Marathon Blog

Do’s and Don’ts of Hot Summer Training


Many of you are probably training for the Healthy Driven Naperville Half Marathon or 5K (or another fall race). By October, the weather will likely be much more favorable for running a successful race. Unfortunately, your training plan calls for long runs in the summer, during the heat, humidity (and possibly rain and thunderstorms) of July through September. Here are some tips to survive those hot summer runs:

Do watch the weather. First and foremost, watch the weather forecast. If you learn that your long run will fall on a day with less favorable conditions, adjust your plan accordingly (see my backup plan ideas below). Running performance drops below optimal levels when temperatures are above 55 degrees Fahrenheit and will fall 10% or more when temperatures exceed 80. And remember, outdoor runs are never safe during a thunderstorm.

Do adjust to the heat slowly. You can acclimate to the heat of summer, but it will take 5-10 sessions of running in the heat at a much slower pace (and possibly for a shorter distance) than you normally run. Make sure you are well hydrated before and during these runs. Here’s how:

  • Two hours before the run, drink between 17 and 20 ounces of water. About 10 minutes before, drink another 10 to 12 ounces.
  • During the run, drink approximately 7-10 ounces every 10-20 minutes. Adjust this as necessary based on your own ‘sweat rate.’ If your run will last longer than 60 minutes, consider replacing half of the water with an equal amount of electrolyte drink (Gatorade, Powerade, etc.) Mix the water and Gatorade for convenience and digestibility.

Do beware of cramping. When you get a cramp or sudden pain while you are running, slow or stop until the pain subsides. If necessary, stop or walk back to your starting point. Gentle movement (flexing of the foot in the case of calf cramp) will help. Next, figure out what caused the cramping to prevent it from happening again. Check out the most common causes and suggested remedies:

  • Heat and/or dehydration. Is it warmer than it has been in recent days? Did you drink less fluid than normal? If either of these is the case, you may be dehydrated. Next time you run, pay attention to hydration. Drink 17-20 ounces of water 2-3 hours before you run. Then in the 30 minutes before you head out, slowly drink 10-12 ounces of water. If the cramping is accompanied by other symptoms of heat illness, stop, and follow the tips in the heat illness section below. 
  • Inadequate warm-up. If it’s not warm, you’re well hydrated and you were running at a moderate pace, it is possible your cramping came from an inadequate warm-up. Walk for 5 to 10 minutes and do some movement exercises before you begin your runs.
  • Overdoing it. If cramping occurred while doing speed work, it is possible that you were going too fast for your current conditioning or you ran too fast too suddenly. Next time, try going a little slower and/or do a more thorough warm-up before attempting the speed work.

If cramping persists into the next day or recurs the next time you run, consult your doctor or running coach. 

Do know the signs of heat illness. If you run outside in the heat, watch for signs of heat illness such as nausea, fatigue/weakness, dizziness, cramping or confusion. If any of these occur, stop immediately and cool your body by going indoors, hydrating and putting cool water on your head, neck, and body. If symptoms persist, seek medical attention. For more details on heat illness, check this Healthy Driven blog.

Do beware of ticks. Hot weather means ticks. The Centers for Disease Control & Prevention (CDC) has warned of an abundance of ticks this season. Fortunately, they also offer great advice on avoiding ticks.

In addition, here are my own tick-related tips for runners:

  • Wear light clothing so you can spot ticks, but not white clothing as ticks are attracted to white clothing.
  • Wear bug repellent. The CDC offers some natural options if you are not interested in wearing chemical sprays while running.
  • Run on paved trails or crushed gravel rather than on dirt trails. If you must walk through mowed grass, pick up your feet rather than shuffling.
  • Avoid running under trees. Ticks can drop onto you from trees as you are running. If you feel something small hit you from above, make sure you brush it away.
  • Make sure your socks are tight to your feet and ankles. Some types of socks (like roll-down anklet socks) provide a reservoir for ticks to fall between the sock and your ankle.
  • Follow the CDC recommendations about checking your clothing and where on your body to look for ticks, and shower right away after running outdoors. Finally, shake out your running shoes and keep them outside between runs.

