Weight loss as a math problem, but which numbers are wrong?
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I am very impressed with your calculations OP!
What I am thinking is that either your maintenance calories are higher that you thought, which would give you a lower actual deficit, OR, calories burned through weight-lifting are lower than you thought, again meaning your deficit is lower.
I am also a detail-oriented person and like to understand the mechanics of everything that happens in my body. Did calculations just like you over the course of two months or so, and my weight loss was on the nose accurate, which blew me away because my FitBit One was confusing the heck out of me with its wild swings in calories burned.
Somehow everything evened out over 2 months, and I lost exactly the amount of weight (around 10 lbs) that I had calculated using the concept of total calorie deficit, and "one pound = 3,500 calories". However, my only exercise was walking, and I did not weight-lift or go to a gym at all.
The weight loss was very gradual, but 10 lbs over the course of 2 months still counts in my book
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Again, now you also are not taking into consideration water retention.
If he had the same tendency for water retention when he began his weight loss journey as he does now, then this extra weight has already been incorporated and can be ignored.
For example:
Starting weight: 180lbs + 5lbs water retention = 185
Ending weight: 170lbs + 5lbs water retention = 175
Net loss is still 10lbs.0 -
Maybe I will get jumped on here but you haven't taken into account any increase in muscle mass, have you always done that amount of excersize?0
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There is a pretty simple answer to your dilemma.
First, there will always be some sort of error is food logging. We are never 100% spot on. Our goal is to be as close to accurate as possible.
You just started out with weight training which will cause your body to retain water which will mask losses that should reflect on the scale. You need water retention, it will always be a factor.
Fitbit is not going to give you an accurate number of calories burnt because it's designed for aerobic activities not NEAT.
I say go with the plan of waiting another 4 weeks. Keep it up. Good start so far.
This.0 -
Maybe I will get jumped on here but you haven't taken into account any increase in muscle mass, have you always done that amount of excersize?
It's pretty rare to increase muscle mass all that much while eating at a deficit. The goal is to try to preserve as much of your existing muscle as you can while losing fat. But to build more muscle usually requires eating at a modest surplus.
But there could be some newbie gains, sure.0 -
thatstheticket wrote: »Again, now you also are not taking into consideration water retention.
If he had the same tendency for water retention when he began his weight loss journey as he does now, then this extra weight has already been incorporated and can be ignored.
For example:
Starting weight: 180lbs + 5lbs water retention = 185
Ending weight: 170lbs + 5lbs water retention = 175
Net loss is still 10lbs.
Hey just recently started weight training...
Nowhere did the OP say that.
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Even if we do everything 100% right on logging, our calories can be off (I do totally believe in CICO ). Here's some interesting info in regards to nutrition labels:
When it comes to food labels, there are problems too. A study published in the Journal of the American Dietetic Association found that the calorie content on frozen food labels was on average 8% higher than the label claimed — and on restaurant menus an average of 18% higher. What’s more, the author of the study, Susan B. Roberts, director of the Energy Metabolism Laboratory at the USDA Human Nutrition Research Center on Aging at Tufts University, says she suspects that those kinds of inaccuracies are common on other items on the nutritional food label as well. (Source:http://www.marketwatch.com/story/margin-of-error-on-food-labels-20-2013-11-07).0 -
Maybe I will get jumped on here but you haven't taken into account any increase in muscle mass, have you always done that amount of excersize?
With the exception of newbie gains, he's not building in a deficit.
OP, you have to account for normal daily fluctuations in there, (water retention, etc), plus errors in logging both food and exercise. I would do as others suggested and give it more time.0 -
First of all we do our best at being as close to accurate as possible but it will never be 100%, now first your logging:
Stay away from the Homemade entries in the database unless they are your recipes - you have no idea what someone else included
Stay away from Generic entries - again many are not accurate
You eat out a lot, and even if the nutritional information is given it's also not as accurate.
As for the fitbit, I love mine and it's actually pretty spot on. I also don't take it as an exact burn as I know nothing will be exact, but it's a nice way to look and see where I can tweak my calories up or down depending on the goal I'm after.
5 lbs in 28 days is damn good and you should be proud of that. The new exercise routine can be increasing water retention as has been stated already0 -
Ok, let me try to work my way through the responses and address them in order.
- Waiting another 4 weeks, check. Not like I was planning to change much at this point anyway
- Keep lifting and eating in a deficit, check
- I never said I expected to lose 10 pounds in 28 days. But at some point the math has to add up, or else one of my inputs is wrong. So the question is around either which input is wrong, or if I just need to wait longer for the bodily fluctuations to catch up.
- Regarding the question if I'm doing "TDEE or MFP method"... I've got myself set at a general daily calorie goal of 2000. I sometimes eat a little more, sometimes a little less. As you can see, the average for the month was just over 2100. Generally what happens is during the week I have no problem sticking to 2000 calories a day, and on the weekends I tend to go over due to social events, etc. So I wouldn't say I'm doing either method, per se. Just working out the details of what a reasonable deficit is going to be for me that allows me to make progress without inhibiting my eating too much.
