How Does Exercise Influence Your Cortisol Levels?
As with many fitness questions, the answer to this one is “it depends.” It’s true that exercise has the potential to help balance the stress hormone cortisol. But this benefit hinges on the balance of all life’s stressors, including exercise. Here’s what you need to know to find the balance that’s right for you.
Cortisol 101
Despite its reputation, “cortisol isn’t a bad hormone, but like everything else, the dose makes the poison,” says Monique Class, MS, APRN-BC, a family nurse practitioner and clinical nurse specialist in holistic health at the Center for Functional Medicine.
In the right dose, cortisol serves many functions. It helps regulate the body’s stress response, releases glucose, helps modulate inflammatory processes, and turns down the parasympathetic “rest and digest” system to help deal with a perceived threat. Ideally, once the threat has passed, cortisol levels return to normal.
At least that’s how it’s supposed to work. Chronic stress can increase cortisol levels, creating a disrupted cycle of feeling wired or tired.
Understanding How Intensity and Timing Affect Cortisol
We’ve long been taught that exercise is a great way to unwind, de-stress, and balance cortisol.
The part of the story that often gets left out is that exercise is a stressor too. As such, it causes a cortisol spike.
But that spike isn’t necessarily bad. This postexercise bump is short-lived, lasting about one to two hours after a workout; it can enhance your workout recovery and train your body to handle cortisol more efficiently.
“A regular workout routine can help you adapt to stress through various mechanisms, including improving your blood-sugar regulation, resilience, confidence, and outlook,” says Samantha McKinney, RD, CPT, Life Time national program manager for nutrition and metabolism. This may help your cortisol levels return to normal more quickly after a stressful event.
Exercise, then, can combat stress. But not all exercise is created equal. Again, the right dose is important, and that specifically comes down to exercise intensity and timing.
Intensity: Research has shown that high-intensity workouts create greater immediate cortisol bumps than low-intensity forms. Sounds like a win for high-intensity workouts — but these benefits hold true only when we’re operating in our optimal states.
When we’re working with disrupted cortisol rhythms, it can be helpful to temporarily reduce exercise intensity or duration and pay careful attention to our recovery strategies in between tougher workouts.
Timing: Because intense exercise raises cortisol levels, it can be great for an energy boost in the morning or midafternoon. But a high-intensity workout in the evening, when the cortisol curve is naturally tapering to its lowest levels to facilitate sleep and recovery, can be disruptive to some. For people struggling with insomnia or anxiety, this disruption can be particularly taxing.
Finding Balance
None of this means that you should cut out intense exercise completely or even avoid it at night. Remember: Intense workouts are potentially great for managing stress in the short and long term. It just means you need to be mindful of how and when you go about it, taking note of your current stress levels, sleep patterns, and nutrition.
We can handle only a certain amount of stress without noticeable disruptions in how we feel and function, McKinney explains. That stress can come from anywhere — relationships, work, finances, diet, pain, lack of sleep, or exercise. Some stress is inevitable.
But if you add stressors like physical activity without easing into them, your cup could eventually overflow. When this happens, you may experience a number of symptoms, including chronic fatigue, digestive issues, aches and pains, and a drop in workout performance.
“When your stress cup is overflowing, you may need to temporarily scale back on exercise intensity or duration to keep things balanced,” McKinney says. Great options include low-intensity activities like walking, gentle yoga, or light resistance training.
Observe and track how specific types of exercise make you feel and whether they affect your sleep or energy levels, she adds.
Stay open to modifying your workouts — and whatever you do, don’t skip exercise altogether. A sedentary life is stressful on the body too: Lack of movement can also contribute to cortisol disruption.
Learn how to balance your cortisol levels naturally at “How to Balance Your Cortisol Levels Naturally.”
This article was originally written by health-and-fitness writer Lauren Bedosky for Experience Life, where it appeared as “Cortisol & Exercise: How do your fitness efforts influence this critical hormone?” in the January/February 2024 issue.
