Triathletes Beat the Heat

by Sally Drake

Race season will soon be in full force and local St. Louis athletes are dreading the usual blasting heat and suffocating humidity. The summer sun can prove to be a challenge just walking from your car to your house! Training for endurance events such as triathlon or running races will test even the toughest athletes when the temps exceed 90 degrees with humidity. So, how can you train effectively and safely in these difficult conditions, and what if it is like this on race day? Here is some information and a few suggestions.

Get Out There
Triathletes are tough, but many turn to the air conditioning and treadmill or spin bike when the heat is extreme. It is important to acclimate to the heat slowly, so an option would be to do half of the run indoors and half of it outside, eventually completing your entire run outside. Waiting until race day to experience working out in hot conditions will sweaty-runnermost likely prove to be detrimental in your results. So, get used to it! This will prevent you from serious health risks brought on by the heat: increased fatigue, muscle cramps, nausea, shortness of breath, and feeling faint. Every athlete takes the heat differently, you will find out how sensitive you are and can improve your performance in higher temps with the proper

The Window of Time to Acclimate
To achieve the benefits heat acclimation, you don’t need to suffer through months of misery! The common laboratory based heat acclimation protocols have athletes spend 7-10 days for about 1 hour a day in a heat chamber. The important thing is, this duration should match the time of the race as possible, longer is not better here. Important to note: the effects of training in the heat will decay in 1-3 weeks. So, you will be doing your heat training during your taper. If it is a very important race and you are living in cooler temps than what you will find on the race venue, consider traveling to the race several days before to train in the same heat and humidity that you will be racing in.

We are all in it Together
Studies have shown that a hot and humid environment can affect even elite athletes. Also, the effect of heat on performance is different for each sport. There is less effect from heat on the bike than the run, for example. Much data exists showing a link between performance and ambient temperature. Suggestions from various authors claim performance impairments of between 1.6 and 3% in marathon (so again, different on the bike) times for every 10 degrees above 55 degrees Fahrenheit. On race day, we are all out there together, all struggling with the same weather conditions. So, it may be slowing you down, but everyone else on the course is slower as well. Bill Henderson, M.D., explains what happens to our bodies in the heat:
“When we exercise, we produce a great deal of heat. One of the principle ways that we get rid of this excess heat is through sweating (evaporative heat loss), as well as conduction and radiation of heat from our skin. To achieve this, our bodies have to send a considerable amount of blood to the skin. This blood is therefore not available to perfuse working muscles and deliver oxygen to them. So a portion of our blood volume is essentially no longer able to participate in oxygen delivery and energy formation in our exercising muscles. The greater the amount of heat that we need to dissipate, the greater the proportion of blood that is diverted to the skin (up to a point – this can’t increase forever).What is necessary for cooling isn’t the hemoglobin (the red blood cells in blood) but the plasma, which is essentially water with a number of different proteins and electrolytes in it. However, your body can’t separate the red cells (which are the oxygen carriers) from the plasma – they all go along for the ride to the skin.”

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