Paul Mescal, 'Gladiator II' and how genes affect our fitness

Paul Mescal upped his gym game while prepping for "Gladiator II" – but not in as intense a way you might think.

The actor told the BBC he only spent 45 minutes in the gym each day. That's not exactly easy, though it's not the hours and hours you usually hear about when training for a role of this nature. "I was lucky that I had a background in sport before we started this," he says, likely referencing his days playing Gaelic football, so "it wasn't going into totally new territory." He also said he lucked out thanks to his genetics.

Commenters were quick to weigh in on Mescal's statements on TikTok: "The physique he had in 'Gladiator' is not that different from any regular, consistent gym-goer with good diet and genetics. It’s quite realistic and achievable." "45 mins training with high intensity is actually all you need." "Very realistic answer."

But are they right? What is the optimal fitness regimen – and how much are our genetics a factor? The truth is that while there are general exercise and nutrition guidelines for everyone, your genetics will determine how much you need to tweak your routine.

You might ask: "'Well, am I a lost cause because of my genetics?' The answer is no, but you may have to work differently to achieve the same result," says Stephen Clark, physical therapist, athletic trainer and Clinical Innovation Director for Confluent Health.

How much do you need to work out each week?

The Centers for Disease Control and Prevention recommends adults get at least 150 minutes of a moderate-intensity workout every week. That rounds out to 30 minutes per day over five days per week. It's also suggested adults practice two days of muscle-strengthening activity every week.

Mescal's 45-minute routine per day, for example, "is a level much higher than the minimum recommended," says Tiago V. Barreira, associate professor at Syracuse University's Falk College of Sport and Human Dynamics. "It would be difficult for someone to start at this level, but it would not be out of the question for someone already doing some level of physical activity."

New research also indicates your body may also respond well to exercise based on past physical activity. "There is some evidence for skeletal muscle 'memory,' or the ability for muscle to grow faster than normal due to prior training exposure," says Marni Boppart, professor in the College of Applied Health Sciences at the University of Illinois Urbana-Champaign.

Plus: "According to a systematic review from the Journal of Sports Science and Medicine, there have been 30 genetic markers associated with one's ability to efficiently lose fat," says physical therapist Femi Betiku. "Also there are 24 genetic markers for someone to effectively build muscles with a specific exercise regimen."

We all know physical fitness is crucial. But how many days weekly should you work out?

'A huge bummer'

Not everyone with a fervent fitness habit, though, is going to see results like Mescal. And part of that indeed has to do with genetics and weight distribution. While you can certainly amp up the amount of muscle mass in a part of your body by focusing on it during workouts, you can't necessarily burn fat in that area at the same time.

"When you do crunches, you'll strengthen those ab muscles, but where you lose fat on your body will be heavily dictated by genetics," says Sam Leicht, creator of queer fitness app Pridefit, "a huge bummer for people trying to lose fat in specific areas."

Celebrities, too, will generally have access to high-quality trainers and nutritionists – something not as accessible to the public. "The average person would get huge benefits from lifting weights for 45 minutes a day," says Michael Joseph Gross, author of the forthcoming "Stronger: The Untold Story of Muscle in Our Lives," "the benefits just wouldn’t be so visible."

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'All exercise should be added gradually'

Those looking to change up their exercise habits should start small – strength training a few hours per week, stepping outside for a 40-minute walk and practicing a healthy diet, adds Leicht.

Plus, "it’s important to know that someone’s exercise intensity, duration and effort should match their goals," Clark says. "So, if your goal is not to look like a gladiator, your effort shouldn’t be the same. All exercise should be added gradually and at rates that your body can handle as to not increase injury risk."

This article originally appeared on USA TODAY: Paul Mescal, 'Gladiator II' and how genes affect workouts