What is a common sign of overtraining in athletes?

A common sign of overtraining in athletes is decreased performance and increased fatigue. This phenomenon occurs when an athlete trains intensively without giving their body adequate time to recover. Overtraining leads to fatigue because the body does not have sufficient energy reserves to perform at its previous levels, and this can manifest in diminished strength, endurance, and overall performance during training or competitions.

Additionally, as the stress on the body exacerbates, athletes may notice chronic fatigue that does not resolve with typical rest, mood changes, and a decline in motivation. These indicators serve as red flags suggesting that the athlete's training regimen may be too intense or insufficiently balanced with recovery.

In contrast, the other options present scenarios that are not indicative of overtraining. Increased energy levels and enhanced recovery times typically reflect a well-structured training plan that includes proper rest and nutrition. Improved cardiovascular fitness would similarly suggest effective training outcomes rather than the dysfunction associated with overtraining.