Question: I’ve been following your HIT workout program and lost a lot of fat on my arms, shoulders, and legs but I still have some fat to lose on my abdomen and lower back. Should I add more abdominal exercises? Should I start doing high intensity interval training on my off days to burn more fat? Are there any supplements that help?
Answer: No, no, and not much. If you’re already losing fat elsewhere you are already doing what is necessary to lose your abdominal fat, it just takes longer. There are two reasons for this. The first reason is the fat in some areas is different than the fat in others. So called “stubborn” fat has less blood flow, is more sensitive to insulin, and has more of the receptors for hormones causing fat to be stored (alpha receptors) and less of the receptors for hormones causing fat to be released (beta receptors). Because of this, when your body draws on its fat stores for energy it takes less of it from these areas. The second reason is how fast you can lose fat is inversely proportional to how much fat you have. Although this limit probably varies considerably between individuals and would be affected by strength training and differences in diet, the average appears to be around thirty one kilocalories per pound of fat per day (Alpert SS. A limit on the energy transfer rate from the human fat store in hypophagia. J Theor Biol. 2005 Mar 7;233(1):1-13.). This means the less fat you have, the slower it will come off.
This means “stubborn” fat comes off more slowly on average, and since the less fat you have the slower it comes off it takes significantly longer to lose than the more “compliant” fat in other areas. To make matters worse, as you become leaner and muscle groups in other areas become better defined the contrast can make the “stubborn” areas more noticeable.
When discussing this with clients I often compare it to filling and emptying a swimming pool. Your “stubborn” fat is like the deep end of the pool, and your “compliant” fat is like the shallow end. When you fill the pool the water accumulates in the deep end first and the shallow end last. When you drain the pool the water leaves the shallow end first and the deep end last. If you want to empty out the deep end you’ve got to drain all the water. If you want to reduce the fat in “stubborn” areas, you’ve got to reduce your overall body fat significantly.
While it is possible to increase fat loss in specific body areas by exercising the underlying muscles, the difference is so incredibly small it’s not worth it (Are blood flow and lipolysis in subcutaneous adipose tissue influenced by contractions in adjacent muscles in humans? Bente Stallknecht , Flemming Dela , Jørn Wulff Helge. American Journal of Physiology – Endocrinology and Metabolism Published 1 February 2007 Vol. 292 no. 2, E394-E399 DOI: 10.1152/ajpendo.00215.2006). Trying to target “stubborn” fat with exercise is like trying to empty water from the deep end of the pool faster than the shallow end by bailing the deep end with a teaspoon.
What abdominal exercises can do is increase the strength and thickness of the abdominal muscles making them look more defined when your body fat is low enough, and they should be done for this purpose. However, you do not need to train your abdominal long or frequently as is often recommended. Like other muscle groups, if you train your abdominal muscles with a high level of intensity very little volume and frequency is required.
Performing high intensity interval training on off days not only won’t help, it can actually hurt you if you area already relatively lean. As I mentioned earlier, how fast you can lose fat is inversely proportional to the amount of fat you have. The leaner you get, the less energy you can get from your fat stores. If your calorie deficit exceeds the energy you are able to get from your fat stores the difference is going to come from glycogen, then your lean body mass. You don’t need a bigger calorie deficit as you become leaner, you need a smaller one. You can not force your body to lose fat faster by increasing activity, but you can cause yourself to lose muscle if you do too much. Accept that fat loss slows down as you get leaner, and it will take you much longer to lose the last ten pounds of fat than it took you to lose the first ten. I explain this in detail along with how to determine your starting calorie intake and adjust it for maximum fat loss in Getting Ripped.
A few supplements have been shown to help with fat loss in general, ephedrine, caffeine, DHEA, etc., and yohimbine HCL in particular may help you to lose “stubborn” fat because it blocks activation of the alpha receptors. Some people “stack” caffeine, ephedrine, and yohimbine, however I do not recommend taking ephedrine and yohimbine simultaneously, especially if you have any heart problems.