Summer Exercise Safety Part 1: Nutrition and Hydration

Summer is a great time of year for exercise.  The sun is up for longer so we have more opportunity to get out and exercise during the light hours.  However, with the sun come the heat and the humidity.  This dynamic duo can be a one-two punch to an otherwise good intentioned healthy program.Although it is always important to maintain sound dietary and fluid intake, the risk of dehydration and malnutrition are more worrisome and potentially deadly in the summer heat.

We lose more electrolytes as our perspiration volume increases in the summer months.  For instance, a 30 minute run in the winter that may barely break a sweat can produce a sweat bath and squishy shoes during the dead heat of summer.  In this heat you may need to stop more often to hydrate or carry hydration bottles on you to drink as you go.  Remember, though, over hydration can also be dangerous.  A good rule of thumb is that if you sweat more, you will need to replace more.  You should plan to start hydrating before you exercise.  During higher intensity activity and warmer climates, estimate 5 to 7 ml per hour of water or sports beverage per kg. of body weight (about a half liter or 16 ounces for a 150 pound person per hour).Drink when thirsty and do not over drink.  This may not apply to all sports or activity levels but it is a rough estimate of the fluid needed to replace that lost with excessive perspiration especially with high intensity sports.  I had the grand luck a couple of weeks ago to hike in Yosemite Valley.  On one particular hike I happened to carry a 3 liter pack of water.  Normally that would have been about half full upon return.  This time it was so hot on the hike that I had to share with others on the hike.  The water disappeared before I finished.  Whatever you do, plan ahead so you will have enough water stops or enough water on you (or appropriate water purification methods) so you don’t get dehydrated.

Replacing and maintaining your spent or lost fuel and nutrients are also equally important.  Getting the right nutrition for your body helps you get through the exercise and is of utmost importance in the recovery phase.  There are many quick nutrition bars, gels, squares, etc. that are lightweight and tasty.  These can act as a great portable refueling option for a longer run, bike ride or hike when you are too far out to carry your yeti.  On a long hike I will always stuff some trail mix, a couple of nutrition bars and a few gel square packs into my hydration pack to get me through.  Bring lunch if it is long enough.  On a run or bike ride the gels can give a much needed boost if your taste buds are used to them.  Try them out on a non race day so you know what to expect when you squirt them in your mouth.

When the exercise is over, don’t forget to restock lost fluid and nutrients.  Don’t wait too long in the day to eat.  You will recover much faster if you quench the fire.  After a long run I have found great reward in what my family now calls a “Pete’s world famous”.  This is a smoothie using the following:

  • One banana,
  • One yogurt ( I use strawberry but taste can dictate; Also, I prefer Greek),
  • 8 frozen strawberries (instead of ice),
  • One scoop of protein mix (or a scoop of dried milk) to thicken the shake
  • About a cup of milk (liquid amount adjusted to texture).I have recently substituted one chocolate ensure for the milk but I have had some flak from my critics about the combination of tastes.  I personally like it.

There is a bounty of refueling options and there are people who specialize in exercise nutrition who can help with these topics.  Remember: don’t let the heat ruin your good intentioned exercise. Hydrate appropriately and refuel.