Cortisol and Its Effects on Your Performance

Imagine this; your girlfriend/boyfriend just broke up with you and now you’re absolutely devastated. Or you just got into a huge fight with your roommate about how he’s not paying the rent on time and now you’re absolutely pissed.



What do both of these scenarios have in common? They both are eliciting a strong emotional response (one of sadness and one of anger). Ones that are far different from your standard emotional state.

How Does This Impact My Progress In The Gym Though?

Well, when stressful situations arise in our lives, a hormone which many of you are familiar with called cortisol is released. Many of you most likely know this as the “stress hormone.” But what really makes this hormone so bad?

Inherently, cortisol isn’t either really “good” or “bad”. 1200px-Cortisol2.svgIt is simply released to carry out the body’s catabolic processes. But what does this mean?

Catabolic simply means “to break down”. From a muscle-building perspective, your probably thinking this is the worst possible thing that could happen to you. But hear me out. Your body is constantly breaking (more like tearing) down muscle during training and then recovers during times of proper nutrition and sleep (aka recovery), causing growth (called hypertrophy for us physiology nerds).

Also, cortisol performs a number of other beneficial functions, such as breaking down proteins into amino acids to be used for initiating muscle protein synthesis (the key driver of muscle growth via the amino acid leucine) and breaking down proteins to be converted to glucose (sugar for energy) via a process called gluconeogenesis, when sufficient amounts of carbohydrates are not available to be used for energy.



But What Makes It The “Stress Hormone?”

What gives cortisol a bad name is when it begins to affect the positive adaptations (results) you normally see when your progressing through your exercise regimen. What this hormone has the ability to do is significantly reduce protein synthesis rates, thus halt tissue growth (that hypertrophy we discussed earlier) when produced in excess.

When somebody has excess amounts of this hormone in their body, it can result in:

  • Reduced ability to build lean mass (muscle)
  • Reduced anabolic (“the building up of”) hormone output, such as testosterone, growth hormone, and insulin-like growth factor-1 (IGF-1)
  • Have a negative affect on glucose uptake and utilization throughout the body, therefore, energy is being expended less efficiently in order to fuel your activities, resulting in a more rapid onset of fatigue (that’s no good guys, that’s for sure)

However, this is not to say that cortisol is absolute devil and we should aim to have no cortisol in our bodies at all. Far from it. We need cortisol to perform the bodies necessary basic functionalities that have to do with breakdown which eventually lead to repair and progression. That is when we come back stronger and better. We should aim to keep it at normal levels through easily applied lifestyle changes that can become habits.

What is “Normal”?

That’s a good question. According to the University of Rochester Medical Center [1], serum cortisol levels (blood levels) should be around 10-20mcg (micrograms) per dL (deciliter), which would look like this: 10-20 mcg/dL, given that you take this exam upon waking in a fasted state, around 6-8 a.m preferably. Morning is when your cortisol levels are the highest due to the stress of your body waking you up to start the day, so if you take this test in the afternoon hours, expect a level closer to 3-10 mcg/dL.


However, for those who can’t afford or don’t want to receive a blood test (the preferred method), then a urinalysis (pee test) or salivary (spit test) will also give you an estimate of where your levels are at.

But if you still don’t want to do those tests, that’s fine, money can be tight. There are ways that you can estimate it upon yourself through various symptoms of high cortisol. These include:

  • Fatty deposits around the midsection and upper back and face
  • Slower healing of cuts and bruises
  • Decreased libido
  • Severe fatigue
  • Depression/Anxiety
  • Constant headaches
  • Erectile Dysfunction (men)
  • Irregular or missing menstrual periods (women)

What I just described here are symptoms of a disorder called Cushing Syndrome [2]. This disorder occurs when we are exposed to chronically high cortisol levels over a period months and years. High cortisol is essentially harmless in the short term (couple of days) and insignificant in terms of your health and progress. But if it occurs for a longer period of time and you begin to observe these symptoms or test results that you receive are throwing you a red flag, please seek out a medical professional.



