Complementary Prescriptions' D-ribose is a key player in synthesis and regeneration of ATP (adenosine tri-phosphate). D-ribose appears to have an important clinical role in cardiac health, specifically related to myocardial contraction during times of acute depletion and increased demand for ATP. Athletes report improved speed and recovery following intense exercise. D-ribose may also help conditions of chronic fatigue, muscle tenderness, joint sensitivity and lethargy.