The risk of injury in senior athletes depends on a variety of factors, including body type, genetic makeup and the sport being played. But an oft-overlooked factor is the kind of athlete an individual is. There is no formal classification, but there are roughly three categories, each with its own risk potential:

•Never stopped: These athletes have continued to play since college or high school. With almost religious fervor, they have maintained a level of fitness others only dream of. They have also continued to put significant stress on their bodies, increasing the chance of injury because of repetitive motion or overuse.

•New to the game: Because they took up tennis in their 20s, skiing in their 30s or golf in their 40s, these athletes may be freer of injury than longtime athletes, but they are also less conditioned and less skilled. They often try to do too much before they’ve perfected a skill or do not dedicate enough time to conditioning.

•Weekend warrior: They have no time to train, but in their minds these athletes never stopped. Back on the court, muscle memory and pride kick in, and they play as though they’d never cut back. This is probably the highest-risk category.

Rebecca Leet