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Stress and performance, performance and stress

Cortisol is a beautiful thing. It’s your body’s main stress hormone that, along with adrenalin, creates the fight-or-flight reaction during times of panic. This reaction includes increased blood pressure and breathing rate, a narrowed focus in your brain on the here and now (thus decreasing your memory function), deprioritizing other organ systems like digestion, immune function, growth and tissue repair, and spiking endorphins that increase your pain tolerance. Cortisol pretty much pushes many of your regular body functions aside in order to prioritize your survival. This is pretty critical when, say, you’re being chased by a hippopotamus.

Not so beautiful, however, is the fact that cortisol doesn’t really know the difference between being chased by a hippopotamus and getting yelled at by your boss. Stress is stress, and your body is going to react in the same way. Have you ever had “one of those days?” You wake up late and are racing to work for an important meeting. You get an email that you forgot to pay your cell phone bill and now you owe a late charge. You get in a fender bender pulling out of the parking lot on your way to lunch. You missed a deadline and your boss yells at you in front of your team. Then after work you head to meet your running group for your weekly track workout, and you can’t hit any of your pace targets. Well no wonder! Your body has been pumping out stress hormones all day long and it is just DONE.

Training itself also creates stress in our bodies, which is why recovery is so important. If you ran a marathon one day and tried to run max-effort intervals the next day, you’d be setting yourself up for a disappointing performance at best, and potential injury at worst. Similarly, your track workout after your disaster of a day is not going to go well. Rather than beating yourself up over your poor performance or falling into a spiral of negative self-talk, chalk it up to your stressful day and move on. Understanding what is happening inside your body can help you be realistic about your performance and adjust your reaction accordingly.

Another thing to be aware of is chronic stress. Things like job insecurity, financial hardships, relationship difficulties, a death or illness in the family, moving, or a new job can all cause ongoing stress. When your brain does not get the message that the threat is gone, it does not send the signal to turn off the stress response. Over time, this can lead to high blood pressure, sleep disorders, anxiety, and chronic pain. And don’t forget about some of the responses we covered above – decreased immune function and tissue repair – and you can see how these conditions do not set you up for productive training or performance. If you add training stress to that mixture – say you just started a new job and you’re also training for a 70.3 – you are putting yourself at risk for overtraining, low energy availability, and injury.

Of course, we can’t avoid life stress. The challenge is finding ways to manage stress in a way that allows us to be productive in all the different areas of our lives. And what’s one of the best ways to reduce stress? Exercise! In fact, exercise helps our bodies deal with cortisol more effectively. Long-term endurance training, specifically, helps smooth out the peaks of cortisol in our systems. So the better trained we are, the less dramatic the cortisol response is in our bodies in the face of stress.

As endurance athletes, however, our training often adds an additional level of stress to our bodies. Just like training too hard or too long without ample recovery can lead to overtraining, low energy ability and RED-S, the combination of chronic life stress plus even normally-manageable training loads can lead to similar outcomes. The key is finding the balance that works for you. Being really honest with yourself and your coach about all the things going on in your life can help you integrate your training in a way that will maximize your performance without pushing too far.

Does that mean you can’t train for a race while you’re starting a new job? Of course not. But it is a good idea to be extra aware of your health and performance so you can adjust. You may need a little less intensity or additional recovery time to keep things in balance. Many stressful life events are not planned, but sometimes you may be able to deconflict. For example, if you’re planning your races for the year and you know your spouse is going to have back surgery in the summer, maybe swap your fall race for a spring one so you can train and race earlier in the year and then be fully present for your family during what will likely be a stressful time.

The human body has wonderful abilities to react to stress in ways that can help us when we are in immediate danger. By understanding that reaction, and being sensitive to all the other stressors of modern life (PLUS the training stress that we bring on ourselves), you can start to develop an understanding about how your own body and mind react. The more self-aware you are, the better you can optimize your training and performance and keep your life balance in check. Unless, of course, you encounter a hippopotamus during your next open water swim. In that case, forget the balance – embrace all that cortisol and swim like hell.


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