Your Health by Dr. Rallie McAllister

The best performance-enhancing beverages for seasoned athletes and weekend warriors may not be sports drinks, after all. If you're willing to experiment, you may find that you're able to exercise longer and recover more quickly after downing a glass of beetroot juice or even a cup of coffee.

The results of a study published in the Journal of Applied Physiology showed that drinking beetroot juice prior to working out boosted stamina in male subjects and enabled them to exercise longer.

The men enrolled in the study were given 500 milliliters (slightly less than 17 ounces) of organic beetroot juice for six consecutive days before completing a series of cycling tests. For comparison, the men were given a placebo drink of blackcurrant juice for six consecutive days prior to engaging in the same series of cycling tests on a separate occasion.

Scientists from the University of Exeter and Peninsula Medical School found that when the men performed the cycling tests after consuming the beetroot juice, they were able to exercise up to 16 percent longer than after they had consumed the blackcurrant beverage.

The researchers demonstrated that drinking beetroot juice reduces oxygen uptake in exercising individuals to an extent that cannot be achieved by any other known means, including physical training. When the body's oxygen demands are reduced, exercise is less tiring for the individual.

While the exact mechanism by which beetroot juice boosts stamina isn't fully understood, it is believed to be linked to nitrate, a chemical compound found in high concentrations in beetroots. In the body, nitrate is converted to nitric oxide, a compound that appears to significantly reduce the oxygen cost of exercising.

If you're not crazy about the idea of drinking beetroot juice before working out, you might opt for a strong cup of coffee instead. Last month, researchers at Coventry University in England reported that high doses of caffeine can significantly increase muscle power and endurance during sub-maximal exercise.

Maximal exercise, which involves working the muscles at full capacity, is required in activities such as sprinting or heavy weight lifting. Most other activities, ranging from mowing the lawn to jogging around the block, involve sub-maximal exercise.

Scientists have long known that caffeine consumption can enhance athletic performance by stimulating the central nervous system.

The results of the new study suggest that very high blood levels of caffeine also may act directly on muscle tissue to increase muscle power.

While high doses of caffeine may effectively enhance exercise performance, less is needed to reduce muscle soreness following workouts. In a study conducted at the University of Georgia, researchers found that moderate doses of caffeine, equivalent to the amount in two cups of brewed coffee, reduced post-workout muscle pain by up to 48 percent in exercising volunteers.

Caffeine appears to reduce exercise-related muscle soreness by blocking the body's receptors for adenosine, a chemical messenger released in response to tissue damage and inflammation. Based on their research, the scientists concluded that caffeine is significantly more effective in relieving post-workout muscle pain than some over-the-counter pain relievers, including aspirin and naproxen.

Drinking a caffeinated beverage before exercising may help improve athletic performance and alleviate the resulting muscle aches, but there's a good chance that it also might interfere with sleep, which is critical to muscle recovery. In addition to contributing to sleep disturbances, too much caffeine can produce jitteriness, irritability and heart palpitations in some individuals.

If you're sensitive to the effects of caffeine, cherry juice might be a better choice. Natural compounds in cherries can help reduce muscle pain and damage induced by exercise, according to the results of a study published in the British Journal of Sports Medicine.

Researchers at the University of Vermont found that when subjects drank cherry juice before and after performing strenuous arm exercises, they experienced significantly less pain following their workouts compared to when they drank a placebo beverage that contained no cherry juice.

When the men drank cherry juice before and after exercising, post-workout pain peaked at 24 hours and then began to subside. When the men drank the placebo beverage and performed identical exercises with the other arm, the pain continued to increase for 48 hours before subsiding.

Whether you're eager to take your athletic performance to the next level or you just want to make exercising a little easier and less painful, drinking coffee, beetroot juice or cherry juice before your workouts might help you accomplish your goal.

Rallie McAllister, M.D., is a family physician, speaker and co-founder of www.MommyMDGuides.com, a website featuring child-raising tips from trusted doctors who are also moms. To find out more about Rallie McAllister, M.D., and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate Web page at www.creators.com.

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