Abstract: An exercise apparatus for high intensity interval training includes a pair of elastomer tubing devices being stretchable beyond a resting length and further having a first end forming a hand grip for a user, and an opposing end including an anchor portion to enable releasable attachment to a fixed mount. The elastomer tubing devices are independently affixable to one or more fixed mounts at a first distance between the respective anchor portions along a transverse plane and a second distance above ground level to permit independent or tandem oscillation by the user, wherein the elastomer tubing devices are stretched a predetermined distance beyond the resting length and maintained approximately at the predetermined distance during the oscillation. Mechanical impedance of the elastomer tubing devices is adjustable by the user working against inertia generated during the oscillation.