‘Ab’ Machines Best At Trimming Down Your Wallet Scientists Say Crunch Devices Don’t Improve Bent-Leg Sit-Ups

Want to flatten that tummy? Lose those love handles? Cultivate a washboard abdomen? If you have not already invested in an “ab” device, you might just save your money, get down on the floor and start doing some crunches to get as good an effect as that from any of the popular devices.

A new study sponsored by the American Council on Exercise has shown that old-fashioned bent-leg sit-ups are as effective as popular abdominal exercise gadgets in working those midriff muscles.

The study, directed by Dr. William C. Whiting, a specialist in biomechanics at California State University in Northridge, found no overall advantage to the devices, which cost from $75 to $120, unless their purchase motivates someone to adopt and stick with a fitness program.

Whiting and his collaborators at Occidental College in Los Angeles, took strong issue with “infomercial” assertions that ab devices could help someone shed “10 pounds in 10 days” or “four to six inches in a month.”

Whiting said that such advertising claims were based, not on the workout done using the devices, but on the nutrition and aerobic exercise program outlined in the brochures that accompany them.

Crunches, whether done on one’s own or aided by a device, do not use enough calories to result in weight loss and cannot “spot reduce” accumulations of body fat, the researchers said in their report in the current issue of ACE FitnessMatters, the council’s bimonthly publication.

In theory, when doing crunches, the thigh muscles should not contract and the neck muscles should contract as little as possible. One claim made for ab devices is that they help to minimize strain on the neck.

But when participants did an oblique crunch, one of the devices, Abworks by Nordic Track, actually resulted in much greater neck strain than the unaided crunch and those done with the other devices tested, the researchers reported.

This device also resulted in greater involvement of the thigh muscles during an oblique crunch, according to the study.

In doing a basic crunch with hands behind the head, the study showed there was slightly less neck strain associated with two devices - the Ab Roller Plus made by Quantum North America and the AB Trainer made by Precise.

But the researchers concluded that overall there was “no apparent benefit or detriment” to the devices.