The Power Of Faster Reps

The latest science says that this simple shift – speeding the pace of your sets – accelerates your strength gains. Here’s exactly how to tap the effect.

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The latest science says that this simple shift – speeding the pace of your sets – accelerates your strength gains. Here’s exactly how to tap the effect.

Turn the page for moves, techniques, nutrition, and tools for your best strength HIIT results.


Much has been made of the advantages of doing high-intensity intervals versus steady cardio, but new research has found a similar boost applies to strength training. In a study from the American Council on Exercise, exercisers who did five-rep sets quickly with shorter rest in between (called HIIT style) got the same or better results in muscle fitness compared with those who did traditional moderate-intensity strength sets – even though the latter group was doing more reps for twice as long (45 minutes versus 20).

“The HIIT workout was better at providing that necessary stimulus to the muscles to have a more favourable training adaptation,” says lead researcher Lance Dalleck. In other words, HIIT netted a slightly better strength boost in half the weekly time commitment. The fact that the HIIT exercisers also used the max weight they could muster for exactly five reps was key in pushing their muscles to their limit – the sweet spot you want to be at, Lance says. 

Put this science into practice with the mini circuit on the next page by Autumn Calabrese, creator of the 80-Day Obsession online programs. Grab a set of weights that feel challenging for the number of reps listed, and do two sets each at a fast clip.

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Stand with feet wide and toes turned out, holding 1 weight at ends with both hands in front of chest to start. [A] Squat, rotating torso to right and reaching weight above right foot (arms go on both sides of knee). [B] Stand, curling weight to chest, then press it overhead as you rise onto balls of feet. Return to start position. Switch sides; repeat. That’s 1 rep. Do 10 reps.

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Stand with feet hip-width apart, holding 1 weight at ends with both hands at chest level to start. Lift left foot off floor. [A] Squat as low as you can. Stand, lift left knee to hip level. [B] Press weight overhead as you straighten and extend left leg to side. Return to start position. That’s 1 rep. Do 10 reps. Switch sides; repeat.

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Stand with feet together, a weight in each hand, arms by sides to start. Lunge forward with left leg, bending both knees 90 degrees. [A] Push off left leg to kick left foot forward. Without touching floor, step left leg back into a reverse lunge, bending both knees 90 degrees. [B] Lean forward from waist, bring weights to ribs, and extend arms back with palms facing in. Return to start position. That’s 1 rep. Do 10 reps. Switch sides; repeat.

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“If you’re doing the right move, with the right weight, why not do it HIIT-style to get that two-for-one of strength training benefits plus cardio benefits?”

– Autumn Calabrese (@autumncalabrese), Baby2Baby supporter

Three. That’s the maximum number of high-intensity resistance training workouts to aim for in a week.

“The higher intensity requires more time for your muscles to recover between bouts,” says Heather Milton, a clinical specialist exercise physiologist at NYU Langone Sports Performance Center in New York City. “Three times per week with 48 hours of rest in between is that ideal spacing, when you can get the benefits without increasing the injury risk.”



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The refuel rule after a hard HIIT workout: 20g to 30g of protein and 70g of carbs (for a 64kg woman). “Get the full protein and half the carbs before you hit the shower, then eat the rest of the carbs at your next meal,” says Susan Kleiner, author of The New Power Eating. 

She suggests an all-natural, plain Greek yogurt with fresh fruit and pistachios to keep it easy.



Our pros reveal the resistance tools they choose for those speedy sets.

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“This really recruits your core strength,” Alexander says.

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“It’s great for building explosive power,” says coach Adam Rosante (@adamrosante), founder of

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“I match resistance tube reps to the pace of the playlist’s beat in my Body Precision class,” says Alexander. 

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“This is my new favourite,” says Alexander Charles, group fitness manager at Equinox in New York City. “Use it for swinging, jabbing, and balance moves.”

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“Try loading it with 40 percent of your body weight then sprint while pushing it; drag it back to the start line,” Adam says.

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Q: How do I ensure I’m really getting the intensity of “as many reps as possible,” where the good benefits of HIIT are?

First, kudos to you for taking ownership to make your results happen. Gold star, girl!

The tricky thing is that everything from what you eat to your mental stress can affect your physical energy, and that will dictate what your “possible” is in the weight room. 

A great way to work through this energy flux is to use a drop-set system. This means you start with challenging weights that you feel you can complete the reps with, while having another set of slightly lighter weights on standby. 

If you hit that point at which you can’t finish a set, you simply complete the remaining reps with the lighter set of weights. That way, no matter what the numbers on the dumbbells say, you’re challenging your muscle to the max and hitting that bull’s-eye high-intensity zone for results.

The key is really just listening to your body talk – that muscle-burning fatigue will tell you you’re pushing to your limit during a particular workout session.