If the limits of performance in human powered vehicles (HPV) are to be reached, designers of HPVs need to understand how the body interacts with the vehicle to maximize propulsive forces, and how the vehicle interacts with the environment to minimize resistive forces. This paper will review, compare and summarize the various research literature on both upright and recumbent cycling positions regarding how systematic changes in external mechanical variables (seat-tube-angle, seat-to-pedal distance, crank arm length) interact with internal biomechanical factors (hip, knee, and ankle angles) to affect power production and cycling performance. Conclusions for future research will also be also presented
