Waging war on weakness
Using dynamometer readings, the generally accepted cutoffs for low grip strength are 26 kg for an adult male and 16 kg for a female.
But that’s way too simple, Dr. Peterson said.
For one thing, age matters. Grip strength typically peaks for men in their late 20s and declines rapidly in middle age and beyond. For women, it plateaus in their 20s and gently declines until their 50s. So, at minimum, the age-based standards included with a dynamometer should be consulted.
Another caveat: Dr. Peterson said grip strength tests aren’t very meaningful for people who actively train for strength, though he suggests dedicated athletes make up a relatively small percentage of the population – even as low as 10%.
The size of the person taking the test is also important.
“You absolutely must account for body mass in the context of understanding how grip strength, or any strength measure, is reflective of health and function,” Dr. Peterson said.
To calculate strength-weight ratio, which Dr. Peterson calls “normalized grip strength,” divide grip strength in kilograms by body weight in kilograms. For men, a ratio greater than 0.70 puts them in the higher percentiles. For women it’s 0.50.
And if the results suggest that the person in question is objectively weak? “For me, that’s easy,” Dr. Peterson said. “They need to exercise.”
Common sense suggests doing a lot of forearm exercises for grip strength. Not so, said Dr. Peterson. The strength of hand and forearm muscles reflects what they can do along with all other muscles moving together.
A 2019 study found that, for older adults, a variety of exercise programs can lead to modest but meaningful increases in participants’ grip strength – and they don’t necessarily have to include actual gripping exercises. The programs ranged from tai chi to water aerobics to walking, stretching, and all kinds of resistance training.
Dr. Peterson’s advice to everyone is pretty straightforward: Get stronger. It doesn’t really matter how you do it, or how much strength you ultimately gain. Even a little more strength means a little less weakness, and a little more life.
A version of this article first appeared on Medscape.com.