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Stage 2: Sympathetic Overtraining

Many health-care professionals and athletes recognize the start of overtraining in Stage 2. But by this point, as overtraining progresses, imbalances of various systems worsen and become more difficult to remedy easily. Specifically, the sympathetic part of the nervous system becomes even more overactive than in Stage 1, with further worsening of the aerobic system. There is a more significant elevation in the resting heart rate and training heart rate, which further worsens the MAF Test. Many athletes become aware of this if they regularly measure their morning heart rate and train with a heart-rate monitor. Often associated with this elevated heart rate is restlessness and over-excitability.

Stage 2 overtraining is more common in athletes with anaerobic training as a significant part of their workout schedules, including those with too much training volume, those with too much lifestyle stress, and most often those athletes who have a combination of these factors.

Adrenal gland dysfunction and aerobic deficiency more noticeably worsen during sympathetic overtraining. Cortisol output may rise to abnormal levels at various points throughout the day and night. The keen awareness and fine eye-hand coordination required in some sports are adversely affected by these hormone problems. High cortisol levels also have a harmful effect on the physical, chemical, and mental state, much like that produced by exhaustive, prolonged training, including the development of more significant muscle imbalances.

High cortisol also can increase insulin levels, which reduces fat burning and increases fat storage. While aerobic training usually suppresses insulin production during exercise, studies show that maximal training intensities can increase the insulin response significantly. This problem also further raises sympathetic system activity, increases carbohydrate intolerance with more carbohydrate foods converting to fat, and worsens the overtraining syndrome. In addition, elevated cortisol lowers testosterone and DHEA, both important for muscle recovery. Those who frequently wake in the middle of the night and don’t easily fall back asleep typically have high cortisol levels, which is another sign of overtraining.

Fortunately, this hormone imbalance is relatively easy to correct through diet and lifestyle changes, including one’s training and competition schedules. Those who don’t listen to their body and continue overtraining can have worsening signs and symptoms, including reduction in performance and development of chronic injuries. Many athletes remain stuck in this stage of overtraining for months and even years; some “progress” into a more serious and third stage of overtraining.