I used to have a heart rate monitor, shortly after I took up running (so I guess mid-2008), but found it so unreliable, not to mention rather a faff, I shelved it.

Like many runners, it seems, I am a bit of a statto, so I might be expected to appreciate some more data to analyse, but I was never really clear what benefits I could get from it, and still don't really get it.

Should I rethink? Convince me!

Good comments Martin, and I can only speak from experience but i have found teh 220-age pretty accurate for me over the years (and i have and do push myself hard on training and racing). Resting HR 40 for the last 20 years but max has slowly decreased roughly in line with age....I totally agree with pushing yourself to the limit though, unless ill!

At 51 my absolute max is 175, tried and tested over many really hard sessions and I can hold a 165 - 167 BPM run over a 10k and still have enough for a 200m sprint at the end, so really I think my lactic threshold is reasonably high. My easy runs are of 6 miles plus at around 140 BMP. But strangely enough my heart recovery rate is always around 32 - 40 except for extremes of running (really fast/slow).

And whilst I'm at it my resting heart rate is 48.

So all in all the formulas only provide a guide and you will find your levels for max/min/LT and so on by lots of structured running and like me monitoring and analysing every run to provide your own profile.

Its normal for the 220-age to be a bit out for most people but not up at 181. Is the heart monitor working properly, they sometimes take a while  to setttle down. Why not check it by taking your pulse while wearing it? Not to worry you but it could be a heart flutter or irregular beat. The flutter or racing heart beat tends to come on during intensive effort and you will feel nauseous and weak. If you feel fine I'd suggest its the monitor not picking up the signal properly.

Hi went out for usual run walk today,have managed in the past to run 1 whole mile twice,without walking.Tried again today had to slow up a couple of times,managed 11m 10s,but when i checked heart monitor,gave readings 181-155-70,according to my mhr to age ratio max should be 167,the most i have recorded in the past 3months is 172.is this normal??.thanks