Fitness and weight loss “experts” like to recommend finding ways to incorporate more physical activity into daily life, usually exchanging efficiency or convenience for increased physical exertion, based on the mistaken belief that doing so makes a meaningful contribution to health, fitness, or fat loss. They claim these little changes add up to a lot of calories burned over the course of a week, however this is not the case. If hour-long “cardio” sessions barely burn enough calories to be worth doing for that purpose, a few minutes walking up the stairs or across a parking lot are hardly going to amount to any calories burned, while reducing your time and productivity.
Unless you enjoy these activities for their own sake, doing them to burn calories is not worth your time. You could accomplish as much of negative calorie balancein a single day with a few dietary changes as the typical recommendations for increases in activity would amount to over several weeks, without it costing a minute of your time.
In a recent post I mentioned a study from the 2009 European Congress on Obesity (Swinburn BA, et al “Increased energy intake alone virtually explains all the increase in body weight in the United States from 1970s to the 2000s” ECO 2009.) which showed a lack of activity is not the problem. Overeating is. If you want to lose fat, forget about spending a few extra minutes walking an extra block to work; you’ll barely burn the amount of calories contained in a few french fries. Instead, save yourself a few minutes and skip the french fries to begin with.
The following are just a few suggestions for dietary improvements that will make a much bigger difference in fat loss than adding a few minutes of extra activity throughout your day:
- Substitute a variety of fresh vegetables and fruits, especially leafy vegetables and berries for more calorie dense grains and starches.
- Choose moderately leaner sources of protein – certain fats (animal fats, butter, egg, coconut oil, etc.) are healthy but very calorie dense.
- Substitute water or other non-caloric beverages like tea for sodas and fruit juices.
This is not to say I believe people should be inactive. There are other benefits to getting up and moving around. However, doing so makes little or no positive difference in body composition.
The only worthwhile exercise for improving body composition is strength training. High intensity strength training in particular provides the greatest physical benefits relative to the time invested, including all of the cardiovascular and metabolic benefits of aerobics or “cardio”. Strength training directly improves body composition by increasing muscle mass and by preventing loss of muscle mass while fat is lost in people restricting calorie intake, and indirectly because more muscle mass equals a higher basal metabolic rate and more storage space for glucose (as glycogen). High intensity strength training also depletes muscle glycogen levels, so more of the carbohydrate consumed is stored as glycogen in the muscles than as triglycerides in the fat cells.
So, if you’re in a hurry to get to work or have better things to do with your time, go ahead and take the elevator or park in the closest spot – you’re not missing out on any kind of major calorie-burning or conditioning benefits. If you need to lose fat, focus on improving your diet instead.