In order to enhance development of muscle strength and size, you need to be engaged in resistance training. This is mandatory. In order to get the most bang for your resistance training buck, you need to have adequate testosterone levels. Testosterone is a steroid hormone secreted from specialized cells in the testes in men and in smaller amounts from the ovaries in women. Testosterone has potent anabolic (muscle building) effects on muscle tissue.
What can elevated testosterone levels do?
Three absolute requirements to build muscle
One way to naturally manipulate testosterone levels is through diet. Dietary nutrients and hormones (like testosterone) work together to regulate repair of skeletal muscle proteins that are broken down during training. Manipulation of these variables to favor anabolism (building up) over catabolism (breaking down) during recovery enhances the development of muscle strength and size. Resistance training provides the stimulus for increasing muscle size and strength but without the right building blocks supplied from diet and the right hormonal environment, optimal gains in size and strength will not be achieved.
In summary, cross-sectional and diet intervention studies indicate that low-fat diets (20-30% of calories) are associated with lower testosterone levels compared to diets higher in fat (about 40% of calories). The type of protein is also important. Reducing vegetable protein in favor of animal protein can increase the resting testosterone levels and complement, not blunt, the normal exercise-induced increase in testosterone.Testosterone killer - calorie restriction
Other studies have also shown decreases in testosterone levels in wrestlers while consuming a low caloric energy diet. Guezennec et al (1994) measured testosterone in soldiers consuming low (1800 kcal/day), moderate (3200 kcal/day), or high (4200 kcal/day) calorie diets with similar ratios of carbohydrate, protein, and fat. The diets were consumed during 5 days of prolonged exercise and sleep deprivation (4 hrs/day). After 5 days, testosterone had decreased by ~50% on the low calorie diet and only about ~20% on the moderate and high calorie diets. These findings indicate that exhaustive exercise can decrease testosterone levels and that inadequate energy can speed up the decrease in testosterone.
Collectively the studies that have examined the effects of energy intake on testosterone indicate that large reductions in calories and body weight can reduce testosterone levels. This is especially true if a large reduction in calories is combined with prolonged and exhaustive physical activity. If weight loss is a goal, a much better approach would be to reduce calories slightly (about 300-500 kcal/day) and incorporate heavy resistance training into your exercise program. This should eliminate the decrease in testosterone that typically occurs when calories are reduced.The bottom line