How Test Your Strength in 30 Seconds

If you want to stay healthy as you age, experts say you have to keep moving with a mix of cardio, strength and balance training. But there’s another critical element, one that doesn’t get as much attention. It’s what gives you the ability to toss a heavy trash bag into a can or lift a suitcase into an overhead compartment.

It’s called power, and it’s never too early (or late) to start building it.

Experts define power as the ability to apply force rapidly — using fast-twitch muscle fibers in short, explosive bursts. Strength allows you to lower into a chair, power gets you back up. If you trip and stumble, power allows you to quickly recover and avoid a fall.

Two years ago, Beverly Coleman, a 71-year-old bridal store employee in Lexington, Ky., noticed her waning power when she struggled to hoist a 25-pound bag of dog food across her threshold into her house. “I’d have to drag them in or ask my son for help,” she said.

Like strength, power is a “use it or lose it” ability that can disappear quickly. While strength declines around 1 to 3 percent annually after the age of 55 if you’re not strength training, power disappears at a rate almost double that.

“Often, we don’t realize we’ve lost power until it’s gone,” said Ali Hartman, a doctor of physical therapy based in North Carolina who works with seniors.

Dustin Jones, a Kentucky-based doctor of physical therapy, said that when you lose power, single tasks often feel draining. If you struggle to run up a flight of stairs or are unable to quickly step up onto a curb at a busy intersection, that’s a lack of power.

But with the right exercises, you can prevent this — or restore power you’ve lost. And depending on your fitness level, you can make significant progress in as little as a month or two.

Take the power test.

How do you know if you are losing power? One of the most time-tested ways to tell is the sit-to-stand test, which also gauges one’s risk for falling. Sit in a chair with a straight back and no arm rests and cross your arms over your chest, resting your hands on your shoulders, feet flat on the floor. Start a timer for 30 seconds and count how many times you can move from sitting to standing.

Men over 65 should be able to do 12 or more; women over 65 should do 11 or more. If you score below that, you may be low on power.

While there is no defined standard for younger adults, one study suggested that men under 60 should be able to complete at least 17 repetitions and women 15.

Building power can happen quickly, but requires weights.

If your score indicates that you have less power than you should, it’s important to build it back. And it doesn’t have to take too long. (Here is a workout for building power.)

Ms. Colman eventually started taking fitness classes for people over 55. Strength can be built with just body-weight exercises, but maintaining or increasing power almost always requires using weights. In Ms. Coleman’s case, that meant starting small: She used five-pound dumbbells to master moves like snatches, and an 18-pound empty barbell for deadlifts. She then steadily increased the weights.

Before long, she could climb five flights of stairs without stopping, when a single flight once challenged her. After a couple of months, that same bag of dog food she had struggled to drag into the house felt “like a loaf of bread,” Ms. Coleman said. “By my birthday, about six months later, I lifted 105 pounds in the gym.”

The idea of lifting, pushing and pulling heavy weights makes many people, especially those new to fitness, nervous. But with consistency, and starting gently, it’s not only possible, but crucial.

In fact, “under-dosing” on weights is more threatening to your quality of life than avoiding weights, said Dr. Jones. “When we handle older adults with kid gloves and assume they’re not capable of certain moves and weights, we’re opening up the door to continued decline.”

Starting off light is fine, said Dr. Ronald E. Michalak, an orthopedic surgeon from New Hampshire. “But if you don’t ramp up from there, you can’t achieve what you need.”

Coleman continues her classes, and now her life includes activities like hiking, kayaking and even running races at the senior games. “I was scared to death when I began, but now I’m helping others lift heavy things at the Sam’s Club.”

“It doesn’t take much to build power,” said Dr. Michalak, “but you must be consistent and stick with it for the rest of your life.”

Amanda Loudin is a freelance writer covering health and science.