Cortisol and Weight Gain – Is there a hidden connection?

I’m a cyclist. I got my road bike right after the birth of our first daughter. It’s a handmade beauty from Italy. My bike helps me stay in shape. It helps me explore new places and gets me outside. I have ridden countless miles, including several century rides. I love to ride! Curiously, I’ve noticed my body can struggle with this. If I ride it too much? I start losing my hair. My digestion gets all wonky. (That’s a technical term.) I also tend to start gaining weight. Seriously? Yeah. It sucks. I especially noticed the adverse effects to be true during the pandemic. What in the world is going on?

Well, come to find out, as brilliant as our bodies are, they can’t tell the difference between long bouts of cardio exercise or high-intensity interval training from when a tiger is chasing you. You might not be scared, but your brain calls for the same response in your body.

Your heart rate increases. Your blood pressure increases. Oxygen-rich blood is being pumped out to the major muscle groups, heart, and organs so that you can get away. Cortisol begins to flood the body(1). When cortisol levels are high, glucose levels also increase. Interestingly, when you are in this stress response, muscles stop burning glucose for energy and increase protein degradation. Then cortisol acts on the pancreas, causing a decrease in insulin. What does this mean? Cortisol causes your muscles to stop burning circulating glucose in place of using the glucose stored in the muscles. That means higher blood sugar with lower circulating insulin to help clean it up(2). Get that?

High cortisol = high blood sugar + lower insulin

High cortisol = insulin resistance

Insulin resistance = weight gain, especially around the midsection

The fight-or-flight state also impacts digestion, the reproductive system, and the immune system. All three systems are suppressed – after all, you don’t need to digest that meal you just ate or get pregnant if you’re going to be eaten by a tiger!

Now, layer on the chronic stress of the pandemic. For those who have always turned to endurance sports to keep in shape, these activities can cause us to gain weight now. More than likely, it’s due to a reduction in resilience. Our bodies can only take so much stress. The high-stress season of the pandemic combined with high-stress exercise, and we feel the negative impacts more than positive results(3).

It could also be that I turn 50 in five months. As much as I would prefer not to admit it, I can’t expect my body to do what it did when I was 20.

So have I given up cycling? I have not. I’m just more thoughtful about how I incorporate it. If endurance exercise and HIIT workouts turn on the fight-or-flight part of my nervous system, I have to help turn on the opposite which is rest-and-digest.

Rest-and-digest is a state where we are relaxed, cortisol levels are lower, blood pressure is lower, digestion is improved, and muscles are relaxed. Blood sugar also decreases in this state. It’s a place of homeostasis. Remember our cortisol equation? Now it looks like this.

Decreased cortisol = decreased blood sugar + improved insulin response

Healthy blood sugar + healthy insulin response = healthy weight or weight loss

Now, I ride my bike or Peloton a few times per week, followed by 30 minutes of yoga to intentionally quiet my mind and body, allowing me to transition from fight-or-flight to rest-and-digest. Yoga is an excellent exercise in connecting movement with breath work. The deep methodical breathing in yoga sends a message to the brain to calm things down. On alternating days I will incorporate weights or do power yoga which, although more intense, still tends to keep me in a relaxed place.

And don’t forget the importance of maintaining a nourishing diet, getting 7-8 hours of sleep nightly, and surrounding yourself with supportive relationships to keep those cortisol levels under control.

If you’re struggling with weight gain while continuing to exercise intensely, you might try bringing more balance to your exercise routines. It might also be time to reevaluate your diet. And, sometimes, we just need someone to walk with us to help guide and support the change you and your body need. If this is you, click on the link below to connect with me for a 30-minute FREE consultation.

• (1) https://www.health.harvard.edu/staying-healthy/understanding-the-stress-response#:~:text=This%20hormone%20travels%20to%20the,then%20dampens%20the%20stress%20response
• (2) https://www.ncbi.nlm.nih.gov/books/NBK538239/
• (3) https://www.health.harvard.edu/blog/did-we-really-gain-weight-during-the-pandemic-202110052606