Calories in, calories out?

I’m around 160lbs @ 5’9". FTP of 282.

I have a desk job but rest of time I’m pretty active, run to and from work 5 days a week which is 3.1 miles each way if I go direct but regularly tag on a extra mile or so if time permits on way to work. So although I am stuck at my desk most of day in addition to running, I go for a walk on a lunchtime to get my walking steps in. Regularly do ~18,000 steps a day (includes the running).

Do two weekend rides, one a tempo group ride with two free for all efforts up a climb and sprint finish ~2 hours long and then more social group ride of ~3 hours. Do midweek ride/trainerroad workout on a Wednesday.

Now I use a stryd running power meter and have power meter pedals on my bike so my calorie expenditure from running and cycling should be pretty accurate.

Last summer I cut down to 150 lbs used myfitnesspal to track food weighing it etc and got very lean etc but it felt quite severe at times. I want to reduce weight again as at minute I can pretty much eat what I want (within reason) and weight always hovers within a lb or two of 160.

This is where my question comes about if I know how much I have expended through exercise running or cycling because it is power based are those calories I should add to estimated calorie expenditure if I was just sat down all day? Or is it not as simple as that?

Basically, yes - it is that simple

You can use whatever BMR calculator you like - but just put yourself down as very low activity or sedentary and then add in your workout calories on top of that and you should end up with a pretty accurate target

I’m not sure how accurate running power meters are (everything I’ve read has said some are consistent, but without any known comparison points it is a bit of he said she said between the various brands) so I’m not positive how well you can trust a calorie or kJ number from one - but that’s a bit of a different story


Running power meters was covered on the DC Rainmaker/ GPLlama podcast this week, as Ray was testing the new Stryd which will take into account wind (which the earlier one’s didn’t). There was a bit of a throwaway discussion about how there isn’t actually an agreed running power calculation. So the stryd is probably consistent, but there’s no real measure of accuracy (was my take anyway).

fwiw, in the calculators for TDEE, I use the somewhat active, as I generally get the 10,000 steps regardless of runs. Garmin Connect gives average stride length (for me, using HRM-RUN anyway), so I guess you could take away running steps and see where that leaves the step counts?

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Thanks, glad it is that simple as previously heard mix messages due to calories estimates etc but with it coming from power it is more accurate measure of actual work. Only calories I will look to add to my BMR are from running and cycling. Any additional amounts from steps etc I will just tweak.

Funnily enough regardless if running power is accurate to measure energy expenditure or not for some reason when it imports calories from my runs into Myfitnesspal it is normally about 10% lower than output stryd gives me so I’ll use lower figure and work from that too :slight_smile:

I also track in MFP and use the “sedentary” (if this is how it is called in English) as activity level. This means minimal contribution of non-exercise activities to my BMR. BMR ist at around 1600kcal. Sedentary option adds about 400kcal.

I also track with Stryd. Sure, not perfect, but I still like it since I run a lot in the mountains. However, overall running volume is not so huge, thuse the error potentially introduced mudders in the overall uncertainty.

In the end one has to cross check with the scale. If the calories balance is even and the weight remains constant the overall assumptions seem sort of o.k. If you lose/gain weight something is wrong.

However, these days I only track food on heavy training days, e.g. when I get over ~4000kcal total energy requirement. I consider underfuling exercise days as very dangerous once you don’t have to loser weight anymore.

It may have changed, but when I started tracking mfp seriously underestimated my BMR/ TDEE. I was 120kg and it was giving me a target of less than I’m using now to drop a few kg at 74kg. I stopped using it - another forum gave a formula for working it out that I put into a spreadsheet, but there’s also Scooby’s.

mfp may have improved, but might be worth a cross check. It’s about the only bad thing I could say about the app though!

Everything to do with calories in and out is not accurate, it’s all estimates. If you’re fine with that, go ahead. I gained weight using MFP and calories in/out.

My position is that calories are an archaic estimation and measure that doesn’t do the job.

I’ve felt much healthier and fitter for training measuring protein primarily, then other macronutrients and only keeping an eye on calories. It’s not hard work, I still use MFP one week per month to see if I’m on track.

This combined with eating regularly and fuelling workouts has worked well since January.