Harley Pasternak opts for a fist bump over a handshake.

It’s for sanitary reasons, he says, but it still adds to the Toronto-bred celebrity trainer’s cool factor.

He has golden California skin and a shiny head with hints of grey stubble, but the 41-year-old husband and father doesn’t seem a day over 21 as he dribbles and palms a basketball ahead of a workout session he’s running in partnership with Fitbit. He’s not leading drills on a court, though he still dabbles in the sport at his alma mater the University of Toronto when he’s in town.

He’s a brand ambassador for Fitbit as they launch the new Blaze and Alta editions of the popular fitness tracker. The day’s workout is “all about the butt,” the in-vogue muscle of the moment flaunted by stars like Rihanna and Kim Kardashian. Pasternak would know — he’s trained them both. The Los Angeles-based fitness guru has grown an extensive list of celebrity clientele since leaving Toronto more than a decade ago, from Kanye West and John Mayer to Amy Schumer and fellow Canuck Ellen Page.

He’s a six-time New York Times bestselling author and even has a blender named after him.

Though he lives in Los Angeles, Toronto is where his heart is, Pasternak says. His on-trend workout playlist (available on Spotify) is straight out of a hip-hop night at a King West nightclub, from Fetty Wap to Toronto’s own Drake, whose “Jumpman” plays over the speakers (his young daughter knows all the lyrics, he jokes) at the Financial District’s Toronto Athletic Club as he leads a group of bloggers and content editors through a posterior blasting routine.

The group takes selfies and films Snapchat stories between sets of body weight lunges and squats. Pasternak lightly admonishes them for using their smartphones. It’s easy to wonder if he’s said the same to queen-of-selfies Kim Kardashian during a workout session. Anyone who follows the reality star on Snapchat might have spotted a shot of her other trainer Gunnar Peterson earlier this spring.

Between one minute sets of lunges and squats (one leg or side at a time), Pasternak doesn’t let his trainees stand around or post shots to Instagram. Instead, light jogging on the spot as though using a jump rope is encouraged. Pasternak doesn’t quit and neither do you.

Harley Pasternak’s moves

The following Star-tested workout routine from the celeb trainer is simple, but should be performed at high intensity.

Reverse lunge

The leg blasting begins with the reverse lunge movement, one leg at a time for a minute each.

How to: take a large step backward, lowering the hips until the front leg is parallel with the floor. The forward lunge can be difficult for people with knee problems, says Pasternak, so this variation is ideal.

Skater lunge

After a short rest of jogging on spot, a variation of the reverse lunge called the skater lunge asks trainees to bring out their inner speed skater.

How to: Step one leg behind and across the opposite leg and lower your hips into a lunge, keeping your balance.

Side step squat

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The average squat always works, but Pasternak doesn’t do anything average.

How to: Take a step to one side and lower the hips, back straight, into a deep squat.

Walking lunge

All of these exercises can be done with just a small amount of space. You’ll need a bit more for these next two. Clear the living room floor or turn your backyard into a gym.

How to: Take a long step forward, lowering the opposite knee to the ground. Lunge across the space for 8-10 paces before breaking.

Leap frog

As fun as animal-inspired workouts sound, the leap frog is a demanding squat variation.

How to: Jump like a frog across a room, leaping off two legs and landing in a deep squat position.

Jump-off

Sometimes a little friendly competition is healthy. Face off with a friend to cap off Pasternak’s leg blasting workout before cooling down with some jogging on the spot.

How to: Lock eyes with a workout buddy. Go from a deep squat position, back straight, to a small standing jump, and back down into a deep squat. Do as many as you can.

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