Cortisol is a steroid hormone produced by the adrenal glands, which sit atop the kidneys. Cortisol is similar to many drugs, such as hydrocortisone and prednisone. Often labeled as a ‘stress’ hormone, cortisol also helps regulate blood sugar and electrolytes, aids in fat, protein and carbohydrate metabolism and perhaps most importantly, controls inflammation in our bodies.
Cortisol is produced at higher levels in the early morning hours, and then slowly descends throughout the day and is low through the night. We can’t live without this hormone, and too much of it can ruin our health.
Elevated Cortisol Effects
However, when we become stressed, either mental-emotionally or physically, our bodies churn out much more cortisol – hence being dubbed a ‘stress’ hormone. Cortisol is our body’s natural anti-inflammatory. One of the reasons we produce it in times of stress is because nature anticipates injury when we are stressed. While we don’t have to hunt and fight off wild beasts these days, our bodies still respond in anticipation of stress-induced bodily injury. (Starvation is another stress, and cortisol elevates to help mobilize stored fats and sugar from the liver when food is scarce.)
Too much stress, such as the amounts we make when we are chronically stressed – can damage our health and limit our recovery. When we train, we are stressing our bodies. Physical training-induced stress followed by recovery is an important training principle. However, with too much training and not enough recovery comes chronically elevated cortisol, and diminishing returns on our performance gains and overall health.
In chronic stress states, elevated cortisol can lead to inexplicable weight gain (especially around the midsection) insomnia (most often evidenced by waking at 3 or 4 a.m.), tissue breakdown in the form of ‘itis’ – tendonitis, or uncontrolled tissue inflammation, suppressed immunity and lastly, interference with other hormones, namely thyroid hormone. This is part of why in chronic stress states we can feel so rotten – the actions of our other hormones are blocked by cortisol.
Cortisol and Overtraining
An athlete who trains excessively, without proper rest and recovery, will have chronically elevated cortisol levels and after time will start to experience the above problems. And if they don’t become symptomatic, their recovery will be poor and this reflects on future performance. This is part of the ‘overtraining syndrome’ and is why an athlete can train and train and wake up on race day feeling flat and have a lackluster performance, despite doing loads of training.
We’ve established that too much cortisol is counterproductive for training. But how can you get it under control. Here’s a list of the most important ways to get your cortisol rhythm back to normal – all of which are central tenets of recovery!
1. Sleep from 10pm-6am (or as close to that as you can)
The golden hours of sleep are from 10pm to 6am. Those same 8 hours from say, 1am to 9am are of less quality, and won’t allow for your body to establish a normal cortisol rhythm.
Skipping meals, not eating after a big workout and generally getting too few calories sends a stress message to your hypothalamus and can result in cortisol secretion. Keeping blood sugar at normal levels by consuming a mixture of protein, fat and carbohydrate immediately after a workout will stimulate proper recovery conditions. A small amount of protein at bedtime (15 grams or so – a hardboiled egg and handful of nuts) will keep blood sugars stable during sleep, and cortisol down.
As in, deal with your stressors. Stress is a part of life, some of which we can’t control. But do try to engage your stressors in a productive way. Even taking small steps at stress reduction can have impressive effects on lowering cortisol levels.
Yes, the 4-letter word that no athlete wants to hear. If we take real rest and recovery days, rather than further stressing our bodies with more training (raising cortisol), the body will stop churning out cortisol, allowing true recovery to take place. Less is more!
Measuring Cortisol Levels
If you’re curious about your cortisol levels, you can measure them at home using a saliva test. A saliva test gives a much better indication of ‘functional’ cortisol levels, or how much your body is really producing. A standard blood test doesn’t measure cortisol in small enough units to tell us if your levels are off.
Getting cortisol levels under control is important if you want to have better results from your training. Cortisol levels left unchecked are counterproductive for athletes and the benefits we expect from training.