Turning vibrations off for some activities

Hi - does anyone know if it's possible to turn off all vibrations on an activity level?

I know how to disable them for the watch - however, it's really only during certain types of activity (eg long runs) where (especially if I am doing a HRZ workout) I want to be informed everytime my HR enters a new zone.

Failing that, it is possible to set up a hotkey to toggle them?

Thanks

Marc