Does anyone know what is happening to me?

[Sweatyfaced]

So I know fitbit heart rate monitors are wildly inaccurate blah blah blah but since I'm just measuring against myself i'm hoping this makes sense.

When I first got my fitbit my running gave me a heart rate which was in the "peak zone" for pretty much all of every run (last Sept). I never worried about it as I felt fine.

Over the last few weeks however, fitbit has been decreasing the percentage of my running which is taking place in the peak zone and this week, I had my first run out (5k on my normal route for evening with 89m of elevation) where the whole run was in the "cardio zone".

My pace was similar, the route was familiar, I felt like I was working just as hard. BUT I did have something left in the tank at the end. Does anyone know why this might have happened? Am I getting fitter or is my fitbit learning more about me or something else? Peak heart rate on runs also seems to have dropped.

[pinkaardvark Graduate10]

Probably need to change your username.

[Sweatyfaced Graduate10 in reply to pinkaardvark]

I definitely don't!! Still get very pink!! 😂

[huffnpuffin]

I presume your body is getting used to exercise and therefore not using as much energy to do the same work.

[AnnieW55]

Sounds like you're getting fitter!

[Sweatyfaced Graduate10]

So does that mean i need to work harder? I guess I am confused cos sometimes it still feels hard.

[IannodaTruffe Graduate10]

Your heart, lungs and muscles are all adapting and becoming more efficient.

[Sweatyfaced Graduate10 in reply to IannodaTruffe]

Great - so what do I do now? How do I step it up?

[IannodaTruffe Graduate10 in reply to Sweatyfaced]

If you want to continue to develop physically then you need to put your body through progressive overload. In simplest terms this means pushing harder sometimes (intervals or longer duration) to trigger further adaptation, while the remainder of your running is still at an easy conversational pace.

Most training plans provide this split of effort and it is generally considered that 20-25% hard running is sufficient. Have you read this guide to post C25k running? healthunlocked.com/couchto5...

[Sweatyfaced Graduate10 in reply to IannodaTruffe]

That was exactly what I needed, thank you.

I will run 10k next Sunday (looking forward to getting my badge on here) and I have now downloaded the C25k+ pod casts as well to help me out.

Had a bit of a disaster yesterday at Parkrun which upset me and made me think I should just give up but this has spurred me on and I'll be back out there on Tuesday for a trusty 5k in the dark!