Unless you do something about it, testosterone levels begin to fall once you reach your mid-30s. Testosterone is a muscle-building hormone that's connected to your virility, but if you're not giving your body any reason to make more muscle or maintain what you have, there's no stimulus to keep your testosterone production from falling. Why does this matter? Well, boosting your testosterone levels will help keep your sex life healthy.

While there are blood tests to tell if you're running low on testosterone, a simple indication can be a lack of amorous feelings in the morning. If that's you, you may be running low on the stuff.

Testosterone 101

This hormone is produced from cholesterol, which your body naturally produces and you can get from animal foods. To optimize production, you need a reasonable amount of dietary fat and all the essential fatty acids your body can?t produce. A good diet will have roughly 20 percent of your calories coming from good sources of fats?including salmon, nuts, and seeds rich in omega-3 and omega-6 fatty acids.

Crash diets will also put a stop to your body's testosterone production. That's because drastic calorie reductions trick your body into believing that it's starving. Since reproduction is testosterone's primary job, and it's a waste of time and energy to reproduce when you're starving, testosterone levels fall. If you need to lose weight, stick to a balanced diet combined with an exercise program. A good guideline is cutting enough calories so that you lose 1-2 pounds a week, and no more than that.

Multi-joint weight lifting ramps up the testosterone factory. Studies show that lifts such as squats, lunges, and plyometrics (jumping drills) increase testosterone production more than isolated-muscle movements like biceps curls or leg extensions.

Insufficient rest and lack of sleep can cause testosterone levels to plummet because your body can't keep up with the stress you?re placing on it.

Adapted from 5 Essentials for a Winning Life.