Why do I feel so tired after workouts?

April 30th, 2012

Almost everyone has heard about the importance of hydration.  What I am finding in my practice, however, is the lack of awareness of how to properly hydrate.  While this may sound trivial, the issue can be quite serious.  When you sweat, you not only lose water but you also lose significant amounts of sodium and potassium.  In our bodies, salt is what holds onto water;  think of all the times you have salty food and feel bloated afterward.  By replenishing the body only with water, you don’t significantly rehydrate as most of the water passes into the urine.   Thus, having low levels sodium and potassium can cause low blood pressure, fatigue and weakness. I advise my patients to drink Gatorade or Powerade to replenish the salt lost.  This is extremely important when exercising in hot weather.    

If you have high blood pressure or kidney problems, be careful not to drink too much sports drinks as the salt load can worsen these conditions.  For the same reason, sports drinks should not be consumed if you are not exerting yourself (e.g. sitting on the couch watching TV).  Sports drinks are also helpful for people with diarrhea to rehydrate.