Weight loss is achieved by creating a negative energy balance: expending more calories than the amount consumed. However, all weight loss is not created equal. Weight loss comes from a combination of both fat mass and fat-free mass; the loss of fat-free mass (FFM) results in a decreased resting metabolic rate (RMR).
This decrease in RMR can slow the overall weight loss process and decrease the likelihood that the weight that is lost can be maintained once the dieting period is over. The good news is that performing resistance training during periods of negative energy balance can mitigate the loss of FFM. This article will provide examples of how to do this.
Jeffrey Alexander, MS
The Role of Resistance Exercise in Weight Loss
Strength and Conditioning Journal, February 2002
Volume 24, Number 1, pages 65-69