As we recently hit the unofficial start to summer and transition into the month of June, inevitably warmer temperatures have arrived. Every runner knows the struggles of running in the heat. The average person runs their best when their internal temperature is at or slightly above 100°. At these temperatures chemical reactions are at their most efficient. When the temperature in the air gets higher, it becomes harder for your body to maintain this efficient level. However, your body does have ways of keeping itself cool, and understanding these methods can give you a slight edge come race day.
Radiation is your body’s first line of defense against overheating. Your body burns energy, which creates heat. When there’s a large difference between the heat of your body and the temperature in the air, heat is able to exit the body more efficiently. At warmer temperatures, the opposite is true.
This is why pouring water on yourself during a run can cool you off, the cooler water absorbs the heat your body is producing. While drinking water is important, pouring water on your head, chest, and back can go a long way in keeping your temperature down.
With this cooling strategy, a little can go a long way. Water has a high specific heat, meaning it needs to absorb a lot of energy before changing temperature. An 80° cup of water will still be 20° cooler than your body on race day and can offer you minutes worth cooling.
The next method is Convection which, as runners, is a default tool in the tool kit. When we workout our bodies radiate heat, making the immediate air around us hotter than the surrounding air temperature. However, through movement and wind, air flow can circulate that hot air away from us.
On race day this will be relevant in keeping you cool. Running in large packs can create a localized heat bubble that you don’t want to spend too much time stuck in. Additionally, running directly behind someone might negatively impact the benefit you’d gain by running through still air or a gentle breeze. Prioritize running in smaller groups then you normally would in a side-by-side formation to maximize the convection effect.
Perspiration or sweating is the cooling system people are most familiar with. Sweating is the visual way your body works to physically remove heat. While you can “become a more efficient sweater.” For the most part there’s nothing you can do about that on race day.
Perspiration is an effective cooling method, but it also has its drawbacks. When an athlete sweats they lose electrolytes, which are important to maintain muscle function. Be sure to consume electrolytes during the race in proportion to the amount you are sweating and the length of your race. For example, a runner who runs the half marathon in 70 minutes in 55° might not need mid-race electrolytes, but someone who runs the half marathon in 2 hours in 85° heat will need multiple electrolyte refuels to maintain performance.
As runners, heat can be one of the most challenging conditions we face. But by making small adjustments to race strategy and properly preparing we can reduce its negative effects. Where the temperatures are below 30 or over 90 everyone is dealing with the same conditions. Who has the best race will not be determined by who gets the best conditions but by how you react to the conditions you’re given.