Just achieved a new PB at the Hampton Court Half (1:40:36). Felt strong throughout and managed a sprint finish.https://connect.garmin.com/modern/activity/1581651269
Planning to run a sub 3:45 in Paris in April (calculator suggests a 3:31 would even be possible), but paranoid about over-doing it heart-wise (this will be just my second marathon).
What sort of HR% should I be at during a marathon? I know that cardiac drift will occur over the run, so I am wary about maintaining a 7mph pace if my heart reaches a HR% that's unsafe.
I would just push myself through pain without these sorts of indicators and probably injure myself, so any advice would be appreciated.