Physics and physiology enable the world’s most flexible athletes

My second grader has recently become concerned about doing the splits. A bit of time in a basic gymnastics class has opened her eyes to a whole slew of ways the body can flex and bend beyond the double-jointed thumb she likes to yank backward from time to time. As a beginner, she’s not yet able to contort her body as much as she’d like, but time and chromosomes are on her side, at least for a while.

Advantages of adolescence

It’s no accident that the world’s top female gymnasts are young. For growing athletes’ safety, there’s actually a rule that competitors in the Olympics are at least 16 years old, but obviously training starts well before that age. Youthful exuberance is only a small part of why these young women are able to bend and leap like no one else, although there is some truth to the notion that age makes us less flexible. Younger athletes literally have not had time to wear out joints that naturally lose flexibility with age, often in the form of bone spurs or arthritis. The other advantages of these young gymnasts are more tied to to hormones and physics

Women under age 30 produce more of a hormone called relaxin. This is produced so that the woman’s body can stretch and accommodate the changes demanded by carrying a baby when she’s pregnant. Joints are made more supple by relaxin, and while it spikes during a pregnancy to facilitate childbirth through our bipedal hips, even prepubescent women gain some extra flexibility to a degree.

Low-ballast bodies

Many young gymnasts are also notably small in stature, which isn’t just a byproduct of their age. Being small provides advantages for tumbling and jumping, as the athlete will have a lower center of gravity, while also weighing relatively little. Trained muscles therefore have an easier time launching a small, nearly fatless body off the ground, all of which counts when you’re aiming to complete that third twist or second consecutive flip. It may also be a reason that my daughter, who is on the tall side, may want to leverage her natural body type towards swimming more than gymnastics, at least as far as competition goes.

Source: Why Are Gymnasts So Flexible? by Laura Geggel, Live Science