Linda
I am glad that bbqdevil's *workaround* will "do the trick" 😉
Did you give the Timer idea a try yet? It seems to me that you are really needing to know when a certain amount of time has elapsed rather than *time how long you have being taking a reading*. Will you always have your hand free to tap the Watch? If so, why would you need the StopWatch going? - just look again at the sweep second hand on the clock.
It still remains that one should be able to set the time elapsed before sleep on a Chronograph w/ sweep second WatchFace though. I have searched and searched, to no avail.
I would suggest Siri, but it seems like many issues with Siri are ongoing and might just add another problem to the mix.
If I were you, I would Call Apple Support. It is sometimes tricky to get that option in the "breadcrumb" process Apple has instituted, but I was able to test the process before suggesting this:
- Click/Tap > https://getsupport.apple.com/GetproductgroupList.action
- Choose Apple Watch
- Choose "Setup & Usage..."

- Choose "The topic is not listed"
- Enter "set sleep duration" > [Continue]
(I know this in not exactly right, but the point is to be vague)
- Pick your poison - I would ONLY choose to talk with them on the phone
- Rehearse an "elevator pitch" statement* for the Specialist that you get AND when you get no satisfaction (likely) ASK FOR A SUPERVISOR
I have NEVER gotten an answer from a Level 1 Specialist - they are reading from a Knowledge Base not unlike all the resources available to us online
I have ALWAYS gotten satisfaction from a Senior Specialist (sometimes pretty high up the chain - but always)
Here's a sample "elevator pitch" that I actually sent as Feedback on the Apple Watch User Guide page
I need to change the duration 'before' the Watch goes to sleep while observing the Chronograph Watch Face.
I am a healthcare provider. I need to use my Watch to assist me in taking vital signs. On a normal watch, I would start counting pulses or respirations at a 15 second interval on the Analog Chronograph sweep second hand > stop counting at the next 15 sec. interval > multiply X 4 to get rate/minute.
The Watch goes to sleep after SEVEN (7) seconds !! Therefore I cannot see when 15 seconds has elapsed. I use both hands regularly in the procedure, so touching the Watch is not an option - or 'raise the Watch' to my viewing position.
I, and others in the ASC forum have searched for a Setting for the before sleep duration in vain.
Let us know what you decide.
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