Torsion adjusting method of arm body-builder and torsion adjustable arm body-builder

The invention discloses a torsion adjusting method of an arm body-builder and a torsion adjustable arm body-builder, which belong to the field of body-building instruments. The arm body-builder comprises a mandrel, and is characterized in that holding wheels are arranged at two ends of the mandrel; more than one worm spring is arranged inside the holding wheels; the inner ends of the worm springs are coupled with the mandrel; the outer ends of the worm springs are coupled with a control mechanism; when the torsion is increased, the outer ends of the worm springs are relatively fixed with the holding wheels through the control mechanism; and when the torsion is reduced, the outer ends of the worm springs are in a free state through the control mechanism. The torsion of the body-builder can be adjusted by flexibly increasing or reducing the number of the worm springs in the working state, and a body builder can do exercise in a gradual mode.