while high-intensity interval training (HIIT) is an effective way to build your cardio base, and has been shown to improve VO2 max and peak anaerobic power output, there is still a strong argument for including traditional steady-state cardio like running, swimming, biking, rowing, and the elliptical machine into your workout. It’s good for variety, for laying the foundation for greater endurance, and for those beginning training or coming back after a long layoff.
