An engine braking method includes the steps of engaging a cam roller(235) of an internal combustion engine with an engine power cam(230) for an engine power operation; disengaging the cam roller(235) from the engine power cam(230); losing a motion from the engine power cam(230) and a motion of an engine valve(301) associated with the motion from the engine power cam(230); engaging the cam roller(235) with an engine braking cam(2302) for an engine braking operation; transmitting a motion from the engine braking cam(2302) to the engine valve(301); and generating an engine valve motion for the engine braking operation. An engine braking system includes an engine power cam(230) of an internal combustion engine; an engine braking cam(2302) of the internal combustion engine; and a cam roller(235) that is designed to engage with the engine power cam(230) for an engine power operation and to engage with the engine braking cam(2302) for an engine braking operation.