Summer Heat Training for Runners: How to Slow Down Now and Run Faster in the Fall
How To Survive Summer Training
This time every year I get the same text from a few of my runners, “How do I train effectively in the summer heat?” It only takes one way-too-hard effort at a runner’s typical easy run pace to ask what on earth made them so slow. The obvious answer is always the same: the heat. The reason heat training works isn't magic — it's blood. Running in the heat forces your body to expand its blood plasma volume over time, which means more oxygen delivery to your muscles once the temperatures drop. That suffering you feel in July is essentially a deposit. Fall racing is when you cash it out.
A suddenly high heart-rate during what is supposed to be an “easy 30 minute jog” would make any stats-oriented runner nervous, but the by-product of running in the heat will likely be a contributing factor to your next big breakthrough. Conventional wisdom preaches a “no pain, no gain” mentality that might tempt an every-day runner to do all of their weekly running during the hottest hours of the day. This is a recipe for dehydration, muscle cramps and improper recovery. So how do you train effectively in the summer heat and how can you take advantage of the benefits of heat training? Here are a some ideas:
Intermittent and slow introduction
Any time you introduce a new training stimulus, moderation is the key. The most successful runners in my program are not always the ones who train the hardest, but instead they are the ones who adapt to the training properly. Running in the heat requires your body to utilize blood as a cooling mechanism which reduces the amount of blood being used by your muscles. This is why your heart rate increases so much during summer running. Like all stimuli, your body will adapt. In this case, the primary adaptation is by expanding blood plasma volume.
In order to properly adapt, introducing heat running slowly while prioritizing cool running might just get you acclimated to the heat faster than going cold turkey. (Or maybe hot turkey?) Treadmills and early morning running will be your bread and butter during the sweaty summer season. Start with one or two runs a week in the hotter hours and do the rest during the cool mornings or on an indoor treadmill. After two or three weeks of the occasional hot run, increase your number of hotter runs to 3. As long as you keep the pace slow and your cool days controlled, your body will make the adaptation. It is important to remember that even though you are physically adapting to the heat training, you will likely continue to feel the effects of the heat during your training. You may only see the product of your hot summer running when things finally cool down in the fall.
Effort/heart rate based running
The #1 complaint I hear surrounding effort based running is that the runner ends up running “so slow!” I find it important to remind runners that, physiologically, your body does not measure total distance run or pace at that matter. A more accurate measurement of running as an exercise is time and effort. A four mile easy run at 9-minute per mile pace means different things to different people it terms of running science. However, 36 minutes spent at 70% of your max heart rate is a perfect easy run! The summer heat will do two things: First, it will increase your heart race without an increase in pace. Secondly, it will increase your effort to sustain normal paces. Easy effort in 90-degree heat might be a whole 90-seconds slower per mile than you might run in cool weather. Some runners find themselves slowing their run to a brisk walk. These runners understand the importance of not overworking the system in order to be happy with the statistics of the run. All in all, slowing down to run according to “easy” effort or lower heart rate is how a savvy runner allows themselves to adapt to the summer heat.
Hydrate!!
The temptation to celebrate a hot summer run with a cold diet coke or local IPA is what incentivizes many of us to run in the first place. I was once surprised to learn that one of my athletes drank almost exclusively coffee and diet soda throughout the day before hitting the pavement for their post-work run. Evidently a dark yellow urine was not a cause for concern for his running career–yuck! Our resolve wasn’t to eliminate his favorite drinks, but to simply balance out his habits with an appropriate amount of water. Even more importantly, drinking plenty of water after running was key to his recovery. Remember, increased blood plasma volume is the key benefit of heat training, but dehydration often results with that blood plasma thickening. Put simply, no water equals no blood flow and no blood flow equals no recovery. A simple rule you can implement if you prefer diuretic drinks like soda, coffee and alcohol is a 2:1 ratio of water to beverage. Supplement every ounce of your favorite soda with two ounces of additional water intake. Think of it this way: the whole point of summer training is building blood plasma volume, and dehydration does the opposite because it thickens your blood and stalls recovery. Water isn't just a good habit. In the context of heat training, it's the mechanism that makes everything else work.
Whether it is the summer heat, high altitude or uphill running, the key to leveraging the benefits of a change in training climate isn’t about jumping in the deep end with no floaties. If you really want this summer to play into your fall breakthrough, then patiently allowing your body to adapt will prove to be a more effective strategy.
