Fitbit stats and anlysis – part 1 (the nerdy one)

So I’m going to start by trying to explain what my goal is with this post, as I fear that I may get it horribly round my neck, or make it really complicated.

I’ve been wearing a fitbit for nearly 18 months now and what I’ve realised is that the amount of calories burned (let’s say energy used – it’s more constructive) is not always proportionate to the number of steps taken. 

I’ll use some stats to illustrate what I mean in a minute but the reason that I wanted to share all of this is because I know that a lot of people struggle to reach their step target each day, which can be demoralising. Or they feel that the only way to meet their target is to run but without the energy to do so, they get frustrated.  But having kept an eye on things over a number of months, I think it’s more about general tweaking to our every day life style, maybe incorporating some HIIT training and perhaps making sure that we’re on our feet a lot on the days that we’re not forced to sit down for long periods. Now none of that is new but I just wonder if perhaps seeing things in black and white via stats, makes it all seem a bit more believable.

So now I’m going to try and demonstrate what I mean…..

I took this screen shot at 10.35am yesterday, by which time I’d run just over 20km and taken 22,433 steps. The energy used was 1,597 calories. Seeing those figures in isolation and without a reference point would make anyone think that it’s just not achievable on a regular basis and they would be right. But the point is, it doesn’t need to be.

Let’s do a comparison….

On Saturday 3rd June, I covered 23,665 steps in the entire day. This was roughly the same amount of steps as I’d done by 10.35am yesterday.

But let’s compare the energy used….

Although roughly the same amount of steps were taken on both days (22,433 vs 23,665) the energy used (calories burned) was much higher on Saturday 4th, compared to yesterday ( 2,641 vs 1,597).

Which got me thinking – on a very simplistic level of course – how could that be? Obviously it took a lot longer to use the same energy on Saturday 4th and my body had to use energy during that time just to keep me alive – but would that account for the difference?  

Now it could be that I’m just a real nerd on these things and that no-one cares – but I like things to add up in my pea sized brain and currently they don’t. And it got me thinking that for those who are really short of time, or who are struggling to lose weight, finding a way to optimize their steps/activity levels so that they use as much energy as possible, in as an efficient a way as possible, could only be a good thing.

So now I’m going to take a look at a completely different kind of day in terms of steps taken…

On Sunday 4th June, I took far fewer steps than on either of the days above – only 12,973 steps as opposed to 22, 433 steps (yesterday by 10.35am) or 23,665 steps (3rd June during the whole day). Given that the steps were almost half of what I’d taken on those other two days, I would have expected the energy used to be roughly half too. But it wasn’t….

In fact the energy used was far more – 2,902 calories as opposed to 1,597 (yesterday) or 2,641 (3rd June). Again, how can that be?  

So looking at the step “pattern” ie the period over which the steps are taken has to be critical, as does what activity is being done during the taking of those steps, together with your heart rate during the course of that activity.

Are you all still with me? I’m not quite sure that I’m with myself but this is where I think I’m headed with it….

Let’s just take a look at one more lot of nerdy stats before moving on. Actually I’m thinking that this post may have to come in two parts as I need to tidy up and put the washing away before the weekend arrives. Can you bear to tune back for more?!

This table shows my stats for the week May 29th to June 4th. It also shows a comparison with my activity levels for the previous week. In summary, I was much less active (which was intentional) in the week May 29th to June 4th than I was the week before.

During the week May 29th to June 4th, at 75,410 my steps were down 83,582 compared to the previous week. And at 56.30 km, I covered 68.48km fewer than the week before. On that basis logic tells me that I should have been burning less than half the energy (calories – per day) than the week before. But that wasn’t the case. My calorie burn decreased from 2907 per day to 2157, which was a decrease of 747 per day – significant but much less than might be expected, given that my activity levels decreased by more than 50%.   

I’m afraid that I’m going to have to leave it here or else I’ll have a miserable weekend because the house will be a tip – but I hope to continue with my musings tomorrow and in the meantime I would love to hear your thoughts. Perhaps I should wait until the post is finished before making it live but just imagine if I get run over by a bus on the school run and the most impressive body of uncompleted work in the history of the universe lays undiscovered on my laptop?

Of course I should add lots of caveats in here and say that first of all, I’m not obsessed by these stats. If I were, I would have realised all of this in about the first month of using my fitbit, not 18 months later. Oh and just to re-iterate I never weigh myself so I’m unware as to whether I’m putting on 2.1kg every week as my fit bit suggests (see screen shot above) – but I don’t think that I am. 

As we all know, good nutrition is important in this being “healthy” game and this post (not that I’ve reached any conclusions yet) isn’t designed to devise a way of eating as many cream cakes as you can whilst still staying slim – unless any of us has a red carpet event coming up and then of course all bets are off.

Also, there are of course many benefits to all types of exercise – it’s not just about energy consumption. I for one know that – I suspect that if I didn’t get out and run with my friends, we would have a rather large bill for the Priory. Plus it’s good for bone density, your respiratory system, muscle mass and so on – so I’m really not searching for a way for us to sit on our bums and still be healthy.

Finally, no animals or young children were harmed in the writing of this post but I may have bent my daughter’s boyfriend’s ear with my theories and for that Michael, I am truly sorry.



  1. Sue Wilty
    June 16, 2017 / 3:19 pm

    I don't understand it either – do you add in food that you consume? (I gave up with that after a day and a half – it's a huge faff!) maybe its to do with that??Sue xx

    • StyleGuile
      June 16, 2017 / 9:10 pm

      Hi Sue, I'm like you, I can't do with the faff of putting the food in so the mystery deepens! x

  2. kathynewlyn
    June 17, 2017 / 7:18 am

    hi Beth, great post and set me thinking… As you know, I'm a Fitbit fan but I don't think steps, if looked at isolation, are a good indication of fitness or activity, as it all depends how you do them. A 10K run followed by not much else for the rest of the day, will give you the steps and a bit of calorie burn but it will soon level off. I have found it's much better to be moderately active throughout the day, ie bit of housework, bit of gardening, a dog walk etc. Only problem with this is that work gets in the way!Seven hours at a desk is not good for you. On work days i still get my 10,000 steps in, but calorie burn is less than if I have been home, 'pottering' and done the same amount of steps. I do the food inputting. and it can be a faff… but it helps keep me on track. Right, off for a quick run before it gets too hot!Kathy x

  3. Julie Garvey
    June 18, 2017 / 10:25 am

    Gosh yes very confusing. Hope you get to the bottom of it and let us know. I always have believed for every mile I run I burn 100 calories, guess that would tie in with your 20k run, as for the rest of the stats I'm stumped!

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.