Exercise Calories - Where is Your Error? Do you suspect MyNetDiary overestimates the number of calories burned from exercise? Exercise calories are estimated using your body weight, duration of activity, and exercise intensity. The exercise database contains data from groups of individuals.
Do you suspect MyNetDiary overestimates the number of calories burned from exercise? Exercise calories are estimated using your body weight, duration of activity, and exercise intensity. The exercise database contains data from groups of individuals. You, as an individual, might expend more, less, or about the same as the estimated values from the exercise database.
Exercise Intensity. Picking the wrong activity item means error in estimated calories burned. You can compare intensity levels of different items by checking the calories burned per minute (these values are automatically adjusted using your body weight). Are you picking an activity with the correct intensity level? Don't guess - measure! For instance, if you run, walk, or cycle, measure your miles or kilometers per hour. With a GPS device or a smart phone app that uses your phone's GPS, you can measure distance, time, and speed. Or you can simply choose a route where the distance is known, then time how long it takes to walk, run, or cycle that route. Simply divide distance by time to get your speed. You can even search items by speed to help you pick the best choice.
Time. Time recorded in stop-and-go activities (e.g. soccer, alpine skiing, weight lifting, calisthenics, abdominals, etc) is often overestimated since people typically record total time rather than net time actually engaged in the activity. For instance, only record actual lift time (seconds per rep x number of reps), not the total weight room time.
Activity Level Setting. Avoid counting exercise calories twice. If you choose "sedentary" level, then log exercise above and beyond activities of daily living (which includes walking up to a mile). If you choose a higher activity level, then be sure it reflects your average daily exercise regimen. Activities that make up your overall activity level will NOT be logged (since doing so will double-count those calories). Please be sure to review activity level descriptions in your Account tab (web version) before selecting one. Many people choose activity levels that are too high.
Issue with Long Exercise Duration
When you log an exercise, the total calories burned for the day is overestimated by your prorated maintenance calories for the number of exercise minutes or hours logged. For example, if I log 4-hours of cross country hiking, the system shows that I burned 1491 calories. Given that my maintenance calories level is 1778 (displayed in "Personalized DRI" in Plan tab on web or "Weight Maintenance Cals" in apps), my total energy expended for the day is overestimated by 296 calories. See below:
1778 maintenance calories / 24 hours per day = 74 calories per hour
74 calories x 4 hour hike cross country = 296 calories
Note that this overestimation error will be present whether you enter exercise calories from your heart rate monitor or use MyNetDiary to estimate your exercise calories since total energy expenditure is calculated from the addition of logged exercise calories to estimated maintenance calories. As of July 2011, to correct this overestimation you can either record less time engaged in the activity or enter fewer calories, depending upon how you enter your data.
If you typically log more than an hour of exercise every day, then consider switching to a higher overall activity level and stop logging exercise. This will allow you to avoid the overestimation of calories associated with long duration exercise.