In this study, thirty-two men completed eight weeks of aerobic exercise training after completing tests for maximal aerobic capacity as well as time to exhaustion at 90% VO2Max in addition to having their percent body fat and fat-free mass determined. The test drink provided a balanced combination of carbohydrates (76 grams), protein (14 grams) and ribose (2.2 grams) which was compared against a group that consumed only carbohydrate (93 grams).
Delivering optimal amounts of carbohydrate is critically important as it is the primary source of fuel for nearly every exercise effort that requires maximal effort. More so, stores of carbohydrate are limited and when athletes perform intense bouts of exercise, carbohydrate stores can be depleted at an accelerated rate. A healthy dose of protein is important to facilitate absorption and delivery of the essential amino acids which helps to ensure rates of muscle protein synthesis are maximally activated and can also aid the muscles in recovering from stressful exercise. The inclusion of ribose is somewhat surprising as study outcomes relating exercise performance and ribose have been somewhat mixed, but very few studies have examined the impact of including ribose with other key ingredients such as carbohydrates and protein.
All subjects in this study exercised five days per week at approximately 70% VO2Max for one hour at a time over the eight week study period. Immediately after each workout, participants were required to ingest a single dose of either the carbohydrate placebo drink or the drink containing carbohydrate, protein and ribose. All study participants had their body weight and body composition determined at the beginning, the middle and end of the study period in addition to completing several tests of aerobic exercise performance. The authors reported that favorable decreases in percent body fat from the beginning to the middle of the study were greater in the group which consumed the combination of carbohydrate, protein and ribose when compared to the changes seen in the carbohydrate only group. Additionally, improvements in fat-free mass were reported to be greater in the carbohydrate, protein and ribose group from the beginning to the middle as well as to the end of the study period when compared to the carbohydrate only group. The authors concluded that even though the supplement group did very little to augment changes in exercise performance variables such as time to exhaustion and attainment of VO2Peak, the daily administration of a combination of carbohydrate, protein and ribose did seem to favorably impact changes in percent body fat as well as fat-free mass. Considering the most favorable outcomes were closely related to favorable changes in body composition, a key unknown question remains what might happen if the influence of resistance exercise was included as part of the regular exercise training program.
Cramer, J. T., T. J. Housh, et al. (2012). "Effects of a carbohydrate-, protein-, and ribose-containing repletion drink during 8 weeks of endurance training on aerobic capacity, endurance performance, and body composition." J Strength Cond Res 26(8): 2234-2242.