We place in this category, the bikes designed for the larger than 1m75. (Size X or XL) The length of the cranks is adjusted to smaller sizes. This point is very important to allow good recovery : the crank is shorter, the knee goes up less high and the venous return can be done naturally at the level of the popliteal fossa. As the blood circulates more freely, the heart less tired and the blood gets more oxygen.
The height of the bottom bracket is also lowered so you don't sit too high relative to the earth (such as the crank is shorter we can have a bottom bracket lower without fear that the pedal touches the ground in a turn).
The height of the frame is 50 or 58 cm.