May 26, 2010

Diet, Exercise, and Weight Loss

During an oral exam, one of my professors phrased it this way: “Wes, what do you think is more important—exercise or diet—for weight loss?” I’d always been an exercise physiology guy—a P.E. major in college—so exercise was a big part of my life and lifestyle. I answered quickly, “Well, I think exercise is more important.”
He looked surprised, then suggested, “Let’s walk through this objectively. If you wanted to lose two pounds of excess fat weight in a week, what would you have to do from an exercise perspective versus a diet perspective to accomplish that?”
It’s a relatively simple math problem at the heart of it. And ever since then, I’ve gone over the same calculations with almost every group of patients I’ve worked with. Every week we get together and go over new strategies to help them achieve their wellness goals relative to diabetes, heart disease, or depression.
2010 1515 page24If we’re going to lose two pounds of excess fat weight in a week’s time—which is a reasonably aggressive goal—we first need to know how many calories are in two pounds of fat. So we establish that every pound of fat has 3,500 calories. There’s a tremendous amount of energy in one pound of fat. That’s a good thing, from an efficiency standpoint, but it’s not a good thing from a weight-loss perspective.
The next question is “How much effort is it going to take to burn 7,000 calories in one week?” It’s obvious that we need to know how many calories are burned in the equivalent of a one-mile walk or jog or run. The data will surprise many people: we burn roughly 100 calories for every mile we walk, jog, or run. It doesn’t matter whether we’re walking or running: the main difference between those is the time factor—how long it takes you to do it.
Now you have all the information you need to plug in to that mathematical word problem. In class, you see the eyes of those who are quick at math grow big, and they say, “No, that can’t be right!” But when you calculate it out, it’s basically 70 miles of walking or running, or its equivalent, that would have to be done in one week’s time to burn two pounds of excess body fat. That translates into 10 miles a day, or three hours and 20 minutes of brisk fast-paced walking.
I tell my class participants, “Please understand! I’m not trying to discourage you from exercising; ?I just want you to understand the math about efficiency in weight loss between exercise and diet.”
Then I flash on the screen four unnecessary snacks or food choices, each of which represents 250 calories: a medium soda, a bagel, an ice-cream bar, a full cup of white rice. Now the question is: How much time would it take us to eat those snacks? How much time would it take us to avoid eating those four snacks or unnecessary food choices versus exercising to burn 1,000 calories every day, or two pounds of excess fat in a week?
When you start looking at it from that perspective, there’s very little debate.
Then why exercise at all for weight loss? Most snacking or unhealthful eating occurs because we are self-medicating a nagging sense of dis-ease. Exercise changes the way we feel. It both stimulates and relaxes the body, thus greatly minimizing our “need” to snack. The more consistent we are at exercising daily, the more likely we are to follow a nutrition plan that allows us to optimize health in every way. Regular exercise, just like good food choices, helps to improve concentration, focus, and intellectual acuity; it optimizes blood fats, blood sugar, blood pressure levels, and immune system function. And most important, it improves our receptivity to what the Spirit wants to teach each of us about living life to the full. 
Wesley Youngberg, Dr. PH., directs of lifestyle medicine clinic ( at the Rancho Family Medical Group in Temecula, California, and is coauthor and speaker for Win Wellness, a leading health evangelism resource available in multiple languages. He joins Karen Houghton in Naturally Gourmet, a health-related cooking show airing on the Hope Channel.