Weighing in on Hydration
Proper hydration is not only critical for peak performance, it’s also an important health consideration—especially in these sweaty days of summer. Indeed, sweat losses of 1-2% of body weight can compromise performance, while losses of 4% or more can result in a trip to the hospital.
“Being aware of how much you typically sweat in long runs versus short runs, threshold/race pace runs versus long slow runs, and in hot humid weather versus cooler weather is important in helping set up your fluid plan,” says sport dietitian and exercise physiologist Beth Mansfield.
This fluid plan will ensure that you meet your fluid needs without dipping into excessive levels of dehydration. To plan this fluid strategy, start with weighing in before and after different types of training in different conditions. Your strategy is to minimize those sweat losses at the end of your training session to 1-2% of total body weight. If you’ve sweated off more than this you will need to increase your typical fluid intake for that type of training session. Every kilogram of body weight (2.2 lbs.) lost during exercise, on top of any one fluid you have taken in, is the equivalent of about 1 litre of fluid.
However, it’s also important not to overhydrate, which can cause a serious condition of low-sodium levels called Hyponatremia. Put your hydration plan into practice during training to ensure that once race time comes – you will be fueled up, hydrated and running your best!
For more information about dehydration and hyponatremia, check out Beth’s blog.