Right from the first time we picked up a set of dumbbells, we were told and reminded time and time again that cardio is a vital part of training that must be routinely performed conventionally on cardio machines to burn fat and build lean muscle. Treadmills, ellipticals and stationary bikes have become staples for cardio training in commercial gyms. It isn’t unusual to see people run on the treadmill for over an hour! I’m about to tell you why doing that much cardio could be a complete waste of time.

For the majority of us (competitive seasoned runners excluded), we do cardio to burn fat and improve endurance. Our bodies produce fuel via 3 energy systems: the ATP-CP (activities lasting 10-15 seconds), Anaerobic (activities lasting 10 seconds to 2 minutes) and Aerobic (activities lasting longer than 2 minutes) energy systems. All 3 systems are utilized in our daily physical activities. The aerobic and anaerobic systems uses the body’s stored fuels (glucose, glycogen and fat) when we perform steady-state cardio sessions lasting anywhere from 15 to 45 or more minutes and yields a ton of burned fat calories. An average 130-pound person can burn up to 250 calories of fat running on the treadmill at 6 miles per hour.

Great, right?

Well, what if I told you that you could burn more calories in a much shorter amount of time? Recent studies have endorsed High Intensity Interval Training (HIIT) as the most effective cardio method to burn fat. Simply put, HIIT is defined as alternating short bouts of high intensity activities with moderate-to-long bouts of very low intensity recovery periods. An example would be to run at your fastest speed on the treadmill for 30 seconds to 1 minute followed immediately by a slow, mild walk for 90 seconds to 2 minutes. That process would be repeated 6 to 8 times. HIIT has also been associated with increased EPOC (Excess Post-Exercise Oxygen Consumption) in which the body stays in a fat-burning metabolic zone for 24 to 48 hours afterwards!

HIIT can also be performed with traditional exercises like kettlebell swings, clean & press, burpees and squat jumps. Just like the name, it can be quite intense especially if you’re a first-timer so don’t be discouraged if you struggle initially. Due to its taxing nature, HIIT should not be performed no more than twice a week with at least 48 hours apart. Do not perform HIIT if you have a preexisting heart, chronic and/or cardiovascular condition. Always check with your doctor first.