An air management system that allows safe and convenient forms of interval training exercise to be performed on pneumatically elevating rebound exercise equipment. The system includes at least one air intake valve and bleed valve. By providing repeatable degrees of difficulty for both air intake and air release from the extendable air springs employed for the exercise, competitive athletes and their coaches can design, employ, repeat, and compare individualized medium- or high-intensity interval protocols for optimal cardiovascular training programs.