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NEWS RELEASE

For immediate release:
May 23, 2002

NEW VITAMIN E STUDY ASSESSES CONTRACTION-INDUCED MUSCLE DAMAGE
Questioned cell-membrane and free radical protection against injury and inflammation

INDIANAPOLIS-The American College of Sports Medicine (ACSM) has released a study that provides more information about the relationship between vitamin E and exercise. The results were published in the May, 2002 issue of Medicine & Science in Sports & Exercise®. It is well known that vitamin E can confer protection against certain kinds of muscle damage, due to its stabilization of cell membranes and protection against free radical formation. radical-induced damage. However, most of the research had concentrated on muscle damage or soreness resulting from aerobic exercise. The present study sought to determine the effect of vitamin E on muscle damage or soreness resulting from contractions, or resistance exercise.

"We knew that vitamin E could limit the extent of vitamin performing some kinds of muscle damage that occur after exercise," said Louise Beaton, McMaster University, lead researcher on the study. "The evidence for contraction-induced muscle damage in humans was not clear, however. We set out to learn the effect of vitamin E supplementation on several indicators of muscle damage, and from that, to conclude whether it has any effect on muscle damage or soreness."

The researchers designed a study that started with 18 20-year-old men. None were taking vitamin E or participating in a resistance training regimen for six months or more. All were nonsmokers. The subjects were divided at random into two groups, and received either a placebo or 1200 IU of vitamin E a day for 30 days before beginning the resistance exercise regimen. After the 30-day period of supplementation, during which the subjects maintained their normal diet, they were instructed to perform a series of eccentric knee extension/flexion contractions in 24 sets of ten repetitions each. The subjects submitted to torque measurement and muscle and blood sampling. Tissue was extracted via needle biopsy 24 hours after the exercise protocol, because contraction-induced injury can be observed at that time, as well as any inflammatory response or muscle band disruption. The blood and tissue samples were subjected to light microscopy, immunohistochemistry and biochemical analysis; subjects were asked to quantify muscle soreness and measured for edema.

The researchers' statistical and chemical analyses indicated that supplementation with vitamin E in humans does not reduce inflammatory cell infiltration, nor does it help muscle function, which is significantly compromised by an exercise protocol like the one designed for the study.

Because of the sample size (only 18 subjects), and due to the fact that only a single muscle biopsy was taken to examine the effects of vitamin E, discussion of the results was restricted, but the researchers believe that supplementation with vitamin E would not confer a protective effect over a longer period of time. In addition, although free radicals play a role in the events after the initial contraction-induced damage, the exact mechanism of how vitamin E mediates this effect remains to be discovered; the researchers therefore recommend further study with a large sample size to adequately address the effect of vitamin E on muscle damage.

The American College of Sports Medicine is the largest sports medicine and exercise science organization in the world. More than 18,000 International, National, and Regional members are dedicated to promoting and integrating scientific research, education and practical applications of sports medicine and exercise science to maintain and enhance physical performance, fitness, health, and quality of life.

NOTE: Medicine & Science in Sports & Exercise® is the official journal of the American College of Sports Medicine, and is available from Lippincott, Williams & Wilkins at 1-800-638-6423. For a complete copy of the research paper (Vol. 34, No. 5, pages 798-805) or to speak with a leading sports medicine expert on the topic, contact the Department of Communications and Public Information at 317-637-9200. Visit ACSM online at www.acsm.org.

The conclusions outlined in this news release are those of the researchers only, and should not be construed as an official statement of the American College of Sports Medicine.