An auxiliary structure to improve efficacy of a fitness equipment includes a pair of swing bars pivoted to a pair of traction bars wherein in turn pivoted to a crank; the crank drives a sprocket and a resistance control wheel for both swing bars to drive both traction bars to travel up, down, back and forth; each pedal is disposed with a roller to travel in a slide attached to the traction bar and is pivoted to a pull-and-push connection bar, which in turn is pivoted to a transmission connection bar; each transmission connection bar is pivoted to a support; each mid section of the transmission connection bar is pivoted to an active connection bar, which in turn is pivoted to the swing bar; and each pedal is dragged by the push-and-pull connection bar driven by the transmission connection bar when both swing bars alternatively swing to drive the transmission connecting bar to increase longitudinal travel ranges of both pedals for providing adequate exercise amount for waist and legs of a user to improve exercise efficacy.