturally, I looked it up.

And, sure enough, there’s a science to it.

First thing’s first: any form of HIIT is going to be great for you. Injecting whatever number of intensity sprints into your workout will be helpful for health. It doesn’t matter if you go HAM for 30 seconds and rest for a few minutes before resuming, or if you narrow that rest time down. Either way, you’re challenging yourself in a way that’ll benefit your fitness overall. So, let’s clarify that before anything else. That being said, as you continue to improve your fitness and can tolerate more, the experts suggest it’s best to do exactly that – and decrease that down time between going full speed. Too vague? Not a problem – because according to a Liverpool study done several years back, there’s a sweet spot for weight loss with HIIT. The research compared a version of 30 HIIT and 60 HIIT (two popular forms of high intensity interval training). In the former of the two, you do 30 second intensity intervals (about 4 to 8 times) with a two minute rest in between each of them. In the latter, you go for 60 second intervals (6 to 10 times) with only a minute in between intensity bouts.

Obviously, it shouldn’t be too unclear why 60 HIIT beats 30 HIIT toe to toe (since one has fewer intensity intervals, shorter intervals, and a longer rest); but the study made sure to accommodate for that. And the results were clear. After making everything equal except the time in between (60 versus 120), the minute interval was the winner. Whether you do 30 second bouts or 60 second bouts, two minutes is one minute too long for optimal results. Now, I say this with a grain of salt. To reiterate what was said above: doing something is better than nothing. When I first started running intervals, I began at a pace I’m ashamed to say, for an amount of time I’m ashamed to say, with a rest interval between each that I’m turning red with embarrassment to even recall personally in the privacy of my own brain. It wasn’t even on par with the “lesser” 30 HIIT that’s being offered the bronze in the latest HIIT studies. The good news? Starting out with that laid the foundation for me to improve. I set small goals for myself, improved a little every couple of months, and now I’m at peak cardio. For a while, however, I had to give myself some grace with my pace and interval stats until I hit that plateau.

Otherwise, I’d have gotten too frustrated and given up.

In the end, that’s what it’s all about.

Remember that there’s what’s “best” and there’s you doing your best – for where you’re at. We’ve all got to start somewhere. If your somewhere is similar to my early-years laughable workouts, don’t get down on yourself. Your first step is even taking those steps at all. *Just begin. That’s all. Then, as you improve and it gets easier, don’t rest on your haunches. Just like we need to know when to back off – we also need to know when it’s time to level up. Ask yourself if your sprints should be longer or if your rest time could be reduced. Then, be very honest with yourself as you answer that. Get uncomfortable being uncomfortable and go after that growth. Not sure if you’re doing enough? Well, I’m not saying that being gross and sweaty and gasping for oxygen by the end of your workout is a requirement for effectiveness – but it’s a pretty solid indicator that you gave it your all today.

*As ever, check in with your physician before starting a new exercise program.