Most people overestimate how hard they work out and how many calories they burn during exercise...
... and they underestimate how many calories they consume. Obviously that is not a good recipe for success if the only goal is weight loss.
Aaron E. Carroll, a professor of pediatrics at Indiana University School of Medicine, states, "Exercise has many benefits, but there are problems with relying on it to control weight. First, it’s just not true that Americans, in general, aren’t listening to calls for more activity. From 2001 to 2009, the percentage of people who were sufficiently physically active increased. But so did the percentage of Americans who were obese. The former did not prevent the latter."
Although we now know that there is much more to weight gain and loss than simply calories in versus calories out, the reality is that when someone consistently consumes more calories than they burn, the excess weight is not going to come off, and instead, will most likely creep up. And unfortunately, calories are a lot easier to put in than they are to burn off. For example, the Cheesecake Factory's Chicken and Biscuits, described in the menu as "Breast of chicken served over mashed potatoes with shortcake biscuits, mushrooms, peas and carrots. Covered with country gravy," has about 2,500 calories, according to the Center for Science in the Public Interest (CSPI). Following the strict calories in and calories out computation for weight control, you would have to run a full marathon, or 26.2 miles to burn off that single chicken meal!
Take another example. Think green tea is a healthful, low calorie drink? By itself, yes, but Starbuck's Tazo Green Tea Frappuccino has a whopping 560 calories. Have one of those in the morning and enjoy two glasses of wine in the evening and you add 250 calories for a total of 810 calories void of any real nutritional value. For a sedentary woman that probably accounts for about half her allotted calories for the day. And that sedentary woman, or for that matter even a moderately active woman is probably not going to go out and run 8 miles or exercise at a high intensity level for 60 minutes to burn that off.
The point is that it is probably easier and more realistic to make dietary changes to achieve weight loss than it is to sweat it all off. But since a large portion of clients hire a fitness trainer with the primary goal of losing weight that isn't necessarily something we want to throw out there at the first session. And we would be doing our clients a disservice if we did, because not only is it easier to lose weight through a combination of diet and exercise, but the added benefits of maintaining a fitness program almost always lead to a longer and healthier life.
Remember, you can't out exercise a bad diet! But with a combination of exercise and healthful eating habits you can achieve a healthy body weight and reap the numerous other benefits of attaining a fit heart and strong body.