Of all the negative issues that can occur when dieting, few can compare in magnitude to muscle loss. Not only will losing muscle have significantly detrimental effects on your appearance, but losing lean body mass can impair your metabolism and making it easier to regain lost weight once the diet has commenced, and can have significantly negative effects on your overall health. In fact, according to R Wolfe, preserving lean body mass may be one of the most significant things you can do to prevent disease and prolong your lifespan as you age (1). In order to preserve muscle when dieting, the following steps should be employed:

#1: Eat Large Amounts of Protein

The first thing you should do when going on a diet is increase your protein intake. For most people, the International Society of Sports Nutrition recommends consuming roughly 1 gram of protein per pound of bodyweight (2). While on a diet, however, this should be significantly higher; ideally somewhere in the 1.5-2.0 g per pound of bodyweight range. The reason for this is that while on a diet, the body often is forced to turn to amino acids for fuel. By increasing your protein intake, your body can use dietary proteins to supply the amino acids and won’t have to breakdown muscles to get this fuel.

In fact, Mettler et al has shown that increasing your protein intake while dieting can greatly decrease the amount of lean body mass lost while dieting (3). For those who plan to significantly restrict their caloric intake, consuming ample protein is mandatory.

#2: Lift Weights

Even more important than increasing your protein intake is to lift weights. Muscle is very metabolically active, and when in a caloric deficit, your body prefers to lose muscle rather than fat. Unless you give it a reason to maintain muscle, most of the weight you lose when dieting will be lean body mass. According to a research study by A Geliebter et al, while subjects who lifted weights for 1 hour per day lost weight the same amount of weight as those who performed aerobics for 1 hour every day, those who lifted weights preserved significantly more muscle and lost more fat, while the other group lost mainly lean body mass (4).

In fact, research by Glover et al, resistance training is the number one way to prevent muscle loss while dieting, even more than dietary measures (5). For those who plan on restricting calories significantly, resistance training should be absolutely mandatory.

References

1 Wolfe RR. The underappreciated role of muscle in health and disease. American Journal of Clinical Nutrition. 2006; 84(3): 475.

2 Campbell B, et al. International society of sports nutrition position stand: protein and exercise. J Int Soc Sports Nutr. 2007; 4: 8.

3 Mettler S, Mitchell N, Tipton KD. Increased protein intake reduces lean body mass loss during weight loss in athletes. Med Sci Sports Exerc. 2010 Feb; 42(2): 326-37.

4 Geliebter, A. Maher, MM. Gerace, L. Gutin, B. Heymsfield., SB. Hashim, SA. Effects of strength or aerobic training on body composition, resting metabolic rate, and peak oxygen consumption in obese dieting subjects. American Journal of Clinical Nutrition. 1997; 66: 557-563.

5 Glover El, Phillips SM. Resistance exercise and appropriate nutrition to counteract muscle wasting and promote muscle hypertrophy. Curr Opin Clin Nutr Metab Care. 2010 Sep.