Modular heavy bag with spindle support

A heavy bag for boxing, martial arts, or other athletic practice, generally cylindrical in nature having a bottom, a cylindrical vertical side wall, and an open upper end subject with closure, there being positioned within the shell, a disk member adjacent the bottom of the heavy bag, the disk member having an upwardly extending step spindle, the step spindle extending upwardly proximate the open end of the bag, there being slidably receivable on the step spindle a plurality of modular toroidal drums or cells whose central aperture is complimentary with the diameter of the particular step spindle and its outer circumference is complimentary with the internal diameter of the cylindrical shell side wall of the heavy bag, there being positioned between each of the modular toroidal drums or cells on the step spindle, a washer or disk member supported on a respective step of the spindle and providing support to the adjacent upper modular toroidal drum or cell so as to prevent compression of the lower drum and thereby contribute to a heavy bag which maintains its proper density and resilience and resistance over the height of the bag through usage and time, each drum being filled with suitable stuffing or filler.