NCSF Exercise Physiology Practice Exam

Long-term fatigue during exercise can be attributed to various physiological changes that occur within the body. The correct answer highlights the depletion of electrolyte ions as a significant cause of this fatigue. Electrolytes, such as sodium, potassium, calcium, and magnesium, play critical roles in muscle contraction and nerve function. During prolonged exercise, particularly in conditions where sweating is substantial, the body loses these essential ions, which can lead to muscle cramping, decreased performance, and increased perception of fatigue.

Without adequate electrolyte levels, muscle cells cannot function optimally, leading to impaired muscle contractions and increased fatigue. This depletion also affects hydration status and overall cellular function, which can further compound feelings of tiredness and fatigue during exercise. Therefore, maintaining electrolyte balance is crucial for sustaining endurance and preventing long-term fatigue.

In contrast, while exhaustion of ATP/CP reserves and increased muscle temperature may contribute to fatigue, they are typically more associated with immediate fatigue rather than long-term, chronic fatigue. Increased respiration rate is more linked to the body’s response to increased demand for oxygen during exercise rather than a direct cause of long-term fatigue.