With temperatures soaring to 24°C during the 2018 London Marathon, Dr. Jeffrey Aldous, a lecturer in exercise physiology at the University of Bedfordshire, offers advice on how athletes should deal with high temperatures.

The London Marathon 2018 was the hottest since records began, with runners facing even more challenges than usual along the 26.2 mile course. As an expert in the field, Dr. Jeffrey Aldous, a lecturer in exercise physiology at the University of Bedfordshire, believes it is vitally important that as athletes, you are aware of how to deal with high temperatures to achieve peak performance in a safe manner.

Knowing your body
“Our bodies function very differently at elevated temperatures and every athlete benefits from knowing the basics,” he explains. Dr. Aldous stresses the importance of cooling down whenever possible, giving you a higher threshold for heat gain.

“Before the marathon, make sure you use an ice pack or an ice vest to lower your core temperature,” he says. “The use of water sprays to the face might also help reduce your perception of the heat, making you feel cooler and more comfortable.”

One certainty during any race is that water is going to be lost through sweating, the most effective way to lose heat. While running in hot conditions, this is intensified as the body fights to stay cool, so it’s important that you replace any fluids lost.

“Sports drinks have certain advantages over water,” Dr. Aldous adds.

“Depending on which drink you use, you can replenish your store of carbohydrates and electrolytes, which you lose by sweating, using a sports drink.” That said, you should be careful not to drink too much.  

Diet is key
As with any physical activity, it is crucial that your body is properly prepared. Carbohydrate stores are used up much faster when it’s hot as blood is diverted to the skin’s surface, meaning the heart has to work in overdrive to provide muscles with oxygen. Increasing carbohydrate intake gives the body extra fuel, ensuring that all the energy needed to finish a race is provided.

“Carbohydrates are our main source of fuel, and we use more of them in the heat,” Dr. Aldous reveals.

“It is therefore a good idea to eat slightly more than usual before exercising in the heat, although not to the extent that it increases your weight or makes you too full.”

Clear skies may be a good sign to most, but on race days, they can cause serious problems. Too much direct sunlight raises core temperatures and can quickly tire you as the body works harder to cool down. One simple method to offset this is by choosing appropriate clothing.

“Dark colours absorb heat more than light colours, so you would be well advised to dress in light colours to avoid overheating,” he adds. This can be complemented by opting for lightweight, wicking materials.

Less haste, more speed
On particularly hot days, you should consider taking things more slowly, or even take a short break during the race to allow your core temperature to drop. British distance runner Callum Hawkins is well aware of the benefits of knowing your body’s limits. Representing Scotland, the young runner led the marathon at the Gold Coast 2018 Commonwealth Games until his body gave way under the strain of running in elevated temperatures.

“I found out the hard way to be honest,” he admitted after the scare. “Adjust your pace – and don’t keep pushing like I did.”

Finally, Dr. Aldous highlights the benefits of using the environment to your advantage. If there is stretch of the course covered by trees, head towards the shade. This will help reduce the impact of direct sunlight and allow the body to cool down.

“Running in the shade will cool you down, as will finding a decent breeze,” he advises. “Finding either of these things is only partially in your control as you have to follow the marathon route, but enjoy these things if you find them and remember that they will also allow you to speed up.”