Harley Pasternak is the personal trainer behind some of Hollywood's most impressive physiques but you won't find him promoting fad diets or grueling exercise regimes.
The Canadian fitness expert opened up to HELLO! in an exclusive chat in which he revealed the remarkably down-to-earth ways he whips the likes of Ariana Grande, Jessica Simpson and Megan Fox into tip-top shape - and the great news is you can do it too!
Speaking from his home in Los Angeles, Harley broke down his healthy approach to looking and feeling your absolute best.
WATCH: Celebrity weight loss success stories
What is the biggest thing your clients struggle with when it comes to their wellness regime?
"Time! The hours these musicians or actors work is incredible. Whether they are in the recording studio, touring or on set. They work really long hours so it's hard to fit exercise in."
How can people make more time for exercise?
"Walking is something you can do and multi-task too. So I walk to get my morning coffee. If I have a phone call to make, I do it with my earpiece in and I walk around.
"If I want to socialize I go for a walk with a friend as opposed to driving somewhere to sit down. So I think those are the easiest things to do.
Harley famously helped Jessica shed 100lbs after birth of third child
"When it comes to resistance exercise. Don't think in terms of a workout. You don't need a gym, you don't need to put aside 90 minutes for a workout.
"Sometimes it's as simple as doing one exercise a day. It could be a different exercise per day, per week. That can take as little as ten minutes a day, focusing on a different body part per day. I have a video series of ten-minute workouts. So I'm big into that."
What are two of your favorite and most effective exercise moves?
"If I were to give my clients a couple of moves to do I would say, one of them might be a hip thrust with a tricep extension at the same time as the thrust. The second would be a deadlift with a row.
"Those two moves are a combo of two moves so you are working four body parts and they are very effective."
Harley encourages a balanced healthy approach to fitness and diet
Can you still get a good workout even if you don't have much space?
"The moves that I just suggested need no more space than a coffee table. These things can be done anywhere, any time. It helps to have a pair of dumbells. But the truth is we have more than enough space almost anywhere. Even in a toilet cubicle you could do squats."
You are a huge advocate for walking, and recommend 12,000 steps a day. Why is this so important?
"If you look at the ten healthiest countries in the world - the ones with the lowest obesity, lowest heart disease extra - they have two primary things in common. One is they all walk around 11,000 steps a day.
Harley says the biggest hurdle for his clients is lack of time
The average for Americans is 4,000 steps a day. That's 25 miles a week more than the average American. So that alone is a massive component to creating a longer and healthier life."
What is the second thing?
"The second is that they have a much lower sugar diet than Americans. It's not that it's lower calorie or less food than, they just eat less sugar than Americans.
"That's a big part of it. You can live your life and enjoy your food but you should keep that sugar level down.
"Americans get 60 percent of their daily sugar before 10am. So breakfast is sort of a good place to start and be aware of how much sugar you are getting. So whether it's pastries or sugary coffees or juices. Be aware."
Harley says he encourages his clients to walk 12,000 steps a day
What would you recommend your clients eat for breakfast?
"I like to start my day with an Apple Pie Smoothie from the Body Reset Diet or a Chia Pudding Smoothie. Something with some sort of protein, fiber and healthy fat in it.
"I look for ingredients which tend to be lower in sugar. So I like berries which are high in fiber and low in sugar. I like a Greek or Icelandic style yoghurt because they are fermented a little longer and have higher protein and less sugar.
Jessica has worked with Harley for years
"Maple Hill has also just come out with zero sugar milk which is crazy because all you are left with is protein, fiber and vitamin D. It's about the healthiest thing you can have as an ingredient in breakfast.
"Focus on what you should be eating rather than what you shouldn't."
People want results and they want them fast, but it shouldn't be about quick fixes should it?
"Every day you live a healthy life you are healthier for it. I don't think there is a finish line. Every day when you go to bed ask yourself this. Did I walk 12,000 steps? Did I eat well? Did I get a good night's sleep last night? Did I unplug from my phone for at least an hour?
"If you can look yourself in the eye and say you did all of those things, you're successful."
Tell me about your collaboration with Maple Hill
"I've been a big advocate for dairy forever. I come from a scientific background. So any time I talk about food it's got to be based on some kind of scientific fundamentals. Milk is one of the best sources of protein.
Harley is one of Hollywood's most saught after celebrity trainers
"You have got whey and calcium, vitamin D and potassium. You have all of these great things and the only knock you have with dairy is lactose - which is a naturally existing sugar. Some people have a sensitivity to digesting lactose.
"So Maple Hill has figured out how to remove lactose and sugar from milk. It's super clean and it's just filtered out. So now all you are left with is protein and calcium and vitamins. It's about one of the healthiest things you can drink."
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