Just wear a second watch and use it to record stoppages. I don't like the idea of 'stopping a watch' as i want a true record of time elapsed
Spintso has total time elapsed, time left including stoppages and how long it has been stopped. I wear a cheap second watch as back up but never look at it.
https://i.ytimg.com/vi/3WG2Sv0SI_w/hqdefault.jpg