Why do swimmers reach their peak performance at a relatively young age compared with track and field athletes? Particularly female swimmers seem to produce their best results in their late teens to early twenties. This seems to be true for both sprint and longer distances.
My hypothesis: Swimmers peak at a younger age than track and field runners because of metrics such as explosive and dynamic strength, reaction time, and speed of limb movement. Ages of winners in strength and speed events have historically peaked earlier than endurance events (see below).
The first table shows what psychomotor and physical factors are utilized during a given sport/event. Swimming and short distance events utilize explosive and dynamic strength, reaction time, and speed of limb movement, unlike medium and long distance running events. In comparison (the second table shows the mean ages of gold medal winners in given sports/events between 1896-1980), the mean age of gold medal winners in medium and long distance running events have generally and consistently been higher than gold medal winners in swimming and short distance events.
Keep in mind, water is 773 times denser and 55 times more viscous than air(1). One could argue that more energy is spent in swimming than running due to resistance. An article states the following:
“What makes swimming different? Simply put, running is a natural
activity, while swimming is a ‘natural struggle.'”
To put the two sports in perspective, in world record time, a 1500m freestyle swimming event (men: ~ 14:30 min.) takes 10+ minutes more to complete than a 1500m run (men: ~ 3:30 min).
Characteristics of strength and speed events include reaction time, speed of limb movement, flexibility, explosive strength, and gross body coordination. Characteristics of endurance events include control precision, rate control, arm-hand steadiness, aiming, and stamina.
Human strength peaks at age 25(2). Human reaction time also peaks in the 20s(3). From a neural standpoint: As we age, humans lose brain connections(4), which contribute to slower reaction times.
I used this study to answer your question. For the purposes of this question, I did not include outliers or exceptions to said research.