When race day temperatures spike into the mid-70s or higher, your entire approach to the race changes. Racing in the heat presents a whole host of challenges: core temperature regulation, hydration, higher perception of effort, and higher heart rate. You simply cannot race the same in hot weather as you can in ideal conditions. That does not mean you are doomed to have a bad race. You can still race your best for that day, with these tips for racing in the heat.
Acclimation and heat tolerance factor in as well. If you are racing in the heat on the first hot day of the year or traveling to a destination race, the temperature will be more of a shock to your system and you will need to adjust your race strategy more.
Pre-Cool and Pre-Hydrate
You do not go into a marathon or half-marathon with an empty stomach and expect to run well. Instead, you eat before the race so that your body has readily-available calories and carbs to convert to energy. The same applies to hydration and cooling; you do not wait until the race to start.
Pre-hydration begins days before a race. You want to drink enough to maintain optimal hydration. Don’t guzzle so much water that you are running to the bathroom every hour. Aim for enough that your urine is light yellow and that you do not feel excessive thirst. In the morning before a race, have a sports drink to hydrate and support sufficient sodium levels.
Pre-cooling helps you maintain a lower core temperature before the race. You can bring a pack of ice with you to place on your pulse points (neck, wrists, etc), in your hat, or on your core before the race. You can dunk a buff or cap in cold water and freeze it the night before. Even a dump of cold water on your head will help!
Dress for the Heat
In a road race, you encounter both heat from the sun and radiation from the asphalt. You will feel hot no matter what, so dress to minimize any more heat absorption. Wear lighter colors rather than black or dark colors, opt for wicking fabrics, and wear a cap or visor to shield your face. Avoid wearing any more layers than you need; those arm sleeves advertised as cooling may actually do more harm than good.
Head to the Trails
The roads are not the only option for racing. If you really want to race in summer without dealing with scorching heat, race on the trails. The ground reflects less heat than pavement and the shade from trees provides protection from the sun. Trail races are generally more laidback than road races as well. You can’t compare a trail race to your road PR so that automatically removes any self-imposed pressure.
Nervous about the trails? These tips will help road runners transition to the trails.
Hydration is important for summer running: the hotter it is, the more fluids you need. Your body needs fluids to regulate temperature, and if you sweat too much, your blood volume thins and your performance declines.
However, water is not the only thing lost. You lose sodium in your sweat as well. As an electrolyte, sodium aids in your body’s absorption of water. It also prompts thirst signals so that you don’t forget to take in fluids.
You do not want to swing to the other side of the spectrum, however. Excessive consumption of fluids (especially plain water without sodium) increases the risk of hyponatremia. Hyponatremia is a dilution of blood sodium levels and requires medical attention. Symptoms include headache, disorientation, lethargy, and nausea. You can minimize your risk of hyponatremia
When racing in the heat, go into the race with a hydration strategy. In most scenarios, it is better to hydrate early and often, but don’t overhydrate out of precaution. Use each aid station as an opportunity to assess your thirst. Grab a cup of sports drink or water from each aid station and drink to thirst. The important thing here is drinking to thirst: that could be a sip, the full cup, or choosing to just dump the water over your head instead. Don’t ignore your thirst, but also don’t mindlessly guzzle fluids.
Plain water is certainly better than dehydration. If possible, take in fluids with electrolytes, whether from the course aid stations or you bring your own. In at least my opinion, it’s worth risking GI distress from the course Gatorade if it means avoid dehydration or heat exhaustion.
Stay Cool during the Race
When I coach an athlete through a summer race, I usually suggest mid-race cooling strategies. The simplest one: dump water on your head and back of your neck. Grab an extra cup of plain water at an aid station and dump it on yourself. The water on your skin, especially on your head or pulse points, will help regulate core temperature. If it’s a really hot day, soak your cap or even shirt with water during the race.
Scale Back and Focus on Effort
Chances are, you are not going to run a huge PR in 80-degree weather. The heat places higher stress on your body than the ideal racing temperature of 40-55 degrees. Focus on running a smart race first (no finish time is worth heat stroke) and competing your best for the conditions of the day second.
Because the effects of heat accumulate as you run, you want to start slower than normal. If you are focusing on effort, this means restraining yourself slightly to conserve energy for the second half, rather than starting off hard at race effort. If you are monitoring pace, start 15-30 seconds per mile (depending on the temperature and your heat tolerance) slower than you want to run. In the best case, you stay cool and can run strong in the second half. In the worst case, you run a slower time overall – but avoid crashing mid-race from the heat.
Keep yourself out of your own head. Set your GPS watch so it shows you only time or distance, not pace. Pay attention more to your body’s signals than what your watch says.
If you can’t get over the number, use the VDOT calculator to compare your race time in the heat to your “normal” race times. This calculator does not account for individual variance in heat tolerance, but it can provide the numbers-obsessed runner with a more concrete idea of how the heat slows you down. For example, a 45-min 10K runner will likely run 46 minutes in 75-degree temperatures and 47 minutes in 85-degree temperatures – almost 20 seconds per mile slower.
Be Aware of Alarming Symptoms
Heat exhaustion, heat stroke, and hyponatremia are all serious concerns with racing in the heat. If you begin to experience nausea, light-headedness, dizziness, unquenchable thirst, muscle-twitching, or other alarming symptoms, stop running and go to a medical tent.
How do you manage racing in the heat?
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