Physical Overtraining

Neuro-hormonal Model

If overtraining occurs, there is no sufficient recovery time between workouts; progress is hampered. An acute increase of catecholamines (epinephrine and norepinephrine) occurs during exercise. During overtraining, prolonged epinephrine and norepinephrine levels can decrease testosterone and increase cortisol thereby stunting or inhibiting adequate adaptation.


Overtraining is often thought of as absolute, or a black and white phenomenon. Overtraining should be viewed as a continuum, or in shades of gray. An exerciser or athlete may be slightly overtrained and make progress, just not as much as if they were not overtrained.

Specific General
  • muscle worked to exhaustion
  • traumatic orthopedic injury
  • body exhausted after bout
  • glycogen depleted
  • sympathetic response elevated
  • cortisol levels increase
  • muscle becomes weaker over time
  • orthopedic overuse injury
  • body becomes weaker over time
  • glycogen depleted over time
  • Parasympathetic response
  • Increased cortisol levels

Signs of Overtraining

  • Increased resting heart rate
  • Increased resting blood pressure
  • Decreased maximal power output
  • Decreased sports performance
  • Decreased maximal blood lactate concentrations
  • Slower recovery after exercise
  • Weight loss
  • Decreased appetite
  • Decreased desire to exercise
  • Increased irritability and depression
  • Increased incidence of injury
  • Increased incidence of infection
  • Decreased resting heart rate
  • Faster return of heart rate to resting value after exercise
  • Decreased sports performance
  • Decreased blood lactate concentrations during submaximal and maximal exercise
  • Unemotional behavior

Stone MH, Keith RE, Kearney JT, Fleck SJ, Wilson GD and Triplett NT. Overtraining: A Review of the Signs, Symptoms and Possible Causes. The Journal of Applied Sports Science Research 5:35-50, 1991.

Heart Rate Monitoring

Overtraining in Athletes

Heart rate can be monitored to assess the athletes’ reaction to the previous days training program. Pulse should be taken upon awakening before getting out of bed. A baseline can be established by recording morning heart rate for several days. Base heart rate drops progressively as the athlete adapts to training. However, if morning heart rate is significantly elevated it could either indicate that the previous day’s training was not well tolerated or that the athlete did not adhere to an ideal athletic lifestyle. For example, the athlete may have not been getting sufficient sleep or maybe fatigue from illness. The coach and athlete should be aware of the implications of elevated base heartbeat and should be able to change the training plan accordingly. if overtraining is suspected, training volume or intensity should be decreased. If morning heart rate is greater than 5% above baseline, reduce training volume or intensity for that day. If morning heart rate is greater than 10% above baseline, reduce training volume or intensity until base heart rate decreases to baseline levels. (Bompa & Carrera 2015)

However, Hausswirth & Mujika (2013) warn that heart rate variability does not provide consistant results. A performance decrese of greater than 10% on two tests seperated by 4 hours can indicate overtraining if other signs and symptoms are present.

Bompa T, Carrera M (2015) Conditioning Young Athletes. Human Kinetics.

Hausswirth C, Mujika I (2013). Recovery for Performance in Sport, Human Kinetics, 100-108.

Prevalence in Athletes

10-20% of athletes who train intensely experience overtraining which results in chronic decreases in performance and impaired ability to train.

Raglin J, Barzdukas (1999). Overtraining in athletes: The challenge of prevention. ACSM. Health Fitness J. 3:27-31.

Overreaching & Tapering

Overreaching is characterized by a sharp increase in training volume. Overreaching is thought to be an early stage of overtraining which can result in increased fatigue and performance decrements. However, an increase in performance above baseline can occur, if an overreaching phase of approximately 1 week is followed by an immediate return to normal training. A taper following normal training can result in additional performance increases.

Stone MH, Pierce KC, Sands WA, Stone ME (2006). Weightlifting: Program Design. Strength and Conditioning Journal, 28 (2), 10-17.

Hormonal Fluctuation Model

Barbell Clean

A higher testosterone to cortisol ratio correlates with increases of maximal strength performance

Hakkinen KA, Pskarinen A, Alen M, Kau hanen H, Komi PV (1987). Relationships between training volume, physical performance capacity, and serum hormone concentrations during prolonged training in elite weight lifters. International Journal of Sports Medicine, 8 (suppli): 61-65.

  • 30% drop in Testosterone/Cortisol Ratio is proposed to be too extreme for effective recovery of performance after training
  • Changes of less that 10% in Testosterone/Cortisol Ratio is proposed to be too small and lead to lesser performance improvements
  • Performance should be optimal if period of training can be adjusted to lower T/C ratio between 10-30% that is followed by a period of recovery.

Glutamine/Glutamate Ratio and Overtraining

  • GN/GT ratio >5.88 = Normal
  • GN/GT ratio >3.58 <5.88 = Adaptation
  • GN/GT ratio <3.58 for <2 weeks = Over Reaching
  • GN/GT ratio <3.58 for >2 weeks = Over Training

Lon Kilgore, Ph.D., Midwestern State University, Exercise Science Laboratories and USA Weightlifting Regional Development Center, Wichita Falls, Texas.


Some authorities mistakenly misattribute injury to a specific movement when, if fact, other factors such as overtraining are to blame. See:


Extreme muscular exertion may cause Rhabdomyolysis, a breakdown of muscle fibers resulting in a release of their content into the circulation. Some of these contents, such as myoglobin may cause kidney damage. Symptoms include abnormal urine color (dark, red, or cola color), muscle pain, general weakness, vomiting, and confusion, depending on the severity.

Some people are more susceptible to rhabdomyolysis due to a hereditary muscle condition. Inexperienced exercisers are particularly susceptible such as military recruits in basic training, marathon or triathlon participants, or dehydrated or heat-stressed exercisers. However, several experienced athletes have also been known to develop Rhabdomyolysis. In one case, personal trainers encouraged athletes to overexert themselves to the point where they required assistance in walking from one exercise machine to another.

Medical attention should be sought if Rhabdomyolysis is suspected. Diagnosis is made with blood tests and urinalysis. Treatment includes intravenous fluids but may include dialysis in more severe cases.

Huerta-Alardín AL, Varon J, Marik PE (2005). Bench-to-bedside review: rhabdomyolysis – an overview for clinicians. Critical Care, 9(2): 158–69.

Zatsiorsky VM, Kraemer WJ (1995). Science and Practice of Strength Training. 2nd Ed, 85.

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