Testosterone is the male hormone that supports muscle growth. Levels of it vary from person to person, as do metabolic rates. Just as some individuals are gifted with a faster metabolic rate, some bodybuilders naturally have higher amounts of testosterone than others.
To gain mass, it's your job to protect what you've got--to keep your testosterone levels from falling in order to sustain an anabolic environment that will allow you to pack on the beef.
Keep in mind that you have to stimulate your muscles fully for growth, but then have to allow them the opportunity to recover, because that's when growth occurs. Also, address your supplement needs with vitamin C and PS. Follow this advice for maintaining anabolic hormone levels and you'll grow like a weed.
 DON'T SKIMP ON MEAT
Research shows that, unlike a diet rich in meat, a vegetarian diet can cause a drop in testosterone and that a diet higher in fat promotes higher testosterone levels than does a diet lower in fat. Meat contains cholesterol, a precursor to many hormones, including testosterone. Red meat is high in zinc, which is a must-have mineral for supporting testosterone. Include steak, lean ground beef or roast beef in two of your five or six daily meals to sustain testosterone levels.
 PACK IN REFINED CARBS AFTER TRAINING
You should be aware that your postworkout meal ought to be abundant in simple carbs--about .5 to .6 grams (g) per pound of bodyweight. This will help spike insulin, switching your metabolism into a muscle-building state. Here's the other reason for consuming sugar after training: A postworkout high-insulin environment suppresses cortisol, the muscle-destroying hormone that can push your metabolism into a catabolic or muscle-wasting state. Elevated cortisol not only tears down muscle tissue, but it also decreases testosterone. Adequate postworkout carb intake can help prevent cortisol levels from driving down testosterone.
 CONSUME WHEY PROTEIN PLUS GLUTAMINE BEFORE TRAINING
Whey is an easy-to-digest protein that is high in branched-chain amino acids (BCAAs). One study showed that consuming BCAAs before an endurance activity helped sustain testosterone. In practical terms, 20 g of whey would yield roughly 7 g of BCAAs. Throw in 5 g of glutamine to help moderate cortisol and maintain testosterone. Combine the whey/glutamine with a small amount of slow-burning carbs, such as oatmeal or Cream of Rye cereal, or mix it with water and complement it with a slow-burning carb source, such as yams, rye bread or red potatoes. Consume this meal about 40 minutes before training.
 PACK IN PS
Physphatidylserine (PS) is a supplement derived mainly from soybeans. PS and other phospholipids are found in cell membranes. PS has been shown to reduce cortisol elevation during exercise, promote homeostasis within the body's cells and support the proteins that manage membrane function. Take 800 milligrams (mg) every day, if you can afford it, or at least before workouts on hard-training days, to help control your cortisol levels. Again, keeping cortisol down helps maintain higher testosterone levels.
 BOOST VITAMIN C INTAKE
Orange juice is a decent source of simple carbohydrates for your posttraining meal, and it's also a prime source of vitamin C. Consider boosting your intake even more by supplementing with vitamin C. Research has shown that supplementary C can help lower cortisol levels in weightlifters. You know the mantra: Excessive cortisol equals compromised testosterone levels. Take at least 500 mg of vitamin C in the morning with your first meal, and another 500 mg in the late afternoon with your third or fourth meal.
 DON 'T OVERTRAIN
How do you know if you're overtraining? If you follow a high-calorie diet that includes at least a gram of protein per pound of bodyweight per day and you still fail to grow, chances are you're overtraining. Training too frequently or performing too many sets in each training session will cause cortisol to run rampant. That, in turn, lowers testosterone, keeping you from packing on the mass you're trying to build. It may be hard to accept, but you need to schedule more rest days and back off on the total number of sets performed for each bodypart. If you do this, you'll begin to notice gains in mass and improved recovery as a result of lower cortisol! increased testosterone levels.
 SKIP THE AEROBICS
Aerobic exercise reduces testosterone. When it comes to reducing bodyfat, aerobics can be an important part of the equation. When it comes to adding muscle mass, though, aerobics may work against you. Even if you're performing only moderate amounts of it, aerobics could potentially lead to fatique or overtraining. Both of these conditions can interfere with muscle growth by boosting cortisol, which in turn suppresses testosterone levels.