Dear Dr. Bell, I have been working out for several years and have a good deal of experience. The last few weeks, I have been feeling faint and dizzy at the end of my workouts. Today, I went to “push-it” for the last 3 reps and I had to stop. I tried lowering the weights to drop the intensity, but it still happened again (but to a lesser degree). Do you have any thoughts, pointers, or checks I can to do to figure out what’s going on?
I am going to have to make a few assumptions since you did not provide much detail. Assuming you are working out in an air conditioned gym so the summer heat, humidity and hydration are not the cause of your dizziness, and you have not changed your sleeping patterns, medications or stress level, I immediately suspect it is your nutrition.
Though you say you have been working out for several years, I have experience with many bodybuilders who have experienced fainting and dizziness when they cycle to a low carbohydrate diet. Low carb diets may help you “Cut-Up” your musculature, but low carb definitely impacts your performance.
Carbohydrate is to your body; what gas is to your car. While protein and fat can act as an energy source, they are inefficient sources compared to carbs for Anaerobic Activities such as weight-lifting. To avoid fainting in the gym, increase your carbs or decease your workout Frequency, Intensity, Time (duration) and/or Type.