Sources: Kasee Hildenbrand at 785-532-3211 or khilden@k-state.edu
and professor Larry Noble at 785-532-6979 or lnoble@k-state.edu
News release prepared by: Kay Garrett

Wednesday, December 4, 2002

STRONG ABS DON'T REQUIRE EXERCISE MACHINES, RESEARCH SHOWS

MANHATTAN -- If all you want for Christmas is a great set of abs, then a recent study of ab machine effectiveness is just for you.

Exercise scientists at Kansas State University found that the unassisted crunch or sit-up is as good a workout for the abdominal muscles as any you'd get using typical abdominal exercise equipment on the market now.

Consumer appetite for abdominal exercise machines has gone biggie-size in recent years: in 1998, according to the Sports Business Research Network, Americans spent $115 million on ab machines alone, with sales rising. In fact, says K-State biomechanics professor Larry Noble, ab machine sales have been one of the few components of the overall sports equipment market that's still growing.

What drives this market? It's about equal parts health concern and vanity. Lower back injuries, for example, are largely the result of weak abdominal musculature, and it's a costly health issue. In any given year, half the U.S. population experiences lower back pain. Direct medical costs for low back pain exceeded $24 billion in 1990.

Beyond that, the crunch is on, so to speak, to have a flat stomach. There's been no scientific evaluation of various claims of equipment effectiveness, say the K-State researchers. Infomercials have been the sole source of product information.

Noble and graduate student Kasee Hildenbrand, also a certified athletic trainer, conducted the research. Hildenbrand measured electrical activity in the belly of the abdominal muscles of each participant during exercise. She detected no significant differences in muscle electrical activity.

The group of very fit K-State students performed repetitions of unassisted crunches as well as abdominal exercises on the Abroller, Abslide and Fit-ball -- devices that represent the broad categories of ab exercise equipment on the market now.

"We're confident in saying you can do a crunch without equipment and get the same benefit as if you purchase any of these categories of equipment," Hildenbrand said. Some people are more motivated to exercise when they use equipment, she noted. The choice to equip or not to equip is personal.

"Our results suggest that doing abdominal strengthening exercises with equipment does not elicit any greater muscle activity of the targeted rectus abdominus muscle than if you perform traditional abdominal crunches," she and Noble said.

The researchers looked at another muscle group, the rectus femoris, a hip flexor muscle and not technically an abdominal muscle. They included it because it is one of the most powerful muscles used in bending, and in the typical American population the rectus femoris is more powerful than the rectus abdominus.

When abdominal exercises are done incorrectly, it's the rectus femoris that gets the workout instead of rectus abdominus. To perform a proper crunch that works the rectus abdominus, athletic trainer Hildenbrand instructs: lie on your back, knees bent, feet unanchored, arms behind your head resting on the neck. Crunch forward till your shoulder blades are off the mat or floor.

"Our guts are a real problem," Hildenbrand said. "As Americans become a more obese and sedentary population, we're getting ab messages about lower back health and from the popular culture that says a thin belly is in."

She hopes people pay attention to those lower back health concerns. Research has found over and over that the abdominal musculature is key in preventing or correcting problems associated with lower back pain.

"If the abs are strong and doing their job, they tip the pelvis backward, which straightens the lower back so a person is in correct alignment," she said. Strong abs counteract the strong hip flexors. The whole point of strong abs is to keep the pelvis in alignment so it supports the spine in correct alignment.

"Even if a person is overweight or has a fat belly, it's still very important to have strong abdominal muscles, she adds. Getting rid of a fat belly will take more than ab exercises, however. That takes a change of diet and an exercise program that includes functional exercises like walking, running, swinging a racket, or swimming, exercises that move, twist and flex the muscles that wrap around the body's core.

"In other words, don't bank your entire abdominal strength on doing crunches," Hildenbrand says. "Crunches are a very important part of the picture, but you also will need to twist the body functionally to keep it strong."

Hildenbrand presented the poster, "Abdominal Muscle Activity While Performing Trunk Flexion Exercises Using the Abroller, Abslide, Fit-ball and Conventionally Performed Trunk Curls," in June 2002 at the National Athletic Trainers Conference in Dallas. The poster had won second prize in October 2001 at the regional conference of the American College of Sports Medicine.

HOMETOWN CONNECTION

Kasee Hildenbrand is a 1994 graduate of Cheney (Wash.) High School. She is the daughter of Daniel and Pamela Melchior, Stoughton Road, Cheney, Wash.. She earned her undergraduate degree in sports medicine and physical education in 1998 from Whitworth College, Spokane, Wash.

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