Will I still lose weight if I exercise but still eat whatever I want

Food, glorious food. If only there was some way to eat all you wanted without having to worry about that pesky, life-threatening, profile-altering fat. But with all the attention that is focused on the important role exercise plays in weight loss, surely there must be a way to exercise like mad and still eat whatever you want. The short response to such a proposition is "Nope." That is, unless you happen to just want to eat modest amounts of healthy, low-calorie foods.

Exercise assists with weight loss but it can't compensate for poor food choices. (Image: MitaStockImages/iStock/Getty Images)

The Basic Formula

Weight loss is a matter of calories in, calories out. So long as you expend more calories in your daily activities than you take in eating, you can lose weight. To lose one pound of weight, you must burn 3,500 calories by increasing the calories you burn in your activity, reducing how much many calories you eat or some combination of the two.

Daily Caloric Needs

Even if you are completely sedentary, you burn a certain number of calories operating your brain and body. This is called your basal metabolic rate, or BMR. The more you weigh, but more calories you burn because it takes more energy to maintain your larger mass. Your respiratory, circulatory, cardiac and other body systems have to work harder because there is more territory to cover, so to speak. A 40 year-old, 180-pound male who is 5 ft. 8 in. tall needs 1,779 calories to maintain his weight, estimates BMI-calculator.net. A man of the same age and height needs 2,090 calories to maintain his weight. Any calories you consume beyond your BMR must be burned off in activity. If you want to lose 1 lb. a week, the amount recommended by many health experts, you must burn at least 500 calories per day more than you ingest.

Best Weight Loss Exercise

Exercise does play an important role in weight loss and weight maintenance. The most effective way to burn calories is cardio exercise, also called aerobic exercise. Cardio exercise involves the repeated exertion of your lower body muscles. These are the largest, strongest muscles in your body, so they require more fuel to operate. Health and fitness experts recommend you do moderately intense cardio exercise like brisk walking, swimming or cycling for at least 30 minutes a day at least five days a week. You could also try circuit or interval training; two different methods that will let you burn more calories, faster. If you weigh 185 pounds and you do 60 minutes of moderately intense cardio exercise, such as running at 6 mph, you burn 888 calories. If you attain the fitness level where you can maintain that pace longer and you have the time to put into it, you could perhaps double the calories you burn up to 1,800 or so. However, if you could do this, that would make you an extraordinary person as few non-athletes expend that many calories in exercise.

Limits of Exercise for Weight Loss

Now consider the other half of the formula: calories in. While the calories you can reasonably burn in exercise has a definite limit, the calories you can consume is virtually unlimited. A triple Whopper with cheese, large fries and large soda will give your over 2,000 calories, more than enough to reload all those fat stores you emptied during your arduous two-hour run. And that's just lunch. If you decide to eat a couple of slices of sausage, deep-dish pizza for dinner, you've just added more than 1,500 additional calories to your daily intake. Even athletes watch what they eat, and in fact they focus on nutritious, high-protein foods that support muscle development.

Exercise has significant limits as a weight loss tool. It increases your hunger and can increase your vulnerability to calorie splurges. Exercise assists with weight loss, but it is not a panacea. If you are serious about losing weight, you have to give proper weight to the calorie-cutting portion of the weight-loss formula.