Inside an Olympic Athlete’s Cortisol Rhythm During the National Championship

Have you ever watched the Olympics, and amid the colorful pageantry and breathless TV broadcasters, found yourself in simple awe of the human body?

The Olympic Games are where the world’s elite athletes gather to compete. There, audiences have the rare opportunity to witness just how far humans can push themselves. Some athletes have propelled their bodies, unaided, over 8 feet (245 cm) in the air. Others have run 26 miles in just over two hours. Another can even twist her body into a triple-double while suspended in the air for just 1.8 seconds.

After witnessing those types of feats, you may wonder: What does that extreme activity do to your body?

After all, these performances put competitors under tremendous stress. Knowing that, measured the cortisol rhythm of elite athletes during the USA Track & Field Cross-Country Championships in San Diego in January 2022.

And the results were surprising.

Stress’ Role During a Cross-Country Championship

As we reported in January, Olympian Shadrack Kipchirchir who holds the fourth-fastest time in the U.S. 10,000-meter run injured himself in 2021. It kept him from making his second Olympic team.

But in January 2022, he came back with a bang … winning the first competition he’d entered in 294 days, the USA Track & Field Cross-Country Championships.

We wanted to help Shadrack understand how the stress of competition affected his body, so we set him up with Pardigm’s rapid cortisol test during his race week.

Cortisol is your main stress hormone, and you produce it daily as part of your normal hormone rhythm. The average person’s level typically peaks about 30 mins after waking up, preparing them to face the day. Then it steadily declines to its lowest level in the middle of the night. This rhythm helps regulate your sleep-wake cycle, with higher levels keeping you alert during the day and lower levels helping you fall asleep at night. Cortisol also helps manage your glucose, metabolism and more throughout the day.

Of course, this hormone also plays a key role in your stress response. During stressful events (be them mental or physical), your body floods cortisol into your bloodstream, giving you the energy to help you survive.

Ultimately, cortisol plays a vital part in our everyday lives. But it’s particularly important for athletes to watch. After all, one study found that an increase in cortisol prior to a competition may impact athletic performance significantly. Cortisol rhythm imbalances can also lead to muscle soreness, slow recovery and fatigue.

Inside the Body Chemistry of an Elite Athlete

With that in mind, we went to work establishing Shadrack’s baseline cortisol rhythm. This baseline would let us understand Shadrack’s average cortisol rhythm and note any outlier stress levels during competition.

This is critical. We can’t compare his cortisol levels to some general cortisol average because … that doesn’t exist. There is no single universal stress rhythm we should all be shooting for. Your average cortisol rhythm will differ from that of your friend, your coworker or even your parents. Everyone’s baseline is different, depending on their sleep-wake cycle, exercise regimen, diet, overall health and more. So it’s critical to understand your body’s typical daily production before finding any insights in your scores.

We found Shadrack’s baseline by measuring his levels five times on January 6. Then, once we established that, we used Pardigm’s rapid cortisol test to measure his stress levels the day before, the day of and the day after the big race. We tested in the early morning and then in the evening.

Here’s what we saw…

The first chart shows Shadrack’s baseline, with five measurements taken on January 6.

In the next chart, we see Shadrack’s morning and evening measurements from January 5 to 10, around race day.

Finally, we see Shadrack’s morning measurements for January and February. Morning measurements reflect the