I asked a bunch of experts for one exercise that would offer the greatest value for time spent. I was hoping they would say, “Eat chocolate, in moderate quantities, throughout the day.” Instead, they said, “Squat.” So I do, and so can you.

Squats don’t require specialized equipment. They can be done anywhere: while waiting for the tea to brew; while waiting for the copy machine to warm up; while speaking on the phone.

Squats use some of the most important—and biggest—muscle groups, such as those in the buttocks and the upper thigh. Regular squats help people adapt to ageing better. If you look at octogenarians, the one thing they have difficulty with is getting up from a chair without help. Squats directly help this activity.

The trick is to do it right. Keep your feet one shoulder-width apart. Fold your arms in front of you. Then, go down with your back straight. The way to do this is by pushing out your butt. Or by gazing upwards. In the beginning, you go down as much as you can without kneeling over. The goal is to squat low enough so that your thighs are parallel to the ground, as if you are sitting on a chair that doesn’t exist. Lift yourself up; go down; lift yourself up. That’s it. Doing squats every day strengthens these muscles and can help you lift yourself up, quite literally, in your golden years.

Now the twist. No matter how much you exercise, there are times when you can do nothing; when you just have to sit and listen. Or so you think. Allow me to shatter that little misconception.

Think about when an unexpected guest drops in. You haven’t seen Uncle Fernandes or Aunty Malhotra in years and after half an hour of listening to his old army stories, you realize why you made sure you didn’t meet him. What are you going to do? You cannot get up and leave. Think of a classical music concert or a lecture. Think of those long meetings where you have to just sit and listen to people drone on and on. All you can do is sit still and listen. Or maybe not.

Now, you may be one of those people who knows how to handle a long Western classical music concert; you know exactly when a symphony is supposed to soar; which year Mozart wrote his piano concertos; and what mood he was in when he wrote the fifth movement. I am not. After an hour of undivided attention to the orchestra, I begin fiddling.

Knee curls are great for occasions when you are forced to sit in one place. Make sure your foot is straight. I rest my foot on the chair in front of me. Then, I tighten my knee, so it looks like I am pulling up my knee cap. I hold this position for 15 seconds and then loosen. That’s it. Do 15 repetitions of this movement, first on one leg and then the other. Slowly increase the count to 35.

This strengthens the knee joint and gives you something to do during a long classical music concert or a lecture. I am doing it now as I sit on my desk and type. All it requires is space underneath your table to stretch your leg forward. Simply straighten your feet by resting your ankles on the floor and do the knee curl. Better yet, lift your feet off the floor and do it—if possible.

Squat and curl during your spare time. It won’t seem onerous and will actually benefit you in the long term.

Shoba Narayan’s curly knees match her curly hair. Write to her with your tips, tricks and short cuts. She blogs at Shobanarayan.com, tweets at @shobanarayan and Instagrams at #shobanarayan