Heat and humidity are two of the most uncomfortable conditions a runner can face. But not only does warm-weather running feel harder, it actually is harder too. In hot and humid conditions, blood flow is redirected to the surface of your skin where it can more effectively dispel body heat. This means your heart has to pump faster to circulate enough blood to keep up with resting-level energy and oxygen demands on top of cooling demands. All this, before you’ve ventured even a step from your couch. When you go for a run in the heat, your muscles’ energy and oxygen needs multiply, and your body produces extra heat which it must work even harder to get rid of in a hot environment. This results in your heart rate increasing even further beyond its pre-elevated, warm-weather state. And the sun likely beating down on you throughout all of this will only make you feel that much more uncomfortable.
But let's take a step away from the science talk. What all of this means is that the 9:30 minute mile pace that felt like a breeze back in May might feel closer to an 8:30 pace by the end of June, and if you don’t understand why (and sometimes, even if you do) it’s easy to get discouraged. But summer comes every year, and it sticks around for a whopping 92 days. So, if you’re serious about getting your miles in during the summer season, you’ll need to find a way to cope–and maybe even thrive–in less-than-ideal conditions.
When To Run
The easiest way to cope with the heat is to avoid it altogether. The coolest time of day is just before and slightly after sunrise. Yes, you’ll have to get up at the literal crack of dawn, earlier even, but it’s the easiest way to beat the heat. An added bonus: not only is this the most comfortable time of day to run, it’s also the safest time of day for your skin because you’ll face the least amount of UV ray exposure. However, if even the idea of this early bird schedule seems absurd to you, the next best time to hit the asphalt is at the end of the day. While it will still be hot around dusk, it will likely have cooled down a few degrees and you won’t have to deal with the sun beating down on you. Whether it’s at the end of the day or the beginning, the timing of your run will be determined by your own preferences and schedule demands. Just keep in mind that UV light is at its strongest between the hours of 10 A.M. and 4 P.M., so try to avoid this window if you can help it.
What To Wear
When selecting an outfit for your next warm-weather run, you’ll want to consider the breathability, fit, and weight of each garment. Look for clothing that is breathable, looser in fit, and lightweight. In terms of material composition, a synthetic fabric like polyester is great for running in the heat because it is both breathable and moisture wicking. Where natural fibers like cotton will absorb your sweat and stick to your skin, polyester allows your sweat to move through its pores and across the garment’s surface so that it can evaporate on the outer side, away from your skin. Nylon and spandex are also synthetic and moisture wicking materials, and while they’re not particularly breathable, they are necessary for providing stretch. Therefore, a polyester and nylon or a polyester and spandex blend will provide you with the best of both worlds: stretch and comfort plus breathability and moisture-wicking properties.
In terms of fit, you’ll be most comfortable running in the heat if there is room between your clothing and your skin for air circulation. To aid in this pursuit, look for garments with a relaxed fit, or if they run on the slim-fitted side, consider sizing up. Another feature to look for in your garment is a lightweight and open knit structure. If the fabric is thin and has small holes or gaps, air will be able to freely circulate in and out as it warms up. One crucial note here is that if your summer running clothes do have a more open knit structure, you’ll want to make sure to wear SPF underneath them. If a cool breeze can get in, UV rays certainly will. For additional sun protection, you may also want to try running gear with ultraviolet protection factor (UPF), which acts similarly to SPF to block UV radiation. A UPF rating of 50 means that the garment only lets in 1/50th of UV rays. In other words, it blocks 98% of the UV radiation coming your way. Garments with UPF will have a closed-knit structure to prevent the sun from getting through, but they can still be incredibly lightweight, and therefore make great options for summer running. And unlike sunscreen, you won’t need to reapply! Finally, don’t forget to accessorize with sunglasses, and a visor or hat for additional comfort and sun protection for your face and eyes.
