While athletes of virtually all ages exist, you can train your body more easily at certain stages of your life. Bodybuilders require a high muscle mass and low body-fat percentage to be competitive. The hormone testosterone influences body composition and athletic performance involving explosive power and speed. Testosterone levels vary with age, and estimating the most advantageous times for bodybuilding involves determining when peak levels occur. However, factors other than age can influence successful bodybuilding, such as competitiveness and work ethic.
Testosterone Levels in Adults
Testosterone plays an important role in building muscle mass and lowering adipose tissue content in the human body. It exists in the blood as free testosterone, which is biologically active, and bound testosterone, which serves as a “reserve.” Together, these two values constitute serum testosterone. In men, serum testosterone levels remain about constant throughout adulthood. However, according to a study published in “Human Biology,” free testosterone levels decline steadily after age 20, suggesting that the age when you benefit most from free testosterone levels is around 20.
Testosterone Levels in Children and Adolescents
Serum testosterone levels increase with each Tanner stage of development, with maximum testosterone levels reached upon adulthood. Scientists commonly use Tanner stages, based on the development of sex-specific traits, to describe the progression of puberty. There are five Tanner stages, with stage 1 describing preadolescent development and stage 5 representing development close to that of an adult. At Tanner stage 2, or the onset of puberty, serum testosterone levels begin to increase, and at stage 3, testosterone levels are near half the levels of an adult. At stages 4 and 5, levels are approximately 80 percent of adult values. Testosterone-related advantages in bodybuilding are likely to become more apparent as you approach adulthood.
Resistance Training for Children and Adolescents
While testosterone’s effects may be most evident around age 20, you may be interested in starting bodybuilding at an earlier age. One reason could be to gain an advantage over competitors in your age group. In preadolescents, or those in Tanner stage 1, strength gains are usually due to the body making better use of its nervous system as opposed to increasing the size of its muscles. In adolescents, or those in Tanner stages 2 through 5, as well as in adults, resistance training causes increases in muscle size along with neural adaptations. The earliest age where you can expect to see gains in muscle size from resistance training is at the age of adolescence, which is defined by the World Health Organization as about age 10. The current position of the National Strength and Conditioning Association is that “a properly designed and supervised resistance training program is relatively safe for youth.” However, always consult your physician before starting a new exercise program or for any treatment, diagnostic and medical concerns.
Age of Champion Bodybuilders
Testosterone levels throughout the lifespan can theoretically predict the age most advantageous for bodybuilding, but numerous other influences can contribute to success. Having free time to work out, financial resources to afford a gym membership and maturity and work ethic are some important factors that may be influenced by age. Arnold Schwarzenegger, a well-known bodybuilder, began weightlifting around age 15 and won Mr. Olympia at age 23, becoming the youngest bodybuilder ever to win the competition. He continued to win Mr. Olympia for the next five years. On the other end of the spectrum, Chris Dickerson was the oldest person to win the Mr. Olympia competition at age 43. The average age of Mr. Olympia winners is about 34, showing that there is a wide age range where competitive bodybuilding is possible.
- Current Opinion in Clinical Nutrition and Metabolic Care: Testosterone Action on Skeletal Muscle
- Human Biology: Age Differences in Serum Androgen Levels in Normal Adult Males
- Canadian Journal of Sport Sciences: Resistance Training During Pre- and Early Puberty: Efficacy, Trainability, Mechanisms, and Persistence
- Journal of Strength and Conditioning Research: Youth Resistance Training: Updated Position Statement Paper from the National Strength and Conditioning Association
- Williams Textbook of Endocrinology, 12th edition; Shlomo Melmed et al.
- Journal of Strength and Conditioning Research: Is Testosterone Influencing Explosive Performance?
Ross Patel holds an M.D. from Eastern Virginia Medical School, a master's degree in biology from Towson University and a bachelor's degree in psychology from Washington University in St. Louis. Patel has contributed to the Journal of Ophthalmology and other medical literature.