How Do I Control my Cortisol Levels?

Okay, now that we know all about the basics of cortisol, let’s figure out how to control it in order to keep it within healthy ranges.

Methods to reduce cortisol are drastically similar to those of overall stress management.


Everyone knows how important sleep is. Given that everyone is different and requires varying amounts of sleep, 7-9 hours is a good starting point. Over time, things like sleep deprivation and insomnia can wreak havoc on your body and can increase cortisol in the long run. Doing things like using that cool blue light filter on your phone an hour before time (or powering it off completely), putting away all work-related tasks 30-60 minutes before bed, and limiting caffeine intake 6 hours before bedtime can help improve your sleep quality.

The Power of Positive Thinking

Anxiety; many of us gave gone through it (including myself) or know somebody who has. It’s an absolutely terrible feeling and I don’t wish this feeling upon anybody (I will write a specific article for this topic in the future). Whatever the cause may be or whether or not you are taking prescription medication to manage it, learning to take control of your thoughts (as corny as it sounds) is a step in the right direction to manage anxiety and destructive thinking.


Anxiety disorder

Learning to be aware of your negative thoughts when they arise and simply turning them into a positive has helped me tremendously. Acknowledge the raise in heart rate, breathing, and other signs of tension when they arise. That’s it. Don’t attach an emotion to them. Just realize that they are there, it’s happening, and that it will soon go away. Develop an action plan and envision the solution. Visualization is a powerful tool, trust me.


Do I really need to go over this? Those of you reading this most likely know how to eat properly. Eat your protein, get in your micronutrietns with those fruits and veggies, implement those healthy fats, and for God sake, drink a lot of water. Make sure that pee is a bright yellow guys 😉


There isn’t too much to go over in this category, as most supplements marketed for this purpose haven’t been adequately proven in the scientific literature. But there a couple supplements that I have found to help me and have great support behind them in the data.

  • Ashwaganda
    • An herb that was popularized in Ayurvedic medicine
    • Is most notable for reducing anxiety via the reduction of cortisol levels. Lowers cortisol more significantly compared to any other herb out there.
    • In one study, 300 mg (a little less than a standard dose of 400-500 mg) was shown to decrease serum (blood) cortisol levels by 27.9% over 60 days, a very significant drop for a non-drug treatment [3]


  • L-Theanine
    • A non-essential amino acid (meaning the body makes some of it in the body without obtaining it from diet or supplementation)
    • Appears to promote relaxation without sedation (sleepiness)
    • One study found that an increase in alpha brain wave function (electroencephalogram, which is a significant marker of mental relaxation and concentration in the frontal and occipital lobes of the brain)  in healthy adults was significant in those with high baseline anxiety after ingesting 200 mg L-theanine (higher end of the standard dose) in 30 minutes [4].
I’m not sponsored in any way by NOW Sports, but I am a firm believer in the quality and efficacy of their products

Final Thoughts

Cortisol has many other catabolic functions throughout the body that expand beyond the scope of muscle building and fat loss. This just scratches the surface of it in order to inform you of the basics so that you can make the right decisions for your health.

If you have any questions about any aspect of this topic, please don’t hesitate to reach out via the comments or my email!



1. Cortisol (Blood). (n.d.). Retrieved from

2. Nieman, L. K. (2015). Cushings syndrome: Update on signs, symptoms and biochemical screening. European Journal of Endocrinology, 173(4). doi:10.1530/eje-15-0464

3. Chandrasekhar, K., Kapoor, J., & Anishetty, S. (2012). A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of Ashwagandha root in reducing stress and anxiety in adults. Indian Journal of Psychological Medicine, 34(3), 255. doi:10.4103/0253-7176.106022

4. Song, C., Jung, J., Oh, J., & Kim, K. (2003). Effects of Theanine on the Release of Brain Alpha Wave in Adult Males. Korean Journal of Nutrition, 36(9), 918-923.