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How Many Calories Does a Weight Workout Burn?


#1

Hey guys I was reading an article recently that prompted this question…

Is there any way to calculate how many calories we burn when we lift? I am mostly doing a Bigger Faster Stronger type regimen and being a bigger guy Im curious as to how many calories I burn during AND post workout? Specifically how much does lifting elevate out BMR and for how long?

Thanks in advance


#2

That number is going to vary dramatically depending on the individual and what it is that they are doing.

Let’s just pretend you knew this number. Would that piece of information shape your approach somehow? Or are you just curious?

Edit: I didn’t notice that this is Mr. Thibaudeau’s forum, and did not intend to speak on his behalf.


#3

Nah that’s fine. You are essentially correct. Caloric expenditure will vary a lot depending on many variables. The weight lifted, number of repetitions, exercises used and even the density (rest intervals) will have an impact on caloric expenditure.

Not only that, the type of workout (low reps vs. higher reps vs. metabolic/crossfit circuits) will also affect which energy substrate you use the most during a session (phosphagens, glucose, fat).

As for how much a workout keeps caloric expenditure elevated for, studies have shown that once again many factors can have an impact… how much and what type of food you ate prior to the session (or if you were fasted for example).

So any calculation about how many calories you will use during a session is, at the very best, a fairly gross estimation


#4

The main thing I was wanting to know this for is to know how many cals I am burning losing weight but most importantly if there was a % that you guys know of how elevated our BMR stays after a weight training session and for how long? It always bets thrown out there about BMR being elevated for like 36 or 48 hours, but nobody says by how much on average it gets elevated.

If it gets elevated by a few percentage points its probably not going to be significant…but perhaps 10-15% would make a good dent in weight loss long term. Is any of this type of info available?


#5

Read my answer. You will not get a formula or evaluation that will be more than a gross and imprecise estimation because of various factors. So if you plan on calculating the exact number of calories you need every day with a formula, good luck. You might be in the same ballpark, but a 10-15% of error is the norm.

The best way to see, as a whole, if you are consuming an excess or deficit in calories is to do what you normally do. Record EVERYTHING that goes in your mouth (and has calories) over the course of a whole week (including portion size of course), and calculate how many calories you ingest.

Measure your body weight at the beginning of the week (morning weight of the 1st day) and after seven days (so morning weight on the 8th day).

Then take the food log and calculate your average caloric intake over the course of the week… let’s say that it was an average of 2850kcals per day.

Calculate the difference in weight between day 8 and day 1. Lets say you have lost 1lbs over the course of the 7 days.

Right off the bat we know that you have a caloric deficit because your weight went down.

Since it went down by 1lbs we can assume a deficit of between 3500 - 4250 over the course of the week, or 500-600 per day.

So we can assume that on average you are using 2850 + 500-600 = 3350 - 3450 kcals.

That’s not perfect, but outside of having access to a calorimetry chamber and spend your whole day in there you don’t have a much better solution.