A recent study found that even in healthy people, foods that are high in sodium will immediately hinder your bodys ability to widen arteries and in turn deliver oxygen to your muscles, or vasodilation. The study, which was published in this months The American Journal of Clinical Nutrition, found that salt somehow inhibits nitric oxide from widening the arteries, but the hardened arteries relaxed within 2-3 hours. The long-term effect of this is specifically unknown, but everyone knows that diets high in sodium lead to heart disease and high blood pressure.
This is, of course, important to gym bunnies because it means that if you eat foods that are high in sodium before working out, your body will be unable to deliver the blood and oxygen necessary to get a good pump and build muscle.
Moral of the story: Don’t eat foods high in sodium, but especially don’t eat them shortly before workouts!