10000 Steps a Day Programs
Many health and fitness experts advocate wearing pedometers and taking 10000 steps per day. Taking these steps, which corresponds to walking a total distance of about 5 miles, will improve overall fitness and help control weight.
How many pounds can one reasonably expect to lose in a walking exercise program?
Caloric requirements of Walking
Ralph LaForge of the Duke University Medical Center provides a detailed analysis of the net caloric requirements of running and walking. LaForge defines the net caloric requirements as the calories required beyond what the body would burn if one had remained sedentary. (Technical detail: The calories used here are food calories, which are 1000 of the calories used in physics and chemistry.)
For slow walking (<3.5 mph) the body burns calories at a net rate of 0.77 calories per kg of body mass per mile. That corresponds to 35 calories per mile of slow walking for every 100 pounds of body weight. A 150 pound person will burn 53 calories per mile and a 200 pound person will burn 70 calories per mile.
For faster walking (>3.5 mph) or running the caloric requirements increase. For fast walking, the body burns calories at a net rate of 1.38 calories per kilogram of body mass per mile. That's about 63 calories per mile of fast walking for every 100 pounds of body weight. A 150 pound person will burn 94 calories per mile and a 200 pound person will burn about 126 calories per mile. Running rather than walking fast increases these figures about 10%.
Losing Weight
Losing a pound of fat, requires burning about 3500 calories more than is taken in via food. In round numbers, a person weighing a little over 150 pounds will burn about 100 calories per mile of fast walking. That means one would have to walk 35 miles to lose a pound. That makes it sound virtually impossible for the average person to walk his/her way to a significant weight loss.
So let's look at it a different way. 10000 steps per day corresponds to about 5 miles (2000 steps = 1 mile for most people). Hence walking 10000 fast steps a day burns about 500 calories a day. At 500 calories a day, it takes only a week to add up to the 3500 calories needed to lose one pound.
A totally sedentary person who works up to walking 10000 steps a day without increasing his or her caloric intake might reasonably expect to lose a pound a week. But be careful here, most people take some steps in the course of their normal activity, so if they start a 10000 steps a day program, they are not increasing their activity by that much. In addition one must resist the temptation to increase one's caloric intake by indulging too much after a hard workout.
What about a person who already does some walking? Adding 2000 steps (about 1 mile) to your daily routine, without eating more, works out to about 100 extra calories a day. These extra calories don't sound like much, but over a year they add up to 36,500 total extra calories burned. Call it 35,000 so you can have a few days off. These 35,000 extra calories burned correspond to a weight loss of about 10 pounds a year.
Walking 10000 steps a day will not produce the dramatic weight loss promised (but often not delivered) by many fad diets. However consistent daily walking combined with sensible eating habits can lead to significant weight loss over time. This slow and steady weight loss is healthier than dramatic quick weight loss or yo-yo dieting.
For tips on starting a 10000 steps a day program see:
Start Taking 10000 Steps a Day
Paul A. Heckert - I have a Ph.D. in astrophysics, over 30 years experience teaching physics and astronomy, and over 60 published research articles.
