Bad stretching can defeat good design

May 10, 2012
The Boston Consulting Group recently predicted that reshoring of manufacturing operations to the U. S. could create as many as 3 million jobs by the end of this decade

The Boston Consulting Group recently predicted that reshoring of manufacturing operations to the U. S. could create as many as 3 million jobs by the end of this decade. Problem is, indications are that this welcome trend could lead to a severe shortage of skilled workers. Virtually every person on a factory floor will be valuable and hard to replace.

All the more reason, then, to take steps that minimize the possibility of worker injuries. But sometimes equipment designs can only do so much to promote an injury-free workplace. Operational norms can be just as important for keeping workers well and on the job.

This is particularly true for an aging workforce, a fact of life in the U. S. with its Baby Boomers. As people get older, they need to spend more time loosening up and stretching before exercising. That is why many companies conduct calisthenics, on the clock, for their factory workers. Too many of us put ourselves in highenergy situations without taking the proper precautions.

A story helps illustrate the point. While in college many years ago, I was a skydiver. During my 26th jump on a December morning in Minnesota (ground temperature 0°F), and without any stretching before boarding the aircraft, I broke my ankle on landing. When I healed and the weather warmed up, I jumped again into a plowed field and broke my foot. This time I had done a few minutes of stretching first.

Since then, I have always stretched and loosened up, but on occasion would still injure myself. Recently I found out why: What I was doing was exactly wrong. Bill Holcomb, Ph.D., professor of Athletic Training at the University of Nevada, Las Vegas, set me straight. Extensive research shows that the worst thing one can do is stretch cold muscles. Holcomb has found that static stretches (meaning the kind where you hold the stretch before a workout or competition) actually reduce strength, power, and performance.

He has come up with several tips on proper stretching techniques. Among them: Always warm up first. Stretch, but not when muscles are cold. Do 5 minutes of brisk walking or slow jogging. “Warming up increases blood flow, which increases the temperature in the muscle, which makes the collagen fibers more elastic like a rubber band,” he explains.

After warming up, do dynamic, not static, stretches. Dynamic stretching means slow, controlled movements rather than remaining still and holding a stretch. These include a goose-step march: Slowly lift your leg straight out in front of you, alternating as you walk with your normal stride length. This is also an effective hamstring stretch. Also do knee lifts: Bring your knees up to or close to your chest as you jog or walk. Finally, try a butt-kick: As you jog or walk, bend one knee and lift it behind you as though you were trying to kick yourself in the butt.

And never stretch to the point of pain. Forget the phrase, “no pain, no gain.”

My stepson and son-in-law both began to subscribe to these principles once they suffered severe Achilles injuries after doing static stretching exercises. My stepson suffered his Achilles tendon injury chasing a fly ball. He now coaches his son’s soccer team and has his players do proper warm-ups before each soccer practice and game. My son-in-law tore his Achilles tendon taking a first step in a touch-football game. Now even before something as mundane as bowling, he goes through Holcomb’s warm-up and stretching program.

The lesson: Workers should warm up and stretch before any activity where they may be injured, but they should do it properly.

— Lanny Berke

Lanny Berke is a registered professional engineer and Certified Safety Professional involved in forensic engineering since 1972. Got a question about safety? You can reach Lanny at [email protected].

Edited by Leland Teschler

© 2012 Penton Media, Inc.

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