Ask the Diet Doctor: Post-Workout Antioxidants
Q: Is it true that it's important to consume antioxidants after a workout in order to reduce inflammation?
A: No, as counterintuitive as it is, post-workout antioxidants can actually be detrimental to your fitness progress.
Although exercise creates free radicals and increased oxidative stress-so you'd think that taking in antioxidants to quench those free radicals created during your spin class would help get your system back to normal-this isn't the case. The opposite is actually true: Post-workout supplemental antioxidants don't do your body any favors.
You probably appreciate the fact that your body is self-healing and works very well to deal with toxins and stress, building itself back up and coming back stronger than ever. This is the whole premise behind weight training, and your immune system functions via a similar code. Post-workout antioxidants violate that self-healing code and disrupt essential naturally occurring mechanisms designed to deal with exercise-derived free-radical stress. This can hinder your progress in two ways:
1. Muscle growth: The production of free radicals during a workout is needed to stimulate optimal muscle growth. The exact mechanisms in which free radicals help flip the muscle-building switch are unknown, but it seems that free radicals function as anabolic signals to your muscle cells, signaling them to come back bigger and stronger than before. By prematurely quenching these free radicals via antioxidant supplements, you won't be getting the most out of your weight-training sessions.
2. Insulin sensitivity: One of the many great benefits of exercise is that it temporarily improves our muscles' ability to respond to the hormone insulin and take up sugar (i.e. insulin sensitivity), but supplemental antioxidants interfere with this sacred effect. In the scientific paper entitled "Antioxidants Prevent Health-Promoting Effects of Physical Exercise in Humans" (a pretty damning title!), the authors report on a study they conducted looking at the impacts of vitamin C and E, two very common antioxidant supplements, on insulin sensitivity.
The researchers concluded, "Based on the evidence derived from the current study, we here propose an essential role for exercise-induced ROS (reactive oxygen species) formation in promoting insulin sensitivity in humans." The use of supplemental vitamin C and E prevented the necessary formation of free radicals (a.k.a. ROS), and as a result blunted the boost in insulin sensitivity normally experienced following exercise.
In the end, you shouldn't need to supplement with megadoses of antioxidants without a specific purpose if you are making a variety of fruits and vegetables the cornerstone of your diet. The following foods are packed with antioxidants. Frequently eating them removes the need for additional antioxidant supplements:
- apples (especially the skin)
- green tea
- red wine (everyone's favorite)
If you are healthy and exercise on a regular basis, focus on eating these foods throughout the week and maybe even limiting them directly after a workout to maximize the benefits of your exercise while still getting all the antioxidants that your body needs to function at its best.