“Yes! Even in Canada, you must respect running in warm summer weather!”
Discomfort Index – Respect It!
Summer is a wonderful time to get into running or start training for the upcoming Fall marathon season. Needless to say, summer running has added challenge due to heat. Depending on where you live, the combination of temperature and humidity is an even bigger concern. Check out the following “Heat and Discomfort Index”.
In Vancouver today, we are expected to hit 30 degrees inland with a humidity index around 73%. I have a run scheduled for the late afternoon. As usual, I expect to feel quite warm and am now actually wishing I had completed my run early this morning. I’m not worried since I have run in these conditions many times before.
However, according to the chart above, I can expect to experience my run as if it was actually “42” degrees. That is hot! In fact, this temperature and humidity combination places my potential discomfort level at “Strong indisposition sensation. Danger: avoid efforts.”
To Run, or Not To Run
Will this stop me from running today? No way! However, does the chart inform me about the type of workout I should be doing? Yes!
Following is my advice to you when running in the heat. Remember, heat index is a measure of both temperature and humidity (real feel). 30 degrees sounds warm, but nothing like running in 42 degrees when considering temperature and humidity together. Humidity is a killer…literally!
- Slow the F&%K down!
- Be well hydrated prior to your run.
- Stay hydrated during your run.
- Drink before you think you must.
- Avoid hyponatremia; hydrate with an electrolyte mix, not just water.
- Bring an extra hand-held water bottle to drench your head with a couple times on your run.
- Avoid alcohol if you have a hot weather run the following day.
- Avoid alcohol in general!
- Caffeine is your friend, until it causes dehydration.
- Your pee should be straw in colour, not dark, indicating dehydration.
- After your run, hydrate.
- In the heat, run by perceived effort, not pace.
- Get out the door early in the morning, or late in the evening.
- Avoid dark coloured clothing.
Listen To Your Body
Even if you do the above, it is difficult staying hydrated during a training season. One measure I use year round is the dizzy test. One symptom of dehydration is dizziness when standing up from a resting position. This is partly due to lower heart rate and blood pressure, one of the benefits of running, but also intimately related to hydration. Dizziness when standing is a clear indicator that I need to take in fluids and to do a gut check about my sodium and potassium intake.
Runners in general are keenly aware of their physiology. However, regardless of experience, our body throws us curve balls. Be mindful of the heat, and your hydration needs year round, especially in high temperatures and humidity.