What are the two common physiological markers of overtraining?

The correct choice identifies the two common physiological markers of overtraining as sympathetic and parasympathetic overtraining. Overtraining syndrome can manifest as an imbalance in the autonomic nervous system, which consists of these two branches.

Sympathetic overtraining is characterized by elevated levels of stress hormones such as cortisol and adrenaline, leading to increased heart rate, high blood pressure, and other stress-related responses. This state can result from excessive training without adequate recovery.

On the other hand, parasympathetic overtraining reflects a decreased performance in physical and mental tasks, often associated with fatigue, reduced heart rate variability, and slower recovery times. The relationship between these two branches of the autonomic nervous system is crucial in understanding how overtraining can impact an athlete's overall performance and health.

The other options do not fully capture the specific physiological markers that are widely recognized in scientific literature as indicators of overtraining. For example, while cardiovascular strain and muscular fatigue can occur due to excessive training, they don't specifically diagnose overtraining. Increased strength and decreased endurance may happen due to various training biases but do not specifically indicate overtraining by themselves. Lastly, dehydration and electrolyte imbalance are important for overall performance but do not represent the primary physiological markers of overtraining.