US Patent 11465005 Manually powered treadmill

A treadmill includes a frame; a rotatable element coupled to the frame; a running belt at least partially supported by the rotatable element; and, a first element and a second element, both of which are coupled to the running belt. The running belt includes a running surface, at least a portion of which is curved. Further, one of the first and second elements and the running belt freely rotate in a first direction of rotation relative to the frame. However, in a second direction of rotation, opposite the first direction of rotation, the one of the first and second elements is substantially prevented from rotation relative to the frame to substantially prevent or resist rotation of the running belt relative to the frame.