Don’t forget your backup plan. If it looks like your long run is planned for a hot, humid day or a day with forecasted thunderstorms, consider these options:

  • Switch the day. Consider moving your long run 1-2 days earlier (or later) if your schedule allows. Your long run is your most important run each week, so moving or adjusting a couple of your shorter runs won’t hurt your training. The goal for the week is to have a successful long run.
  • Start early/switch the time. Starting at 5 a.m. can make a big difference in the amount of heat and humidity you face during your long run. Getting some or most of your long run in before the sun rises can improve your chances for success and this time of year, sunrise is very early. Similarly, switching the time of your run to avoid thunderstorms will keep you safe. The weather app on your phone can be configured to detect lightning in your area; seek shelter immediately if lightning strikes in your area during a run.
  • Seek the shade. A shady course can make as much as a 10-degree difference in ambient temperature and will help you to avoid the heat. Remember, shade is not an option to avoid thunderstorms.
  • Go indoors. Consider doing your long run on a treadmill or indoor track. It might be more tedious, but the conditions will be much more favorable. This will allow you to achieve your goal training pace more successfully than running outside in 90+ degree heat or during bad storms Avoid boredom by listening to music or a podcast or running with a training partner.

Don’t push your pace in the heat. If all else fails, you have no other option and you must run in the heat and humidity (and you are not acclimated to the heat), hydrate (as discussed above) and slow your pace. One of the main purposes of the long run is to teach your body to handle exertion and energy expenditure over a long period of time. In the heat, exertion levels and energy expenditure will be much higher for a given running pace. Hydrate properly before your run and go as slowly as necessary to complete your long run, taking frequent hydration breaks (including both water and electrolytes) and walking breaks. If you have extra water, pour some on your head and neck to keep cool (don’t use electrolyte drink). Don’t worry about your pace or time; the training effect is occurring and in your next long run, weather permitting, you will do and feel much better. 

Don’t let sweat get into your eyes. Sweating is important in running; it’s how your body keeps cool. You don’t want to prevent or discourage sweating. To keep sweat out of your eyes, try a headband or an absorbent hat. There are baseball-style running hats on the market that do a good job of absorbing sweat and shield your head from the sun. Some newer hats even use fabrics with cooling technology such as UA Iso-chill.

Don’t suffer from chafing. Chafing can really be an issue in the heat due to sweating. For chafing you already have, try a healing ointment such as Aquaphor. To prevent chafing going forward, try an anti-chafe balm such as Body Glide. Apply this to any areas where your clothing rubs against your body (or you have body parts rubbing against body parts.) Common areas include inner thighs, inside of upper arms, bra lines/seams for women, nipple area for men, etc. Apply before every run but especially for longer runs. Anti-chafing products wash off very well in the shower after your runs.

Don’t ignore hot spots and blisters. Running in the heat can aggravate blistering due to the extra sweating that occurs. To minimize blisters, make sure you have a pair of properly fitting running shoes. If you are uncertain, go to one of the local running stores (Dick Pond, Road Runner Sports, Naperville Running Company). Next step, socks. I personally prefer double-layer socks (Wrightsock is the brand I wear) as they are virtually blister proof. Body Glide or a similar anti-chafing product applied to the toes and other hot spots can help prevent blisters as well. For blisters you already have, if they aren’t serious (no broken skin), Compeed or similar blister cushions provide great relief. If you have already developed more serious blisters with broken skin and/or infection, seek medical attention.

Stay patient and confident through these hot summer long runs and when the weather cools, you will reap the benefits of difficult training in summer weather.

Laurie Lasseter Marathoner
ACE Certified Personal Trainer
RRCA Certified Running Coach
Edward-Elmhurst Health & Fitness