Cortisol’s Role in Training and Performance Optimization

Written by Daniel Taylor

Cortisol is defined as the stress hormone. According to the World Health Organization, stress is defined as a state of worry or mental tension caused by a difficult situation. Stress is a natural human response that prompts us to address challenges and threats in our lives. Everyone experiences stress to some degree. The way we respond to stress, however, makes a big difference to our overall well-being. 

Cortisol’s Role in the Body

Stress and cortisol are synonymous to one another, as in they both work in cohesion with one another. Cortisol has several roles in the body, including regulating your body’s stress response, helping control your body’s use of fats, proteins and carbohydrates, or your metabolism, suppressing inflammation, regulating blood pressure, regulating blood sugar, and helping control your sleep-wake cycle. The body monitors cortisol levels to maintain homeostasis. To regulate the body’s stress response, it releases cortisol after the fight or flight hormones are released, while additionally releasing glucose from the liver to supply energy in times of stress.

Contrary to the belief that cortisol is bad, it is actually not bad. Cortisol becomes bad when it is chronically elevated, meaning when it is high over an extended period of time. Signs of elevated cortisol levels include: trouble sleeping, belly fat, uncontrollable food cravings, digestive problems, depression and anxiety. 

Chronically elevated stress and cortisol levels can affect training goals in a negative way. When training, there are various goals set, and one of those goals may be to increase muscle growth. Elevated cortisol can hinder the growth of muscle by a protein called myostatin. Recovery can be impaired by high stress, slowing the healing process of muscles and causing soreness to become prolonged. With cortisol playing a role in regulating fats, proteins, and carbohydrates, the elevated cortisol levels have an effect on storing fat instead of burning fats, as well as hindering the breakdown of carbohydrates used for energy during workouts.

Strength Training to Regulate Cortisol

People who are highly stressed can be impacted negatively in a physical and mental aspect. One key factor here is physical activity. Having no motivation to continue training can do more harm than good. Physical activity like strength training can positively affect stress management. Strength training can help counter the negative effects of high cortisol levels and positively affect endocrine functions. 

Strength training lowers the acute cortisol response, and it improves chronic cortisol levels. During strength training, testosterone to cortisol ratio increases. Testosterone to cortisol ratio is defined as the ratio between testosterone, the primary male sex hormone and an anabolic steroid, and cortisol. Strength training relieves stress and can be viewed for some as a way to get away from stressors. 

The benefits of strength training on cortisol levels may vary among individuals, and factors such as training intensity, duration, frequency, and overall health influence the body’s responses. Training factors that increase cortisol consist of: neurological stress, psychological stress, high training density, and volume intensity (how hard you push, how close you are to failure you’re getting in each set, and how hard you are pushing yourself each set). The structure of workouts also plays a factor in cortisol regulation. Workouts should be limited to an hour and should include 5 to 6 exercises, with 2 to 3 being big muscle lifts and the rest accessory or single-joint movement exercises. 

As the body adapts to strength training, cortisol levels fluctuate. As time goes on, the body adapts and cortisol levels decrease. This means consistency is key. Consistently training allows you to adapt to exercise and use it as an outlet or to get away from the stressors that occur in life. 

Lastly, combining strength training with other stress management strategies, such as adequate sleep, proper nutrition, and mindfulness practices, can contribute to a comprehensive approach for improving cortisol regulation and overall well-being.


Works Cited

  • ASF Trainer Development Manual, “Lifestyle Factors Lead to an Increase in Cortisol in Highly Stressed Clients.” 
  • Poliquin Editorial Staff – November 12, 2021. “Do Strength Training to Lower Cortisol
  • Cleveland Clinic. “Cortisol”. Lab Tests Online. Cortisol ( Accessed 12/10/2021.
  • MedlinePlus. Cortisol Test ( Accessed 12/10/2021.
  • Thau L, Gandhi J, Sharma S. Physiology, Cortisol ( In: StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing; 2021. Accessed 12/10/2021.