What key factor should you monitor to avoid overtraining during endurance training?

Monitoring resting heart rate is essential in preventing overtraining during endurance training because it serves as an indicator of the body's recovery status. Typically, when a person is well-rested, their resting heart rate will remain stable or show a positive trend. However, if a person becomes fatigued or overtrained, their resting heart rate may elevate, reflecting the body’s increased stress response and decreased recovery capabilities.

This measurement can help detect potential overtraining before more severe symptoms manifest. An unusually high resting heart rate over several days can signal that the body is not recovering adequately, prompting a need for adjustments in training intensity, volume, or rest periods to prevent potential negative consequences.

While daily weight changes, weekly distance covered, and muscle soreness levels can provide useful insights into an athlete's training and physical status, they do not specifically and consistently indicate overtraining as effectively as resting heart rate does. Daily weight changes can fluctuate for various reasons, rather than solely reflecting training load, and muscle soreness can be influenced by numerous factors unrelated to overall training capacity. Similarly, weekly distance may indicate training progress but will not directly inform how well a body is recovering from that training.