5 hours of cardio in 90 minutes!

Maybe you don't exactly look forward to cardio day, but you want the cardiovascular conditioning and weight management benefits that running, cycling and swimming offer.

A study published in the Journal of Physiology suggests that you can get the equivalent benefits 5 hours of steady state running provide in just 90 minutes using a combination of High Intensity Interval Training (HIIT) and Sprint Interval Training (SIT).
SIT is performed on a stationary bike by sprinting all-out for 30 seconds followed by 4½ minutes of slow paced active recovery. A good starting point is 4 to 6 sets.

You can use the same stationary bike to perform HIIT which typically involves 15 to 60 second bursts of power followed by 2 to 4 minutes of low-intensity pedaling. Researchers suggest that 3 sessions of SIT and/or HIIT totaling 90 minutes per week provides the same quality of training you'd get with 5 hours of steady state cardio. Mix it up and move between these variations on different weeks.