Apps Workout app with persistent heart rate alert

[Wando64]

Is anyone aware of a workout app that offers a persistent Heart Rate alert?
For "persistent" I mean an alert that will carry on playing and buzzing until the HR has gone back within the set limits.

Some apps, including WorkOutDoors (which I use at the moment), generate a single alert which is easily missed if I am running in a noisy or windy environment.
My old Polar HR Monitor used to provide a persistent alert and I have found it is really important to me.

Thanks

 

[Wando64]

The lack of responses makes me think that this function has not been implemented by anyone yet.
Maybe I should just see this as an opportunity to be the first to market with it.