In the Olympics, the minimum age to compete in gymnastics is 16, but if you didn’t know that you would guess that gymnasts like USA’s Shawn Johnson or China’s Deng Linlin were 13 or 14. Most people do, which is why many gymnasts are under suspicion of faking their age. After all, swimmers or soccer players don’t look so young, so why only gymnasts? Fear not, there is a perfectly simple physiological explanation behind the delayed growth and puberty of gymnasts, especially in female gymnasts.
The common trait among gymnasts is that they’re short. While there is a biological reason for stunted growth there’s also an athletic reason: being short gives you an advantage in gymnastics due to the physics involved in the motions. So taller gymnasts usually aren’t able to compete with shorter gymnasts and thus don’t train as long or rigorously. But there are physiologically reasons why gymnasts’ puberty is often delayed:
1) Length of training
Gymnasts often begin training by the time they’re 4 or 5 years old. They’re usually about 7 or 8 year old when coaches and trainers begin to recognize talent in them, and that’s when the prodigies are picked out. They begin to work hard and diligent sometimes 10 years before they’ll compete in an international competition. Whereas other athletes, such as Michael Phelps or Lance Armstrong, begin the sport when they’re 11 or 12, while they’re already in the process of puberty.
These gymnasts start at a much younger age and train with the same vigor that other athletes do when they’re the best in their sport. Their training continues through when normal girls begin puberty, around age 11, and beyond. Because their bodies are much more physically fit from all the years of training, it imbalances the hormones and delays the process of adulthood.
Gymnasts are unbelievably fit when they’re adults, so imagine that kind of fitness in a child. Specifically, they have low body fat. And this doesn’t just pertain to gymnasts, almost all Olympic athletes have low body fat, sometimes in the single digits. And gymnasts have had low body fat since they were 5. Because the stores of fat are so low the body thinks, “I don’t have a lot of fat supply. Maybe it’s best not to grow up right now and wait until I have a little more fat.”
The low levels of fat cause two big reactions in the body that delay puberty:
1) Decreasing levels of gonadotrophin. If you didn’t already infer from the name, gonadotrophin is responsible for the creation of sex hormones. Decreased levels of this delay the normal symptoms of female puberty, like increased breast tissue, darker arm, leg and pubic hair, and menstruation. Most gymnasts eventually undergo puberty by the time they’re 13 or 14, sometimes even 15. Unfortunately, because their puberty is delayed and not allowed to develop correctly, these gymnasts often experience hormonal problems, and sometimes infertility, in the future.
2) Lower levels of insulin-like growth factor (IGF-1). Less fat and sugar means less glucose, means less insulin, means no growth. This is the reason gymnasts don’t often grow above 5’3″. The big growth spurt during puberty is caused by IGF-1. It allows long bones, such as the femur and humorous, and soft muscle tissues to grow into adulthood. Because gymnasts train so rigorously, their muscles are already fit and strong so they really don’t have much need to grow anymore. But the bones are the structures that suffer most. There haven’t been many studies because there aren’t many elderly gymnasts, but I wouldn’t be surprised if in 20 or 30 years they discover that gymnasts are more likely to get osteoporosis than regular women.
So what can be done? Honestly, not a lot. Female gymnasts can try oral contraceptives to help boost production of sex hormones, but realistically, they probably won’t want to. Delaying puberty helps these girls keep their bodies short and limber, and that’s better for them when it comes to competition.
If you’re thinking of putting your child into gymnastics and it turns out your child is an Olympic prodigy, consider this parents: 1) Does your child like the sport?? and 2) Is it worth the consequences they may face later in life due to a delayed puberty?