CORTISOL 101

WHY TOO MUCH HIGH-INTENSITY EXERCISE ISN’T GOOD FOR YOU

By Chaya Tziry Retter, RDN, BS, CPT

Chaya Tziry Retter is a Monsey-based Registered Dietitian, ACE-Certified Personal Trainer, and group fitness instructor. She is passionate about helping others lead healthier lives in a way that suits their needs. She can be reached at 845-540-4487.

If you’ve been learning about health and wellbeing, you’ve certainly heard the word “cortisol.” Not sure exactly what it means or how it impacts the body? Let’s explore.

Cortisol, the hormone responsible for regulating changes in the body that happen in response to anxiety and tension, plays a role in managing the body’s fight-or-flight response. This “crisis management department” keeps our eyes wide open and our attention as focused as possible to save us from danger or harm. In a moment of crisis, other systems, such as digestion, take a back seat to allow the body to focus on the problem at hand.

Cortisol performs positive critical functions in the body as well. It aids in creating memories and helps us wake up each morning and feel alert throughout the day. It assists in managing inflammation levels, sodium and water retention levels, and blood sugar levels. It also plays a supporting role in the metabolism. Our cortisol levels are naturally high in the morning (10–20 micrograms), 4–10 micrograms at 4:00 p.m., and lowest in the evening (less than 5 micrograms), and we do experience a natural burst in the late afternoon, which helps get us through the rest of the day.

“Cortisol is secreted by the adrenal glands, which are little glands on top of your kidneys that look like hats,” explains Kecia Gaither, MD, MPH, FACOG. “Your cortisol levels naturally rise and fall throughout the day. For most people, cortisol spikes in the morning when [they] first wake up, lulls in the afternoon, and may spike again in the late evening.” You know that feeling you describe as a “second wind”? That’s your cortisol cycle doing its thing.

When hormonal levels are balanced, we feel calm and collected, alert and at peace. When they’re out of balance, we might experience various negative symptoms, including fatigue, insomnia, irregular cycles, increased appetite, problems with blood sugar regulation, weight gain, and increased inflammation, to name a few.

How is this exposé on cortisol related to fitness?

When we’re engaged in a strenuous workout, the brain sends a message for the gland to secrete more cortisol than is needed, because exercise puts the body under stress. In fact, research suggests that moderate to high-intensity exercise may increase cortisol levels. Generally, that increase is seen as acute—which means it won’t have long-term effects. However, if we engage in endurance running or cycling, HIIT, weightlifting, bodybuilding or other high-intensity or endurance exercise more than once a day or several days a week, we run the risk of developing chronic high cortisol levels.

This can lead to several negative effects of varying degrees. In the long term, consistently elevated cortisol levels can lead to the health woes we’re working out in order to avoid: blood pressure, diabetes, weight gain (especially in the midsection), osteoporosis, and even fertility issues. Chronically high cortisol levels can increase hormones like testosterone and subsequently estrogen, while also decreasing hormones like progesterone. This can cause disruptions in cycles, as well as acne.

But before we panic or cancel our gym membership, here’s something else we need to know. High cortisol levels don’t necessarily mean we have to stop working out altogether. “The solution is to adjust your workouts. So instead of doing daily high intensity workouts, incorporate yoga and gentle exercise,” says Suzie Welsh, RN, an adjunct professor at Villanova University’s School of Nursing. “Exercise is obviously a very good-for-you thing if done at the right intensity, and the right amount. The goal is find balance in both your workout routine and your cortisol levels.”

To summarize, cortisol, the stress hormone, is commonly regarded as the evil chemical in all hormone-related health concerns. Cortisol in and of itself, however, is not harmful. It circulates throughout the body and is designed to be naturally released during stressful situations to help give us that extra pump of energy when, say, we’re running up a hill or late for the bus. Too much or too little of anything is usually not good, and the cortisol hormone is no exception. Too much intense exercise on a consistent basis can increase cortisol levels to higher than optimal amounts, resulting in the concerning symptoms mentioned above. The key is varying our workouts and listening to the body’s response to the stress we’re putting it under during our workouts. Less is sometimes more.

By Laura Shammah, MS, RDN