Provided is a four stroke internal combustion engine comprising at least one cylinder arrangement, a crankshaft, a camshaft, and a turbine. The camshaft is synchronized with the crankshaft to rotate at a same rotational speed as the crankshaft. A linkage arrangement is configured to prevent the motion of the valve head every alternate rotation of the camshaft, such that the exhaust opening remains closed during a compression stroke of the piston. Also a method for controlling a four stroke internal combustion engine is disclosed.