It's State Fair time — so what better time to introduce readers to the Hydraulic Hand Dynamometer?

I'd never heard of such a contraption until this week, but it sounds like something we'd see along the hot and crowded avenues of the Great Minnesota Get-Together, tucked perhaps inside the grandstand with a leather-skinned salesman barking, "Step right up! Test your skill!"

In fact, the device is more likely to be found in a sports medicine clinic. Still, we should all step right up, millennial men, in particular. The effort could be lifesaving.

Research suggests that men ages 20 to 34 are losing ground in upper-body strength, with weaker hands and arms than men in the same age group 30 years ago.

This deterioration was calculated by using hand dynamometers and pinch gauges to measure grip and pinch strength on a sample of 237 "healthy millennials."

The average young man, according to the study in the Journal of Hand Therapy, was able to apply 98 pounds of force when gripping something with his right hand, compared with the average man in 1985 who could grip with 117 pounds of force.

Yawn. So what?

Here's what: Grip strength is a powerful predictor of life expectancy.

A study of nearly 140,000 adults in 17 countries, published in the Lancet in 2015, revealed that grip strength is an even stronger predictor of death than systolic blood pressure.

After adjusting for other factors, Lancet study author Dr. Darryl Leong found that each 11-pound decrease in grip strength was linked to a 16 percent increase in deaths, a 17 percent increase in cardiovascular and non-cardiovascular mortality, and a 9 percent increase in the risk of stroke.

The findings were not surprising to Dr. Sanjeev Kakar, a Mayo Clinic orthopedic surgeon who specializes in the hand and upper extremities. He frequently notes evidence of a decrease in strength between manual and non-manual workers.

"It's very apparent in today's world that a lot more people are doing office-type, sedentary work and using their mobile devices," he said.

Still, he takes the study's findings with a grain of salt, noting that the cohort was made up of university students who, let's be honest, aren't likely to be found baling hay after class.

His biggest worry is that young men are all thumbs, due to texting skills.

Aside from more repetitive strain injuries and tendinitis, Kakar is seeing an increase in "thumb pain" among young men. "There's a lot more of this than 20 years ago," he said.

If left untreated, young people could lose dexterity, to the point of being unable to perform simple daily living activities, such as opening a jar or twisting a doorknob.

Kakar advises the use of voice software in lieu of texting. He also recommends that office workers improve their cubicle ergonomics, with better sitting posture and an ergonomic-friendly mouse.

He'd also like parents to limit their kids' time on their devices. Good luck with that.

"We have good surgical treatments," he said, "but the goal is always to avoid that."

Women pump it up

Among women, the 30-year difference wasn't nearly as dramatic, most likely because women were less likely to be doing manual labor in the previous time frame.

The average right-hand grip force of young women was roughly the same in both decades, about 75 pounds. The outliers were millennial women ages 30 to 34, who were stronger than their mothers' generation, squeezing 98 pounds of force.

Anna Zawadski, co-founder of Kingfield Endurance, a weight training, body pump and personal training studio in Minneapolis' Uptown neighborhood, was at first surprised by the study regarding young males. Then she thought about it.

"It makes sense," said Zawadski, an Ironman finisher in 2014. "Men are powered by being behind their computer. And we have predominantly women at our gym, one male for every three females."

Part of the gender shift, she said, is a growing societal support for young women who want to "be stronger, better at their sport, who want to avoid injury and recover faster.

"They're definitely stronger than their mothers," Zawadski said, although women 50 and older also are seeking her out for strength training.

"We are finding our stride," she said of women. "I like to say that strong is the new skinny. Women are saying, 'I can get stronger, I can compete in these events.' "

Amanda Dekan, senior instructor for REI's Outdoor School, has a great solution for anyone interested in improving longevity with grip and pinch strength: rock-climbing.

"Climbing builds grip and pinch strength," said Dekan.

Basketball, hockey and baseball also work on grip strength, she noted. And yoga.

Just choose something.

When you build upper-body strength, Dekan said, "you carry yourself differently. You feel more confident. You have more endorphins."

And, most important at State Fair time, you can open that pickle jar.

gail.rosenblum@startribune.com 612-673-7350 • Twitter: @grosenblum