Done consistently, both running and walking are excellent cardio workouts to burn fat [1] and lose weight. Combining either one with HIIT-style intervals? Even better, said Tom Holland [2], MS, NSCA-CSCS, an exercise physiologist and author of The Marathon Method. Interspersing your run or walk with sprint or fast walking intervals followed by slower recovery periods will "elevate your heart rate for short yet manageable durations, increasing the calories burned from fat," Tom told POPSUGAR.

If you're short on time, Tom recommended a simple 30-minute interval circuit to rev up your fat burn and help you work up a sweat. You don't need a gym or any equipment; start with some dynamic warmup stretches [3], then lace up your shoes and head out the door.

30-Minute Interval Workout For Running or Walking

Here's what to do:

• Walk or jog at a slow, easy pace for 10 minutes to warm up.
• Power walk or run hard for one minute.
• Walk or jog at a slow pace for one minute to recover.
• Repeat for a total of 5 intervals (10 minutes in all).
• Slow down to a slower walk or jog for 10 minutes to cool down.

After your run, supplement the cooldown with full-body stretches [4] to promote recovery (and help you walk down stairs the next day.)

Quick, simple, effective: this is a great interval workout to work up a sweat anywhere, anytime, burn fat, and even help you get faster [5], if you're a runner. See you on the sidewalks! (Rather run on the treadmill? Try this 30-minute interval workout [6] the next time you're at the gym.)