Tell me if this sounds familiar:
"I just want to get rid of the fat around my stomach, so I'm just going to do sit-ups"
"I just want skinnier legs, so I'll do lunges and squats"
A lot of us have parts of our body that we would like to be smaller - for most it's their belly or legs. It sounds reasonable that if you have a some extra weight hanging around your waist that doing sit-ups and crunches would get rid of it right? wrong.
This is a fairly common misconception about working out and it's call the spot reduction myth. It would be great if it were true, but the unfortunate reality is that the way your body uses it's fat stores in a set way. Read this excerpt from ACSM's health and fitness journal:
The concept of spot reducing is a complete myth. No exercise will eliminate fat from a specific area of the body, just as no change in your level of caloric intake will guarantee that the fat will melt away in the area of the body you most want to address. As a rule, the pattern in which you lose body fat is genetically predetermined. (Peterson J., 2008)
What this means is that the way your body stores and uses up fat is largely determined by your genetic make up. This is why, for example, if you exercise with a friend they my lost the fat around their belly while you lose inches of your chest or thighs - even though you are doing the exact same routine.
Doing sit-ups or lunges will only work the muscles underneath the fat. The fat itself will not be used until the body deems in necessary to use those fat stores, and this will not occur by doing sit-ups alone (unless you do hundreds or thousands and the body burns through its carbs).
So how do you get rid of that fat? A combination of diet and exercise (like interval training) will work best. There are numerous online resources to help. livestrong.com has many helpful tools and a forum for support and advice.
What do you think about spot reduction? Let me know in the comments section.
Peterson, J. (2008). Ten Common Mistakes Individuals Who Are Trying to Lose Weight Make. ACSM's Health & Fitness Journal, 12(6), p. 52.