- Regarding assuming a TDEE of 2740 based on 4 weeks of data, I think I'm going to hold steady for now, but it's a good idea that I will revisit as I accumulate more data. It totally makes sense, but I think I want to have more numbers before I start making assumptions.
- Regarding my weight training. This is new for me starting early January. I have done weight training in the past, but my wife and I just started SL 5x5 this month.
- Regarding increased muscle mass due to weight training, I've been tracking BF% using an Omron handheld that I've had for some time. I know, I know, they're not accurate, but it gives me consistent results from week to week, and I can see a trend line with it. For interests sake, January 9th was 261.6 35.9% BF (93.91lb of fat, 167.69 lean mass) and February 7th was 256.6 35.1% BF (90.07lb of fat, 166.53 lean mass), so both those numbers seem reasonable to me and it doesn't appear that I've increased muscle mass.
- I won't be ditching the fitbit. I like it, and as I said before, I don't think it's off by a large degree, given that the numbers it produces line up well within reason of any TDEE calculators I've played with online.
Thanks again for all the responses and appreciate the excellent (and terrible) suggestions!
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You've got a great plan and have gotten some really good advice.
My advice is that you need to remember that your body is NOT a simple machine. It's a complex mechanism with many, many variables. So complex that we have several large institutions that are still studying it in depth with billions in research budgets. If it were as simple as "I ate X and exercised Y, so I should weigh Z" we wouldn't need all that research!
It is a science, but it's an incredibly complex one, far more complex than most people realize. Your best bet is to keep tracking and adjusting and having a LOT of patience, so that eventually you can see action->result (btw, you will need far more data than one month for this!), even if the mechanism is unknown. From there, if you drives you crazy (it does me), then do research in nutritional journals to see if a possible mechanism has been identified.0 -
thatstheticket wrote: »Again, now you also are not taking into consideration water retention.
If he had the same tendency for water retention when he began his weight loss journey as he does now, then this extra weight has already been incorporated and can be ignored.
For example:
Starting weight: 180lbs + 5lbs water retention = 185
Ending weight: 170lbs + 5lbs water retention = 175
Net loss is still 10lbs.
This would make sense if water retention was constant over time, which it is certainly not.
If I have something like hot and sour soup or a bunch of pickles (which aren't bad in terms of calories but can have tons of sodium) I will gain about 3-4 lbs.....for a few days. It's just water retention. If he doesn't eat the exact same amount of sodium each day his water retention will go up and down by at least a few lbs.
That's why I weigh myself daily and focus on the 7 day average weight. It will still have some random water weight fluctuations but averaging over a week smooths things out a lot.0 -
Maybe I will get jumped on here but you haven't taken into account any increase in muscle mass, have you always done that amount of excersize?
It's pretty rare to increase muscle mass all that much while eating at a deficit. The goal is to try to preserve as much of your existing muscle as you can while losing fat. But to build more muscle usually requires eating at a modest surplus.
But there could be some newbie gains, sure.
Even newbie gains wouldn't be that great over just a 4 week period.0 -
That part is not true. Fitbits are totally designed for NEAT. A HRM is designed for aerobic zone activities. Fitbits aren't HRMs.There is a pretty simple answer to your dilemma.
First, there will always be some sort of error is food logging. We are never 100% spot on. Our goal is to be as close to accurate as possible.
You just started out with weight training which will cause your body to retain water which will mask losses that should reflect on the scale. You need water retention, it will always be a factor.
Fitbit is not going to give you an accurate number of calories burnt because it's designed for aerobic activities not NEAT.
I say go with the plan of waiting another 4 weeks. Keep it up. Good start so far.
Though I agree that water issues in the first month throw a wrench in your calcs, often.
OP- I did the math over 6+ months and my Fitbit did a good job of predicting my weight loss, over 35 lbs. You could fit the averages less well though, or track food less well. Knowing how much you vary from the predicted is all you need, though. If you want to lose twice as fast as you are, you know how much to reduce your intake by, for example.
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WalkingAlong wrote: »OP- I did the math over 6+ months and my Fitbit did a good job of predicting my weight loss, over 35 lbs. You could fit the averages less well though, or track food less well. Knowing how much you vary from the predicted is all you need, though. If you want to lose twice as fast as you are, you know how much to reduce your intake by, for example.
Good stuff, thanks. Funny enough, since I posted this thread two days ago, I lost 1.5 pounds Sunday morning and another 2 pounds this morning. The body is a complicated machine all right...
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WalkingAlong wrote: »Fitbits are totally designed for NEAT.
You know the Scooby TDEE calculator? And the one at IIFYM?
That's what is inside a FitBit.
All a FitBit does is use the motion sensor to guess where you are on the Sedentary -> Active scale, and then guess at your calorie burn based on the usual TDEE math you can find at any web site.
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