Crunches Don’t Cut Fat

Have you come across clients or exercisers who insist that the best way to carve a tight midsection is through endless repetitions of abdominal exercises? Here’s a study that will help them understand that it takes more than crunches to get that six-pack. Researchers from the department of kinesiology and health education at Southern Illinois University, Edwardsville, had one goal: to determine the effect—if any—of abdominal exercises on abdominal fat. They recruited 24 sedentary men and women, aged 18–40, and separated them into a nonexercise control group and an abdominal exercise group. Various pre- and post-intervention measures, such as body composition and abdominal endurance, were taken. The exercise group performed 2 sets of 10 repetitions of seven abdominal exercises, five times per week, for 6 weeks. At the end of the study, the exercise group showed no change in body weight, body composition or abdominal circumference. However, they were able to perform more curl-up repetitions.

“Six weeks of abdominal training alone was not sufficient to reduce abdominal subcutaneous fat and other measures of body composition,” the study authors reported. “Nevertheless, abdominal exercise training significantly improved muscular endurance to a greater extent than [in] the control group.”

The study was published in the Journal of Strength & Conditioning Research (2011; 25 [9], 2559–64.