Calculating TDEE after weight loss. Help check my math.

Hobartlemagne

I've been losing weight for a while and pretty soon I'm going to start weight training. I want to do the cleanest bulk I can, so I really want to fine-tune my numbers.

I've lost 18lbs in 111days with a daily allowance of 1500calories
(It was just a guess, that this amount would make me lose weight)

If we go by the measurement that 1lb of fat is worth 3500calories, then 18lbs is 63000cal.

63000cal divided by 111days is 567calories per day.

So- does that mean 1500+567=2067, which would roughly estimate my TDEE?

I want to get this right, so I can better do a clean bulk by adding 10% to TDDE

Lietchi

That's the correct calculation for your average TDEE over the past 111 days. But considering that a smaller body needs fewer calories I would do the same calculation for a shorter period of time, for example the past 30 days? At least if your current TDEE is what you're interested in 🙂

AnnPT77

What Lietchi said. Also, keep watching. You may find that in practice you need to add more calories than that estimate. If so, that need might not be immediate.

Some people see that happen, and anecdotally whether it happens, how long it takes to happen, and how big the effect is . . . those seem to vary individually.

Loosely speaking, what's behind this possibility is that calories in can affect calories out. With reduced calories eaten, the body may down-regulate certain processes, and up-regulate them on higher calorie intake.

It can be things like hair/nails growth, core body temperature, other autonomic processes; spontaneous movement (loosely, twitching, but more, like how often one changes posture when sitting, etc.); energy and ambition during daily life chores, job, hobbies, exercise sessions; etc.

If these kinds of adaptations have happened during loss, and they reverse, the calorie impact is noticeable for some people - low hundreds per day for some, potentially. You know how some people report feeling more energetic at a lighter weight? If that happens, it can matter.

Anecdotally - based on reading others' maintenance posts here - it can start at first but happen gradually, or kick in noticeably after a month or two . . . or not happen at all.

If you're trying to bulk - which would mean eating a bit above maintenance - it might even be a little more likely. It you haven't been lifting progressively during loss, I'd speculate that could also increase the odds. IMU, the science around calorie needs when lifting is still murky in spots, and it unquestionably requires calories to create muscle tissue.

Not a phenomenon to count on happening, but I think something to be aware of as a possibility, especially in context of a bulking goal.

Hobartlemagne

AnnPT77 wrote: »

It can be things like ... core body temperature

Ive been freezing my butt off lately. Im always having to wear one more layer of clothing that i used to.

AnnPT77

Hobartlemagne wrote: »

AnnPT77 wrote: »

It can be things like ... core body temperature

Ive been freezing my butt off lately. Im always having to wear one more layer of clothing that i used to.

Yeah. Some people think it's all about losing the insulating fat layer, and that can be a factor. But it's not necessarily the whole story. I lost weight when I was first at college (yes, really). I was cold all the time after that. This time, I lost to a similar weight, but wasn't cold.

Whether your cold is lower core temperature or less insulation . . . well, time may tell. It's a possible indication of down-regulation, though.

Best wishes!

PAV8888

Since your ultimate goal is a (lean) bulk, the goal is still a bulk. Not maintenance. Therefore even if the lighter current body would need less calories etc, the extra error is probably not very relevant in the context of wanting to reach maintenance and a very slight plus.

In fact, the state of "extra energy" which comes at times from having slightly (or not so slightly in certain situations where the guilty such as myself need to be protected) is part of what you're trying to achieve with and during the bulk. Because this allows you to do more, push for more, and of course have the energy and building blocks to achieve the bulk.

Your program, in my own personal opinion has more to do with the success you will find. Nutrition is supportive; not the main driver.

But your goal involves providing full maintenance plus a few extra calories, not providing less.

So I would run my numbers through the "sail rabbit" tdee estimator. I would estimate my overall TDEE AND my most recent TDEE based on my logging. I would see how close or far all these figures are. I would consider that I have my 10% fudge factor... and I would pick a starting figure somewhere in there.

Say 110% of lowest number as long as it remains clearly above the highest number?
Or say highest number to start with unless said number it is more that 115% above the lowest?
Or somewhere in between to start?

And of course you CAN adjust as time goes on. And don't forget that it is the scale LEVEL that counts not the daily or weekly readings on the scale. The weight TREND is what matters and you need a good 4+ weeks of data to be able to observe your trend, especially since you will also be dealing with extra food in the belly and exercise related water retention if you're hitting the gym hard.

Best of luck