* your natural metabolism * normal daily non-exercise activities * what you burn through deliberate exercise.
Some sites might mix the last two to come up with an overall activity level. Others (including Spark) track your exercise seperately, and the multiplier only refers to NON-exercise activities. Neither approach is necessarily wrong, but mixing different methodologies is going to give you an incorrect answer.
A multiplier of 1.55 for non-exercise activities is extremely high - it would take a VERY physical job to justify a number that high (especially assuming a 5 day work week). The standard assumption is a multiplier of just 1.2 for a sedentary lifestyle. So maintenance calories is not your metabolism, but would be metabolism plus 20% plus exercise.
Also, a daily calorie deficit of 1000 does not need to be made up of 500 calories from food and 500 from exercise. 500 from exercise is certainly feasible, but it requires a good level of fitness to sustain a burn that high EACH day. Most people probably start at closer to 200 per day from exercise, and gradually build things from there over time.
I hope this puts those numbers in more context.
Fitness Minutes: (112,042)
46,222 3/19/13 11:50 P
Below is a link to SparkPeople's Registered Dietitian Becky Hand's tutorial as to how your calorie range is calculated. I hope this helps clarify matters.
Fitness Minutes: (470)
1 3/19/13 11:41 P
I'm a little confused. My BMR is slightly less than 1900, meaning that to maintain my weight I should eat that many calories. One site said to multiply BMR by activity level, in this case as I am moderately active I would multiply 1900 by 1.55. That equals 2,945 calories. In order to lose two pounds a week I would have to burn 1000 calories a day, taking 500 calories from food, and burning 500 through exercise. According to this, I would need to eat 2445 calories a day to lose weight. Spark, however, says to eat 1800 calories a day to lose 2 pounds a week. So, I'm confused. Which way is right? I really don't want to waste weeks doing trial and error.
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