7 min read Testosterone levels in men naturally decline with age. After age 40, it may drop about 1 to 3 percent a year. Maintaining a healthy weight is important in maintaining testosterone levels. Hormones in fat cells can inhibit testosterone production by increasing estrogen. Resistance training temporarily boosts testosterone levels, especially if lifting heavier weights and performing compound movements. The added stress to muscles signals to the brain to produce more testosterone. There is a lack of evidence that supplements, including Tongkat Ali, will meaningfully raise testosterone levels. Welcome to Testosterone HQ— Men's Health 's guide to the exciting, complicated, and revolutionary world of testosterone. For everything you need to know about T, click here . TESTOSTERONE IS RESPONSIBLE for so many important functions, from building muscle to getting and keeping erections. Then there’s the health benefits you may not see: stronger bones and improved red blood cell production.…