Which factor is considered a biological predisposition for fractures?

Age is considered a biological predisposition for fractures due to the natural changes that occur in bone density and strength as individuals grow older. As people age, bones typically lose mineral content, leading to osteoporosis and making them more susceptible to fractures even from minor falls or impacts. The decrease in muscle mass and strength that can accompany aging also contributes to a higher risk of falls and subsequently, fractures.

In contrast, while factors like the angle and duration of force applied and participation in extreme sports can increase the risk of fractures, these are mostly related to environmental and lifestyle factors rather than biological predisposition.