An improved wheelchair trainer with independent flywheel resistance for each wheelchair rear wheel. A lever-operated cam raises the wheelchair rear axle by pushing an inclined block against the axle and forces the rear wheels against wheel engagement means. As one or both rear wheels are turned, each wheel engagement means turns a flywheel in proportion to the speed of the wheel. Force and work may be calculated from the measured rotational speed of the flywheels. A hand-cycle attachment may drive the flywheel resistance.