Gas strut with adjustable resistance

摘要

An exercise machine incorporates a gas strut 1 to be actuated by a user. The resistance to effort needed to actuate the gas strut can be increased by operation of an adjustable piston/cylinder unit 2 so as to compress the gas within the gas strut 1. The adjustable piston/cylinder unit 2 is operated by applying a primary force F to the piston 4 compressing the gas 12 within the cylinder and within the gas strut. The primary force F may be applied either by using a threaded bolt arrangement (see figure 2), using a ratchet mechanism or by using a hydraulic system.