(Check out our Runglasses, to help protect your eyes from UV Rays during your run session)
How to Stay Hydrated
Proper hydration starts hours (and even days) before you head out for your run, so the best way to up your hydration game is to build a habit. If you have to work to hydrate, you probably won’t. Instead, keep a water bottle on your night stand and at your desk or in your bag so that it’s always within reach. If it’s in your line of sight, you can easily remember to take a sip of water whenever you’re in between tasks or just getting up to move around. If you don’t like the flavor of water, you’re not alone. Try some fun additions or substitutions like coconut water, a splash of juice, lemon, or an electrolyte powder or tab. Not only will these improve the flavor of your water, they’ll also help you hydrate more effectively by replenishing your electrolyte stores which are depleted by sweating during vigorous activities. Muscle spasms and cramps are both signs that you may be dehydrated or running low on electrolytes. If you’re drinking plenty of water and still experiencing these, it may be time to add an additional source of electrolytes to your routine.
Once you’re out on your run, continue to hydrate. This is especially important if you’re planning to run more than a few miles, or if it’s particularly hot. If you’re running in intense heat or sun, it’s a good idea to take breaks periodically in spots of shade, and you can use these to rehydrate with some water or a sports drink. To make your fluids more easily available, you may want to wear a hydration pack or vest, or simply carry a water bottle along with you. Hydrating is rehydrating, so drink plenty of water when you get home too. A big glass of lemonade or water will likely be the first thing you’re craving, but you can also refuel while you rehydrate. A smoothie is a great post-run snack, and fresh fruit is also relatively high in water content, so these are great ways to build back energy and hydration at the same time.
Tips to Stay Cool
We’ve already covered scheduling, wardrobe, and hydration, but what can you do once you’re actually out on your run? First off, if you aren’t running in the early morning or after sunset, try to stay in the shade whenever possible. If you live in a coastal area, consider driving to the beach for a route that has a nice sea breeze to keep things cooler. The added bonus here is that you can always shed your shoes and socks and take a quick plunge in the ocean to cool things off. In general, when running in the heat–extreme or not–taking breaks is important. As we’ve mentioned, you can use them to drink some water, and check in with yourself to see how you’re feeling. If you have a watch that continuously measures your health data, you can also monitor your heart rate and compare your performance results with what you’d expect to see. If you’re really struggling and your heart rate is even faster than what you’d expect, be sure to slow things down, perhaps transitioning to a walk/ run for the day. Basically, don’t be a hero. It’s also good to know what kind of heat you’ll be experiencing when you go out for your run. In general, a dry heat will be more comfortable than a humid heat because your sweat will evaporate quickly and cool you down more efficiently. If humidity is high and temperatures are too, your sweat won’t be able to do its job as efficiently, and it might be worth considering an off day, or planning a trip to an air conditioned facility instead. Heat exhaustion and heat stroke are always a concern when exercising in warm environments, so know what signs to look for, and always have a phone with you in case of emergency. You should also know your route, and maybe plan to have a few air conditioned stops along the way for needed breaks.How to Stay MotivatedThe good news: it gets better. If the heat you’re experiencing is long term (think seasonal, rather than for your week’s vacation in Miami) your body will start to acclimate over the course of a couple of weeks. That being said, no matter how much you acclimate, it simply isn’t possible to run at your optimum speed without optimum conditions. Try looking at your summer running as a training opportunity to continue to build base miles and keep yourself conditioned. Instead of getting down about not hitting specific times, give yourself credit for just getting out there and putting in the miles and effort. Because it feels so much more taxing, running in the heat can be a lot more mentally draining, so try to mix things up and keep it light and fun. Plan runs and hikes with friends, go to the beach or the mountains, and don’t get bogged down if you don’t feel up for a run. Soon, you’ll learn to adapt based on how you’re feeling–a valuable skill regardless of the conditions. There are a lot of things heat can teach you. Perseverance, staying in touch with your body, how to monitor and react to your heart rate, how to stick to a schedule, to sometimes take it easy. These are all things runners must learn and master for themselves, and summer can be a bit of a crash course. Learn from it, and try to enjoy it. And finally, a closing note.The best news: even the longest, hottest summers eventually come to an end.