D-Ribose sparks the generation of Adenosine Triphosphate (ATP) the primary energy source of muscle tissue, and essential in high levels for high intensity training such as weight training.
Creatine is used by the body to rapidly regenerate ATP during exercise - in seconds - whereas D-Ribose plays a part in actually creating ATP in preparation for training. They can be used synergistically for enhanced effectiveness.
Take 5g per day mixed in water. 5g is around 1 rounded teaspoonful.