Many women come to me asking for a program that will tone up their thighs, buttocks, and the back of their arms. In reality, what they are asking for is to remove fat from these areas. Is it really possible to do so with specific resistance training exercises? The answer is no, but…
American researchers (1) have discovered that by only performing localized resistance exercises, the body fat percentage of the target area does not change. These scientists studied the effect of arms exercises (biceps-triceps) on the actual quantity of fat and the size of fat cells in this particular area of the body. In this study, only one arm was exercised, the other remaining inactive. After 12 weeks, researchers observed no difference in the quantity of fat between both arms. However, this does not mean it is impossible to tone up. Indeed, the thickness of the fat layer (measured with a calliper) had decreased for the arm that had been exercised. Resistance training allows muscles to grow. These in turn apply pressure on the fat layer, and the arm becomes firmer.
Why doesn’t the target area draw energy from the nearby fat reserves? Because there is no connection between fat and muscles. When we need energy, the body releases fatty acids in the bloodstream, which can originate from any part of the body. The muscle can then receive these fatty acids and use them as energy. In short, when the aim is to tone up, resistance training is used to grow muscles rather than to lower body fat.
A word of caution is needed here. Although I mentioned that the muscles will grow, this does not mean you will end up with “big arms”. You arm will become firmer without really being bigger. Here is what happens. The picture below represents an inside view of your arm. On the left is an untrained arm, the blue representing muscle mass, and the beige representing fat. On the right, we can see that after a training program, the muscle’s volume has increased. Observe that both pictures are of the same size. Therefore, there is no reason to worry!
By Mathieu Rousseau
1) Kostek MA, Pescatello LS, Seip RL, Angelopoulos TJ, Clarkson PM, Gordon PM, Moyna NM, Visich PS, Zoeller RF, Thompson PD, Hoffman EP, Price TB. Subcutaneous fat alterations resulting from an upper-body resistance training program. Med Sci Sports Exerc. Jul;39(7):1177-85, 2007.