Which of the following is an extrinsic risk factor for injury?

The correct choice, fatigue, represents an extrinsic risk factor for injury because it is often associated with external influences such as workout intensity, duration, and environmental conditions. When individuals experience fatigue, their physical performance can decline, leading to compromised movement patterns, decreased coordination, and poor decision-making during physical activities. As a result, this heightened state of fatigue can increase the likelihood of injury, especially in high-risk sports or exercise settings.

The other options, such as type I muscle fibers, play a role in individual physiology, which is considered an intrinsic factor rather than extrinsic. Acclimatization relates to how well an individual adapts to environmental conditions over time and can influence performance but does not directly account for injury risk in the same way that fatigue from external stresses can. Dehydration, while critical to overall physical performance and health, is also somewhat intrinsic, as it relates more to the body’s internal state rather than an external factor that increases injury risk. Thus, fatigue stands out as a clear extrinsic risk factor.