to lose 1 pound you need to burn 3500 calories. But the calories you burn during any particular exercise session are only part of the equation. the intensity of your exercise sessions can keep you burning extra calories long after you have finished the workout. This afterburn can be the key to efficient weight loss.
The answer in a test tube is 3500. The confusion in reality is that we don’t know how each individual reacts to exercise after eating and during different activities, so it is impossible to calculate without measuring expired gasses during daily activities and exercise (too complicated, too many variables). Heart rate does not tell you what type of calories you are burning, but that doesn’t mean you cant use a monitor to your advantage. Most importantly, you should be thinking about the exact effects that each bout of exercise has on your hormone system and metabolism over the remainder of the day, not just calories per bout of exercise. Find the book Modern Nutrition in Health and Disease by Goodhart and Shils. See page 29! This is where it gets interesting- If I take a diuretic and lose a lb of weight, did I burn a lb of fat? If a women is on Prednisone or hormone Replacement Therapy (yes this is common) and you put them on a calorie restriction diet will they lose a lb of fat? Ever? Great question for debate and who cares what cardio machines say? Do people still use those things…
Yep, the text book answer is (c) 3500 calories. As stated before, counting calories is an “approximation” at best. One reason that I focus on body fat reduction and how clothes are fitting is to try to take some of the guess work, and required hyper-vigilance of counting calories out of the whole equation. I want my clients to focus on the end results, the forest if you will, instead of the day-to-day, and very tedious job of calorie counting.
Perhaps a more effective way to adress your question is to recognize that losing weight is based on energy balance, calories in versus calories out. The evidence suggests that a negative energy balance of approximately 3,500 kilocalories will lead to a weight loss of a pound. This simply means that we need to expend 3,500 more kilocalories than we consume in order to lose a pound.
That’s why I encourage clients to keep a detailed 3-day dietary record to determine if there may be ways to eliminate unnecessary caloric intake. But keep in mind that adequate intake is essential in order to give the body adequate energy reserves to support the vigorous exercise that is the key to effective weight loss and long-term weight management.