STUDY: WALKERS BURN MORE CALORIES THAN PREVIOUSLY THOUGHT
Do you hate to run and like to walk, but think that walking doesn’t burn as many calories? A new study has some encouraging news: The equations commonly used to predict the number of calories burned during walking count too few calories in nearly all cases on level surfaces.
Here’s why: Standardized equations commonly used to predict or estimate walking energy expenditure assume that one size fits all. Plus, the equations, which have been in place for close to half a century, were based on data from a limited number of people.
A new study at Southern Methodist University, Dallas, found that under firm, level ground conditions, the most commonly used standards are relatively inaccurate and have significant bias. The standards predicted too few calories burned in 97 percent of the cases researchers examined.
A new standardized equation developed by SMU scientists, however, is about four times more accurate for adults and kids together, and about two to three times more accurate for adults only.
The new equation is formulated to apply regardless of the height, weight and speed of the walker. And it’s appreciably more accurate. Study results, along with the new equation, were published earlier this year in The Journal of Applied Physiology.
The economy of level walking is a lot like shipping packages. There is an economy of scale. Big people get better gas mileage when fuel economy is expressed on a per-pound basis.
The SMU equation predicts the calories burned as a person walks on a firm, level surface. Ongoing research is expanding the algorithm to predict the calories burned while walking up- and downhill, and while carrying loads.
The research comes at a time when greater accuracy combined with mobile technology, such as wearable sensors like Fitbit, is increasingly being used in real time to monitor the body’s status. The researchers note that some devices use the old standardized equations, while others use a different method to estimate the calories burned.
NEW EQUATION CONSIDERS DIFFERENT-SIZED PEOPLE
- Bigger people burn fewer calories on a per-pound basis of their body weight to walk at a given speed or to cover a fixed distance.
- The older standardized equations don’t account for size differences; rather, they assume that roughly one size fits all.
In general, the new metabolic estimates can be combined with other physiological signals such as body heat, core temperature and heart rate to improve predictions of fatigue, overheating, dehydration, the aerobic power available and whether a person can sustain a given intensity of exercise.
For more information on walking, contact Maurie Cofman, CMES, CES, TBMM-CES, Personal Trainer, Certified Medical Exercise Specialist, Health Coach and Corrective Exercise Specialist in the St. Louis, Brentwood, and Clayton, MO area.