Now that we know how to use metabolic rates to lose weight we can set a weight loss goal. Again, we will use my situation to set a weight loss goal. My daily metabolic rate is 1127 (resting) + 451 (daily activity level) = 1578 calories burned/calories out. To lose weight, calories in have to be lower than calories out but not less than 1200 calories in. (If I wanted to gain weight, calories in would have to be higher than calories out.)
If I kept my lifestyle (activity level) the same, my weight loss would be 1578 calories out – 1200 calories in = 378 calories a day. Since we have to burn 3500 calories to lose a pound it would take me almost 10 days to burn 3500 calories. To be exact it would take 3500 divided by 378 = 9.26 days. If I wanted to lose 10 pounds it would take me 9.26 days x 10 pounds = 92.6 days divided by 30 days (1 month) or just over 3 months.
But let’s assume I’m going to a class reunion in 2 months and I want to lose 10 pounds before then. 10 pounds = 3500 calories x 10 = 35000 calories I have to lose in 60 days (2 x 30 days). That’s 35000 calories divided by 60 days = 583 calories per day I have to burn. Since I can’t eat any less than the 1200 daily calories I’m eating, I to have to exercise to burn the difference between the 583 calories I need to burn daily and the 378 calories I can cut out with my diet. 583 – 378 = 205 calories I have to burn off with exercise. Now let’s see how much weight we would lose each week if we burn 583 calories each day. 7 days x 583 calories divided by 3500 calories (1 pound) = 1.17 pounds a week we would lose. Most nutritionists recommend a pound a week weight loss. Mainly because losing weight slowly helps you build healthy eating habits and you’re more likely to keep the weight off. If you’re otherwise healthy, you should be able to safely and healthfully lose about 1% of your body weight per week. More than 1% per week and you can damage your body, reduce your resistance to sickness like colds and flu and cut down on the amount of energy you have to get through the day. Our goal of 1.17 pounds per week is below the healthy weight loss of 1.5 pounds for someone weighing 150 pounds.
Now let’s assume our class reunion is in 30 days. Since we only have half the time, we would have to lose twice as much each week or 2.34 pounds. That is not a healthy rate for someone weighing 150. For me, it would also mean a 1200 calorie diet and 410 exercise calories per day. If we look at examples of calories burned while walking you can see how long you would have to exercise to burn 410 calories. And that’s doing it EVERY DAY!
Calories burned walking
Activity (1 hour)
|Walking, under 2.0 mph, very slow|
|Walking 2.0 mph, slow|
|Walking 2.5 mph|
|Walking 3.0 mph, moderate|
|Walking 3.5 mph, brisk pace|
|Walking 3.5 mph, uphill|
|Walking 4.0 mph, very brisk|
|Walking 4.5 mph|
|Walking 5.0 mph|