It’s Spring time in Houston, which means it’s currently worse outside than any summer in a northern state (don’t let anyone moving here forget that! We have a reputation to uphold!). 

This means even though we’ve got A/C, you’re gonna have to step outside for a run or two for your daily WOD. 

How Your Circulatory System Handles Exercise

So let’s set the scene!

You’re about to start the workout Murph. Coach Katelyn says “alright Sphagettis! It is Murph Day! For your warm-up…” and you begin your warm-up. 

As you start to move you feel that weird groggy feeling, where your body really doesn’t wanna move and as you move on through the warm-up, it gets easier and you remember why you enjoy the feeling of working out. During this time your body went through the process of Vasodilation. When you started that first movement in the warm-up, your body realized you are working out and started sending signals to your head and lungs that you’ve gotta get ready. 

Your body then pulled blood flow away from the skin for a moment before ramping up blood flow and filling your blood vessels up (that’s the vasodilation part). 

Once you reach that peak blood flow, your body starts to sweat! Why? Because now your internal temperature is higher than the ambient air around you and the body needs to regulate your temperature. 

You’re Actually Quite Hot

That average human is at about 98.6 Degrees Fahrenheit. As we exercise we actually get all that warm blood up near our skin and we participate in a process called convection. When it is cold outside, we heat up the air around us, this is why you sweat when you exercise indoors still (when it’s hotter outside, the opposite is true). In fact, when we exercise, about 80% of all the energy we use, goes into the heat our body expends through evaporation (sweat) and convection (heat exchange). That leaves just 20% for movement and body processes!

Now, convection is a passive process that our body goes through. As we make heat, it just escapes from our bodies and we don’t really have to do much else to facilitate that. But, sweating requires our bodies to send a little bit more blood flow to our skin to help out. When we exercise in a cold environment, you send less blood flow to the skin. In a hot environment, you actually have to use some of that 20% to aid the cooling down of your body.  

When this happens, we see an increased heart rate from your body to try to keep up with the demand, but there is a threshold at which you can perform. This means that when you go to exercise outside in the heat, you have a lowered capacity for performance. This is why if you were to perform the same exercise indoors at 72 degrees and outside at 90 degrees, you would most likely see a better score on the indoor workout.

The Effect Of Heat On Fitness Goals

Since our bodies respond and adapt to the situations we put them in, you actually will adapt to exercising outside quite a bit through the production of plasma. The process takes about a week and then you won’t feel like you’re getting punched in the face with overheating when you step outside. Along with this, making sure you remain hydrated is crucial to staying healthy and not suffering from heat exhaustion in this Texas heat! 

Even though we adapt, we still won’t be able to push quite as hard as we would in a colder climate. For us everyday athletes, this hardly has a meaningful affect on our progress. As long as we are consistent and push ourselves, we are gonna see PRs throughout the summer.

For elite/experienced athletes it will be harder to see those PRs as the progress made by these athletes is usually smaller. For these athletes, tying a previous time for a WOD hit in the winter might actually be a PR effort. 

Regardless of which type of athlete you are, just remember that feeling like you’re not able to push as hard in the heat is totally normal. You just have to remember to stay hydrated and push your limits within your threshold. Working out by feel is always a safe bet! If you ever feel like the heat is too much in a WOD, dial back the pace or take a second and recover! If you feel light headed, stop the workout and let your coach know. We can get ya somewhere cool, help you recover, and make a plan for next time to reduce the likelihood of overheating.