Results of my experiment are in! Do online calorie counters really provide a reliable estimate of how many calories I should be eating in a day to reach my goal?
The short answer is YES! But the caveat is that they are only useful if you have an honest and accurate assessment of what your activity level is.
Background of my Experiment
It's been 3 weeks since I re-started my training & diet program. I wanted to reassess what my daily caloric burn was so I could develop an effective meal plan. Calories In, Calories Out is really the most important factor here, with composition of the calories being the 2nd most important factor. So how many calories should I be eating to maintain my weight, so I know how many calories to aim for in order to cut my body fat % back?
Step 1: Testing Out the Online Calculators
I plugged my biological stats (Female/30 years old/5'8"/142 lbs) into a variety of mathematical formulas and online calculators and chose an Activity Factor somewhere between "moderately active" and "very active" because, while I workout hard 5-6 days a week, I also have a desk job. These formulas all produced the following results:
- FreeDieting.com says I should consume 2,068 calories to maintain my weight (at an activity level of working out "5x/week")
- Mayo Clinic says I should consume 2,100 calories to maintain my weight (at an "Active" activity level)
- Calorie.Net says I should consume 2,190 calories to maintain my weight (at a "Moderately Active" activity level). It also calculated my Basal Metabolic Rate ("BMR") - the number of calories I would need to consume to maintain if I were to lie in bed and do nothing ALL DAY - at 1,413 calories.
- Active.com says I should consume 2,500 calories to maintain my weight (at an "Active" activity level) - and 2,227 calories at a "Low Active" level.
- CaloriesPerHour.com gave me an RMR of 1,413 and a BMR of 1,450. These are both resting metabolic rates (the number of calories I would need to maintain if I did nothing but lie in bed all day). They then displayed a variety of Activity Factors to determine how many calories I would need to eat given how active I was throughout the day. I like this formula the best, because I was able to take an average of Moderately Active (1.55) and Very Active (1.725) and come up with a blended activity level I feel matches my desk job + intense after-work exercise routine. I multiplied an average of my BMR and RMR (1,432 calories) by an average of Moderately and Very Active (1.64) to come up with a maintenance calorie intake suggestion of 2,345 calories.
I really have no idea how "active" I should have classified myself, but it appears as though to maintain my weight, I should be eating anywhere between 2,100 and 2,300 calories.
But is this true? My goal is to shed about 3% body fat before I start a muscle building phase. In order to lose this weight ("cut"), I would want to reduce my diet by 500 calories to create a gentle deficit. But 500 calories off of 2,300 versus 2,100 yields a dramatic difference - either I'd be eating too many calories to make a progressive difference, or I would be eating too few given my athletic demands. Neither situation is ideal.
Step 2: Testing Out the Heart Rate Monitor
So, I plugged my stats into my Polar FT4 heart rate monitor and wore it for 24 hours yesterday to put those estimates to the test. I did a typical workout so as not to skew the results. Sure enough, after 24 hours, I had burned a total of 2,423 calories.
Conclusion
I'm gonna give a thumbs up to the online calculators, because given the pretty limited information they asked for, their estimates were not grotesquely off target. The problem is more with the user being able to adequately identify what their activity level is. Had I stuck with my original estimates and elected to subtract 500 calories from a 2,100 calorie diet, I would be in a deficit of almost 800 calories based on my real burn. And this was just the results of a day with a steady workout - no crazy circuits, no HIIT training.
With all of this in mind, I feel a LOT better about my idea of how much I should be eating in a day to reach my goals. Now the challenge is to create a menu that includes a diverse variety of real foods to meet these goals. I've been trying to stick to the below plan, but the strangest problem is that I am just not hungry enough to eat it all. What's a girl to do??
I know I lack a diversity of vegetables in there, but my IBS prevents me from eating anything more exciting than zucchini, spinach, iceberg lettuce and the occasional serving of peas. Carrots, celery, bell peppers, broccoli/kale/brussels sprouts, asparagus.... I could go on and on about the veggies my tummy can't handle. But anywho, I digress!