Exercising in the heat is a challenge for any athlete. Whether you’re running a road race, training for your next triathlon, or just want to get out and exercise, these summer exercise tips will keep you going strong even when temperatures rise. The generally accepted “ideal” temperature for running is 55-60 degree F. So anything above 60 degrees can be considered “running in the heat”!
What happens when I run in high heat and/or humidity?
To boil it down without getting too eggheady, as your core temperature increases several things happen. First, as the humidity increases (above 70%…a Knoxville summer day is apt to be 90%+ humidity), the sweat will no longer evaporate efficiently (the surrounding air already is laden with moisture and can’t take up much more). Sweating cools the body by first heating the sweat and then removing that heat through evaporation. With this inability to cool the body a cascade of physiological events occur starting with an increase in core temperature. As your core temperature increases muscle activity and efficiency decrease, thus requiring greater effort, further elevating your core temperature. Additionally, at this point various muscles will shift to anaerobic functioning, directly sapping your muscles of energy. As a high core temperature is maintained the body will continue to direct blood flow to the extremities and the body’s surface where the blood vessels are closer to the skin in an attempt to cool the body down. This means there is a lack of blood volume being pumped by the heart, which further reduces oxygen being delivered to muscles, which leads to a continued decrease in performance.
So…what should you do?
Get Used to the Heat
Doing your normal exercise routine on a hot day is fine — if you’ve taken the time to get used to the heat.
Try to spend at least a week getting up to speed, starting with short intervals (10-15 minutes) and working up. Even after you’re acclimatized, which takes about 7-10 days, you may consider doing part of your workout indoors and part out, especially if you’re prone to overheating.
And know when to say when. It’s the number of days you exercise, not how long — even a 20-minute workout has health benefits. If you’re feeling any of these symptoms you need to slow down and cool off!
- Dizziness
- Weakness
- Light-headedness
- Abnormally rapid heartbeat
- Paling skin
- Headache
- Nausea or vomiting
- Muscle cramps
Slow Your Roll
While you may know you’re in shape to run, bike or swim a race, who says the weather agrees? As Dane Rauschenberg of Runner’s World says, choosing a slower pace overall means not collapsing at the finish. You may not hit your best time, but you probably won’t need the ambulance, either.
By the way, the general rule of thumb is that your pace should slow about 15-30 seconds per mile for every 10 degrees above 60 degrees. If you are wondering why you can’t maintain your 8:00/mile pace at 90 degrees….it’s NORMAL! As your fitness level increases you’ll be able to minimize this rule, especially for shorter races – but nobody is immune to the effects of heat and humidity. This is one reason why wearing a heart rate monitor and doing Zone Training is a better way to train as it uses your effort to gauge training rather than time, pace, or distance.
Electrolytes?
What in the world are electrolytes anyway? They’re minerals like sodium, potassium, magnesium, and calcium that are critical for all cellular functions. They also maintain the body’s fluid balance, replenishing the body’s water and electrolyte levels after exercised-induced dehydration.
Runneracademy.com notes that when you consume fluids is just as important as how much. If you’re exercising under 90 minutes, your body has enough electrolytes stored that there’s no benefit to consuming more. Water alone is enough and you should drink 4-6 oz every 20 minutes for an 8:00 minute mile pace. If you’re running faster than that you should up it to 6-8 oz every 20 minutes. And don’t forget to PREHYDRATE for a couple hours before a long run (even the night before)!
Exercising for more than 90 minutes? That’s when supplementing electrolytes becomes vital for optimum performance. That may mean adding a sports drink or a carb like a piece of fruit.
The more fit you are, the more efficiently your body uses electrolytes, so everyone’s need will be different. If you’re experiencing any of these, you may be low on electrolytes:
- Frequent leg cramps
- Side stiches
- Stomach cramps
Take It Inside
Summer’s a great time to mix it up. Since running long distances outdoors is tough, do your speed training on an indoor track. Swimming gives your overtaxed muscles and joints a break and is especially good if you’re recovering from injury. Cycling is another way to give your body a break from the high impact of running, developing the quads and shins and strengthening the connective tissues in knees, hips and ankles.
Once the temperatures drop, and the days get shorter, you’ll need the daylight to keep SADD at bay. So enjoy that air conditioning while you’ve got it.
