MICHAEL CHIKLIS HAS played tough cops in shows like The Shield and a granite-strong superhero in The Fantastic Four, but the most difficult physical challenge the actor has faced over a long career might just have been playing a regular, real-life guy. That regular guy did something remarkable, however—Chiklis’s most recent film, The Senior, is about 59-year-old Mike Flynt, who suited up for college football as the oldest player in the NCAA.

Stepping into the shoes of this character wasn’t a stretch for Chiklis, who is now 62—he says he was the captain of his football team in high school, so he has the background—but getting in shape for the film well after 50 was a trial. The actor did “about 90 percent” of the football action on screen, so he needed to be able to do more than just look the part. He had to be able to move, too.

How did he do it? A dedicated strength and conditioning plan (and plenty of focused warm-up and mobility). Chiklis stacked up full-body training sessions to prep his body to get into football shape. He did more than just gym training, however; Chiklis says he would often spent 40 minutes in the pool jogging and walked 10,000 steps to raise up his general activity levels.

For some people trying to lose weight, they might find that they’ve plateaued and wonder if there is anything they can add to their workout routine to jumpstart their metabolism. Enjoying a high-intensity interval training (HIIT) workout a handful of days per week can be just the thing that works.

“If you’re looking to be more explosive, athletic or build muscle, HIIT workouts are best suited to help you do that,” Rafique “Flex” Cabral previously told TODAY.com.

Trainer Tip of the Day: HIIT Workouts 3 Days a Week Boosts Metabolism

A HIIT workout focuses on brief moments of super-intense activity with rest periods sprinkled between the exercise. While the high energy exertion occurs in quick bursts — often 30 to 45 seconds, with rest in between — it demands more of the muscles. This type of exercise builds and maintains lean muscle mass, which can help with weight loss.

“Maintaining a routine that involves HIIT training three to four times a week will help compound that post-workout effect on your metabolism,” Cabral said.

HIIT sparks something called excess post-exercise oxygen consumption (EPOC), which enables people to burn calories even after their workout ends. The American Council on Exercise says that HIIT works best for kickstarting EPOC.

“You will produce an after-burn effects with 25% more calories burned post-workout compared to going for a walk or a run,” Lisa Reed, a performance coach and owner of Lisa Reed Fitness, previously told TODAY.com.

Why It Matters

HIIT’s impact on people’s metabolism lingers for some time — Reed estimates it bolsters metabolism up to 10% for three days after a workout.

Having lean muscle mass helps with weight loss but also promotes healthy aging. People with more lean muscle are less likely to experience falls and engage in their daily activities with ease.

How to Get Started

Dedicating even 20 minutes three times a week to a HIIT workout can lead to boosted metabolism and weight loss. Workouts can be customized to exercise preference and the equipment people have handy.

“You can also keep things interesting by switching up the sequence or swapping out different exercises from strength to high-intensity movement,” Reed says. “HIIT workouts are an excellent way to increase your workout intensity in a short amount of time — 20 minutes or less.”

TODAY’s Expert Tip of the Day series is all about simple strategies to make life a little easier. Every Monday through Friday, different qualified experts share their best advice on diet, fitness, heart health, mental wellness and more.

Published in Nature, the study investigated which internal factors—if any—influence our desire to exercise. The researchers analyzed a wide range of factors, including genome sequences, gut bacterial species, and bloodstream metabolites, looking for any possible connections between these factors and daily voluntary wheel running and endurance.