Eat To Grow: E Is for Exercisers

Studies have shown that taking vitamin E ensures the integrity of muscle cell membranes. The cell membranes contain large amounts of polyunsaturated fat, which is highly vulnerable to oxidation. Since aerobic exercise involves an accelerated intake of oxygen, it’s not hard to understand how increased oxidation of cellular membranes can occur. Vitamin E is an antioxidant that’s especially effective at protecting the fatty portions of cell membranes from oxidative damage.

What many people often overlook is that weight training also causes increased oxidative reactions in muscle cell membranes. As long as you breathe while training, you’re subject to increased cellular oxidation. Not breathing may forestall the process, but it leads to other problems. Since vitamin E protects muscle cell membranes during aerobics, it stands to reason that the nutrient should also work during weight training.

A researcher from Ball State University in Indiana recently confirmed that theory. The study involved 11 untrained men, average age 25, who lifted weights for three weeks. Six of them took a daily supplement of 1,200 international units of vitamin E, while the other five took a placebo. The researchers verified muscle damage by measuring creatine kinase, an enzyme found in muscle that’s not only a key player in creatine metabolism but is also released in greater quantities following muscle damage. The subjects’ creatine kinase levels were measured after they did three sets of upper- and lower-body exercises.

The results showed that in the men taking the vitamin E supplement, creatine kinase levels rose within 48 hours after training. In those taking the placebo, the creatine kinase levels peaked at six and 24 hours, thus indicating more extensive muscular damage.

The vitamin E didn’t affect either power or force production, though it did appear to increase insulin sensitivity.

Extensive research on vitamin E shows that effective dosages that bring added health benefits’such as increased antioxidant activity’begin at 400 units a day. While it’s not difficult to obtain the recommended minimum dose of 15 units, it’s impossible to get those effective amounts of vitamin E from food alone. Since vitamin E is also a fat-soluble nutrient, it should be taken with some form of fat.

You should also increase your vitamin E intake if you use any type of polyunsaturated fat supplement, such as fish or flaxseed oil. The best type of vitamin E supplement contains mixed-tocopherols, the scientific name for the vitamin E complex, although most products list only the alpha-tocopherol content, since research has shown that it’s the most active form of the nutrient. IM