Which of these is a symptom of over-exertion?

Experiencing chest pains is a significant symptom of over-exertion. When an individual pushes their body beyond its limits, it can lead to physical stress that manifests in various ways, including cardiovascular strain. Chest pain can arise from the heart working too hard, particularly during intense exercise or when one is not adequately conditioned for the activity being performed. This symptom warrants immediate attention, as it may indicate serious health issues such as cardiac distress, which requires prompt evaluation.

In contrast, increased energy levels, enhanced muscle performance, and improved sleep patterns typically reflect positive effects of proper exercise and physical conditioning rather than over-exertion. These outcomes are generally associated with a well-designed fitness regimen that allows for rest, recovery, and appropriate intensity rather than the negative effects seen when someone overextends themselves physically.