“Speed is key—move, walk, or run a little faster and you’ll burn more total calories,” says Kravitz. In fact, changing up your walking pace quickly and frequently can help you melt up to 20% more calories, compared with maintaining a constant speed, according to a 2015 study from The Ohio State University. Try speeding up for 30 seconds, then walking at a comfy pace for three minutes.
The prevailing formula for a long time on how much fat you’re going to burn was calories in minus calories out, based on your basal metabolic rate (BMR) and exercise efforts, explains strength and performance specialist Joel Seedman, Ph.D., owner of Advanced Human Performance in Atlanta. But with all the different biochemical reactions in the body, hormonal response, and endocrine function, there are an infinite number of factors that can affect how your body is storing and breaking down calories.