Most of us know that running in the heat makes things quite unpleasant, and even more so, we can identify that the act of running itself feels harder. But why is that, and how can we use that information to help us run our best in the heat? Let’s take a look.
Blood Flow Changes
Our body’s number one tool to cooling our bodies when they start to heat up is to re-direct our blood to our skin to help dump the heat into the environment.
This process, known as vasodilation, allows the blood vessels near the skin’s surface to widen, facilitating heat transfer. With more blood reaching the skin, excess heat is effectively dissipated.
By increasing blood flow to the skin, the body ensures the optimal functioning of its internal organs by maintaining a stable core temperature. This mechanism is crucial for our survival in regulating body heat.
However, with more blood going to the skin, less is going to our muscles and other places in our body (like our stomach). With less blood going to our muscles, they are receiving a smaller delivery of glucose and oxygen, the very things we need to run. Additionally, with less blood flow to our stomachs, food/gels, and fluids are more likely to remain there and cause GI issues.
The hotter it is (or the more humid it is), the more blood is being directed to the skin, making the impact of this greater and greater, thus making running harder and harder.
Want to read more the impact of heat and humidity? Find it in The Training Club!