Hard to fit exercise into your day? Then, maybe this workout is for you. It covers everything you need — from cardio to strength training to stretching.

"You can get a fantastic workout in 22 minutes," says Tim Church. He's a physician and researcher who has spent his career studying exercise.

Why 22 minutes? Compared with 1960, Americans today burn about 140 fewer calories, on average, per day because of our sedentary jobs. To offset the damages of sitting, we need to move. The latest recommendations call for at least 150 minutes of moderate-intensity exercise per week to maintain good health. If you divide 150 minutes by seven days a week, that's 22 minutes a day.

With the help of certified fitness trainer Bryant Johnson, whose high-profile clients include Supreme Court Justice Ruth Bader Ginsburg, we break down this workout into 10 minutes of cardio, 8 minutes of weight training and 4 minutes of stretching. The best part? All the exercises can be done at home — no special equipment needed.

Only 10 minutes of cardio? Yep, I was skeptical, too. But here's the hack: Whether you're on a treadmill, an elliptical, or exercising outside, say goodbye to your steady pace. Instead, think intervals, or high-intensity interval training. You'll start out slow, then build in bursts of intense aerobic activity that push up your heart rate. I like to alternate between one minute of cycling as hard as I can, followed by one minute at a more leisurely pace. Then, I repeat. (You can also try 20- or 30-second sprints.)

Johnson compares interval training to driving a car. Cars burn more fuel with the stop-go, stop-go of city driving. On the highway, cruising at a steady pace, you don't burn as much fuel. So, think of interval training as city miles — you're burning more fuel, or calories.

One study found that, compared with people who worked out at a steady pace, those who did interval training on stationary bikes as part of a four-month study were able to lose more weight from fewer minutes of exercise.

"You're getting more benefit," explains Church. "HIIT [high-intensity interval training] helps you have a very efficient workout. You're stimulating more physiological pathways and you're stimulating more muscles."

Our workout starts with 5 minutes of cardio, then moves on to weight training. Add another 5 minutes of cardio before ending with stretching.

After cardio, weight training is the next essential component of our workout. Bryant Johnson has built in repetitions of three simple exercises. We start with pushups or planks. Then we move on to squats, which he demonstrates here.

If you listen to our LifeKit podcast on exercise, you'll hear me struggle through the pistol squats (squats performed with one leg lifted off the ground) and the pushups. What I realized is that I've been focusing too much on cardio, and I don't have as much strength as I thought. When I put Morning Edition host Rachel Martin through this same workout, she had a similar realization: The pistol squats were tough for her, too, even though she's an avid runner.

Then, for the upper body and chest, Bryant suggests a rowing-like exercise, which he also demonstrates here. You can use a towel, belt or resistance band.

We did three weight training exercises in a circuit: 12 repetitions each of squats, rows and pushups (not pictured). You can do standard pushups, or if you're just starting out, try standing pushups against a wall. Repeat this circuit — squats, rows and pushups — three times.

Weight training becomes even more important the older we get. "From age 40 or 50 on, you lose 1-2 percent of your muscle mass per year," Church says. "Maintaining muscle mass and strength is absolutely critical to quality of life, to healthy aging." He says it's the ultimate use it or lose it.

This workout ends with 4 minutes of stretching, which for me is a supplement to a yoga practice. Why is it important to make time to stretch? "It's a way of calming the nervous system down," Johnson says.

To inspire all those who are tempted to skip stretching, Johnson says you want to aim to be a bamboo tree, not an oak tree. "Which type [of tree] is the strongest?" he asks. Under pressure, an oak may snap, whereas a bamboo tree will sway and bend. "The more flexible you are, the stronger you are."

Now that you've got the routine, here's our advice: repeat daily.

Church says the benefits of working out are innumerable. Not only does it help fend off disease, it makes our bodies stronger and our minds clearer.

"I've spent my whole career studying exercise, and I'm absolutely convinced that 95 percent of the benefits of exercise are above the shoulders," Church says. Exercise can help reduce anxiety and depression. "There are so many benefits to the brain, and each year we learn more."

Copyright NPR 2020.