As we head in to another SoCal summer, don’t let the the summer heat turn your training and racing into an unusually tough experience. 

As we head in to another SoCal summer, don’t let the the summer heat turn your training and racing into an unusually tough experience. Take a hard course and throw in the sun, humidity and hours of activity and the body is subjected to unaccustomed strain. All this means you need a plan to overcome dehydration and overheating so that you can race to your true potential.

In the heat, sweating is your body’s self-cooling mechanism. Increased blood flow to the skin allows excess heat to be shunted out of the body. However, there is only so much blood (& the oxygen it carries) and the more that is directed towards the skin, the less there is available to fuel your aerobic system. Furthermore, the fluid loss from sweating and the electrolytes that go with it also bring about other serious issues such as dehydration, cramping, poor nutrition absorption & hyperthermia. Dehydration by as little as 2% can reduce performance by as much as 20%! Muscle and intestinal cramping can reduce the fastest pace to a crawl and Hyperthermia can put you in the medical tent, so how do you train and race in the heat?

Firstly you need to acclimatize to your environment. This can take around 10 days for most people traveling to hotter climes. When you first arrive at your new destination you’ll notice several things. Firstly, your heart rate will be much higher than usual at the same paces. (This can be up to 30% higher!) Secondly, your sweat rate will be up and lastly, you will notice that you fatigue more rapidly. The strategies required here are simple. If you are racing you should be in taper mode so reducing workout duration while your body adapts is not a problem. Also reduce the intensity of sessions until you start to see your heart rate returning to normal levels for you. Start by training at the normal prescribed heart-rates (which will mean an “easing off” in power and pace) and use the heart rate as a guide of “total body stress”.

Furthermore, keep off your feet and keep in the shade as much as you can. You do need to spend some time in the warmth of your new environment to help the acclimatization process but you also need to not stress your system and get dehydrated prior to race day. Not long ago it was thought that you should keep the air conditioner off in your room to aid acclimatization but now studies seem to show that this actually does not help. Instead, train in the heat of your race location and recover and sleep well in comfortable surroundings.

Before traveling to an event you can try to get used to hotter environments. This may mean wearing more layers when exercising in the heat or doing some indoor training with less cool air. You must though stay super hydrated during this time and watch heart rates and total body stress very carefully. The goal is to help acclimatization but not to reduce the effectiveness of your training.

Hydration is a key strategy to keep core temperature down and to keep blood volume high. Pre-race, water alone doesn’t cut it. Many people find that they make far more frequent bathroom trips when they consume just water and the end result can be the loss of vital electrolytes in your urine and an excess of this is the main cause of Hyponatremia. Instead use a weak carbohydrate and electrolyte drink in a 3% solution (that’s 30 grams Carbohydrate in every litre) as your pre-race/ between training fluid. You can use any drink as long as it is 3% solution + electrolytes. The small amount of carbohydrates along with sodium and potassium helps absorption by the cells. It also allows you to top up your carbohydrate stores without causing a negative insulin spike – think of it as subtle, stress free carbo-loading. Another system that I have found to work very well is “glycerol loading”. This allows more water to stay in the cells during the hyper hydration process. The one product that I have found to work extremely well for this is “liquid endurance” from Hammer Nutrition.

During your event use a 6-8% carbohydrate and electrolyte solution to supply your energy and hydration requirements. The studies say that you can absorb no more than 1 liter per hour during exercise, though from data I have gathered from some of my athletes who race the Hawaii Ironman, many can take in much more than this as the sweat rate is so high. Dutch Pro Triathlete Frank Heldoorn (a top finisher throughout the 90’s) frequently told me “If I don’t need to pee by mile 70 on the bike I know something is wrong”. Test what you can handle during training. My experience tells me that it’s often not the volume of fluid but the concentration of the solution that slows absorption and leads to “fat belly” syndrome.

Electrolytes are often the missing factor and many people suffer cramps and bloating from not taking additional electrolytes in during the race. There are plenty of great electrolytes products on the market so test what works best for you in training. You can get capsules or tablets and either are fine – if you prefer not to have to deal with capsules during the race you can split open the capsules and add them to your race drinks but be sure to shake the drink each time before you drink it so all the powder does not end up at the bottom of the bottle. I have known athletes to take up to 1400mg sodium an hour in hot races when their sweat rate is high. Test in training what you need first. A simple guide is that any sign of cramping means you need more and nausea may mean that you’ve overdone it.

During the event, soaking your body and working limbs in water helps let the heat evaporate from the skin more quickly than if the skin is dry. Just be careful not to soak your feet and socks when running, as you don’t want to do anything to add to the chances of getting blisters. Furthermore, don’t underestimate the benefit of the right clothing, eyewear and headwear. Light colored clothing that allows heat to escape is vital. Black may look cool but it’s far from it when the sun is beating down! Darker than usual sunglasses and swim goggles reduce stress on the eyes and a helmet with good ventilation and a run cap or peak has been proven to be cooler than a bare head. For long training rides you can do well with a frozen camelbak. This helps keep you cooler for longer and is a great way to carry your liquid. Post race and training, if you are planning on a quick recovery, take time to take the IV offered to you. At the same time for the next few days, maintain 3% solution intake until you start to feel fresh once again. Taking 10 minutes to sit in a cool lake or the ocean will also aid recovery by reducing core temperature and reducing the swelling of your limbs. If you are feeling truly sadistic you can even make your own ice bath and take a 10-minute dip!! All in all, the key to success in the heat is to have a plan and be sensible. Treat it as a key part of your preparation and use these tips from the pro’s to make your day go the way you intended it.