Celebrities Britney Spears, Scarlett Johansson, and Jennifer Lopez are all fans of one type of training that is taking the health and wellness world by storm – HIIT. Even trainers like Jillian Michaels and celebrity trainer Jorge Cruise have both previously told INSIDER they are fans of the fat burning workout.
Eric Salvador, head trainer at Fhitting Room – a 50 minute HIIT class in New York City – told INSIDER that HIIT stands for high-intensity interval training, and is essentially the opposite of a long and steady workout.
“HIIT incorporates short bursts of workouts which will make you feel very uncomfortable implemented with some active recovery or rest for different kind of variations of time, so the ratio of work to rest is something that we play with,” he said.
According to Salvador, HIIT is beneficial because it works the full body and tests both strength and endurance using compound movements.
With those benefits in mind, Salvador noted that some people could sabotage their HIIT workouts by making common mistakes. Here’s what you might be doing wrong with HIIT and how to make the most out of your training.
You’re making the workout too long.
One of the perks of HIIT workouts is that they are short. Adding more time won’t make them more efficient.
Salvador said HIIT work varies from four to six minutes of “going all out” and then resting. Longer HIIT workouts, however, are one of the first mistakes he often sees with people trying out HIIT for the first time.
“Long workouts […] they are not HIIT,” he said. “You can’t do a HIIT workout for a very long time. Some of the HIIT workouts I have done lasted 10 minutes, with rest involved, so the actual amount of work I am doing is different.”
Salvador added that some workouts are promoted as HIIT when they aren’t. The way to determine if you are actually doing HIIT is if there are changes or intervals of intensity.
You skip your warm up.
You should never skip your warm up no matter the exercise, but it is especially important to warm up for a HIIT session. According to Salvador, the shorter the workout, the longer you have to warm up since you are taking your body from one extreme to another.
“If I have a really long workout I don’t have to warm up as much because then in that long workout I start to warm up within the first five minutes,” he said.
“So warm-ups are very important, and what I mean by that is getting the body moving, getting a little sweat involved, before you hit something that is really intense to prevent that heart [rate] spike right off the bat.”
You’re just resting during your average workout, and not upping the intensity.
For HIIT to be effective, you have to implement both the high-intensity work and intervals. So if you are simply adding breaks or rests into your typical workout without upping the intensity, you aren’t doing HIIT, according to Salvador.
“Once you start losing the intensity basically you are just working out and resting for 30 seconds which is not very intense, and now your workout starts to diminish,” Salvador said.
One example he gave was if someone did a HIIT workout and rested as necessary but didn’t really sweat or feel challenged, that points to a mistake in intensity. Some people, according to Salvador, don’t know how to measure intensity.
On a scale of one to 10, one would be sleeping, and a 10 would be feeling like you couldn’t possibly do any more work. For HIIT, you should be in the eight to 10 range, according to Salvador. If you stay in the lower levels, you aren’t really challenging your body or getting the most out of your workout.
To make an exercise more intense, Salvador recommended changes like turning a normal step up on a box to a box jump or turning a dumbbell curl into a dumbbell curl and squat. Changing up these moves will make your body work more, tax more muscles, and burn more calories.
You aren’t taking rests.
On the other end of the spectrum are people who pedal to the metal at the beginning of the workout and don’t take the necessary breaks. Doing this, in turn, messes with their intensity for the rest of the workout.
“The mistake is that people go hard, but they don’t recover, and then their effort [later on] isn’t where it was when they were fresh,” Salvador said.
“The more intense the workout the more rest you need so if I am telling you that you are going for a 400 meter sprint around the track, and it took you a minute, and 45 seconds I’m going to need you to recover for the same amount of time it took you to run it,” he added.
Essentially, Salvador said you should be resting for about equal to whatever work you did or less. As you get fitter you will need less time for recovery, just remember to maintain the same level of intensity and effort during every burst of movement to avoid burnout.
You try to implement isolation work.
There is a time and a place for isolation work, but according to Salvador that isn’t during HIIT. The isolation work he talked about includes machines at your local gym that targets one part of the body, like a leg extension or even a free weight movement like a bicep curl.
Movements like these that are often supported by machines and are comfortable and controlled don’t prepare the body for everyday stressors such as walking up the stairs to your apartment or lifting boxes.
“We want you to feel uncomfortable, we want you to stand there supporting your own body weight, and we want you to use full body movements […], so the full body movements are key,” he said.
“They transfer over to everyday life activities whether you are pulling or pushing jumping, climbing up stairs or carrying stuff back from the supermarket. So the functionality of [HIIT] has carryover to everyday life is huge.”
You do HIIT too often.
HIIT can be a great addition or substitute for your average workout, but there is such a thing as too much of a good thing. And doing HIIT too often is one of them.
According to Salvador, the benefits of HIIT diminish when you overdo it since that could lead to injury or exhaustion. Although the workout is popular for being effective and a time saver, many new people jumping onto the trend make the mistake of doing HIIT too often – and not giving their body time to rest, according to Salvador.
“You can’t say I have to do HIIT seven times a week. Absolutely not you need to recover,” he said. “
“People are hitting it too hard and too much […] then you start to find people are getting injured now and it is because of the frequency of the exercises they are doing.”
To avoid injury, Salvador recommended monitoring every part of your recovery between workouts including your sleep and diet. He suggested doing HIIT three to four times a week tops if you are following all his other guidelines like actually taking rests and upping the intensity.
Like any new workout, Salvador recommends taking things slow and giving yourself time to acclimate to the real intensity of HIIT training.
“Because I think if you are enjoying HIIT training, you’re not doing it right.”
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