How does altitude affect athletic performance?

Altitude significantly impacts athletic performance primarily due to changes in oxygen availability. At higher elevations, the atmospheric pressure decreases, leading to a reduction in the partial pressure of oxygen. This diminished oxygen availability can impair oxygen delivery to the muscles during physical activity. As a result, athletes often experience reduced aerobic capacity and endurance when competing or training at high altitudes compared to sea level.

This physiological response is known as altitude sickness, which can manifest as fatigue, decreased stamina, and impaired exercise performance. Consequently, many athletes who train at high altitudes must allow for an acclimatization period to adapt physiologically to the lower oxygen levels before athletic performance can be optimized.

In contrast, the other options do not accurately reflect the relationships between altitude and performance. While some athletes may benefit from training in altitude to enhance their performance at lower elevations due to adaptations over time, the immediate effect of altitude itself is a challenge to oxygen delivery, making the choice that highlights this impairment the correct response.