An exercise machine includes a main shaft having a bottom end and a top end along a longitudinal direction is described. A rotatable element may be provided at the bottom end of the main shaft. A torsion resilient assembly can include a fixed torsion structure, a pivotable structure and an elastic element. The pivotable structure can pivot to deform the elastic element to induce a resilient torque force. An engagement frame may be rotatably mounted to the pivotable structure. User force may cause the rolling of the main shaft to change an angular relationship between the engagement frame and the main shaft to cause the pivotable structure to induce a resilient torque force for user exercising.