BY SAGE MAARANEN
After the 2018 Ironman Boulder, the biggest complaint I heard from athletes was the heat and its relation to a high DNF rate. We are all aware that heavy exercise in high temperatures can lead to medical emergencies such as heat stroke, but so many tend to brush this off as something that could happen but certainly won’t happen to them.
So instead of focusing on heat illness, I’d like to discuss a heat-related issue that should catch any athlete’s attention: Yes, if your body overheats, your performance will be diminished and you will not be able to race at your full potential. Consider this athlete’s story.
Ironman Boulder second-timer Andrea Greger hit the start line prepared to annihilate her previous course time. The day started off well with a 15-minute PR on the swim leg, but by mile 30 of the bike, she knew she was in trouble. It was hot, she couldn’t eat and her pace suddenly slowed. After stopping three times to vomit, Andrea considered pulling from the race. With encouragement from teammates, she kept pedaling, finishing well behind her target pace.
As she started the marathon it quickly became clear that running wasn’t an option. No cooling effort could bring her core temperature down, and she vomited five more times. Although the task felt monumental, Andrea was determined not to quit and continued to march her way toward the finish.
“I remember at mile 25 of the run, a lady told me I was almost there, and I wanted to kill her!” she said. “It was another 20 minutes.”
Although it wasn’t the race she expected, Andrea learned a lot that day — about herself, about racing, and about the toll of heat.
Negative Effects of Heat on Performance
First, a quick physiology refresher. One of blood’s primary jobs during exercise is to carry oxygen to muscles. To cool the body, blood flow is shifted from muscles to the skin in an effort to dump heat. This process makes blood more difficult to pump to muscles to perform their work. The metabolic system used for muscle-fueling must then shift from aerobic to anaerobic metabolism, and VO2Max will be reduced.
Complete USAT article here