Ribose is a naturally occurring sugar that the body uses to synthesize adenosine triphosphate (ATP). ATP is the immediate source of energy for muscular contraction, and all food energy, such as that derived from fat and carbohydrate, are eventually converted into ATP. Ribose has been used for medical conditions characterized by decreased cellular energy production, such as various types of heart disease. Since ribose appears to be a safe and effective substance, its use has trickled down to the athletic arena, where it is sold as a supplement.
While no one disputes the role ribose plays in ATP synthesis, there is some question as to whether taking supplemental ribose offers any beneficial effect for hard-training athletes. Research hasn’t been able to prove that ribose supplements have a direct ergogenic effect.
Researchers from the Institute of Exercise and Sports Science in Copenhagen, Denmark, tested whether ribose actually does more rapidly replenish ATP stores depleted by intense exercise. Six men participated in a double-blind crossover study, meaning that neither the subjects nor the researchers knew who was taking ribose and who was getting an inactive placebo.
The subjects did a series of high-intensity 10-second sprints on a stationary cycle, with 50-second rest periods. They also took either a placebo or 200 milligrams per kilogram of bodyweight of a ribose supplement dissolved in water. To determine muscle changes in ATP content, the authors took biopsies (bits of muscle tissue) extracted from the subjects’ front thigh muscles before the exercise and at five and 72 hours after training.
The results showed that at the five-hour and 72-hour post-training marks, ATP stores were lower in the placebo group. Those taking the ribose showed lower ATP levels at the five-hour point, but by the 72-hour mark ATP levels were similar to what they were before exercise, indicating a complete replenishment of ATP in the subjects taking the ribose supplement.
The dose of ribose supplied in this study, however, was considerably higher than the usual five to 10 grams suggested for supplemental use. It amounted to about 18 grams for a 200-pound man.
Another study, from a group at Ball State University in Muncie, Indiana, examined whether ribose supplements could effectively replenish adenosine nucleotide (TAN) levels after intense exercise. TAN represents the building blocks of ATP, which are often depleted after intensive exercise. The study consisted of an 11-day supplementation period, during which 16 healthy men, average age 24, took either 20 grams a day of ribose or a placebo.
After taking the ribose or placebo for 72 hours, the men exercised twice a day for five days, for a total of 10 sessions. Each workout lasted 15 minutes and entailed doing high-intensity cycle wind sprints. Muscle biopsies revealed that while both the ribose and the placebo groups lost TAN following the exercise, those taking the ribose lost less. After 65 hours those in the ribose group showed complete replenishment of TAN, while those in the placebo group still showed a 23 percent depletion rate from their starting levels. IM