Hello Workout85,
Thanks for posting in the Apple Support Communities.
It sounds like you're unable to complete a workout without it pausing during the workout unexpectedly, right?
If we have that correct, let's confirm that you have the latest watchOS version installed with your Apple Watch. You'll need the latest iOS version with your paired iPhone installed, so check out this resource for assistance with backing up and updating your iPhone: Update your iPhone or iPad - Apple Support
As for updating your Apple Watch, check out the steps below. You can also find more details to help with updating, here: Update your Apple Watch - Apple Support
Update your Apple Watch using your iPhone
You can wait until Apple Watch notifies you when a new update is available. Tap Update Tonight in the notification, then go to your iPhone to confirm that you want to update overnight. At the end of the day, leave your Apple Watch and iPhone charging overnight so the update can complete.
Or you can update your Apple Watch with your iPhone manually:
1. On your iPhone, open the Apple Watch app, then tap the My Watch tab.
2. Tap General > Software Update.

3. Download the update. If asked for your iPhone passcode or Apple Watch passcode, enter it.
4. Wait for the progress wheel to appear on your Apple Watch. It could take from several minutes to an hour for the update to complete.
If you have the latest software installed on your iPhone and Apple Watch, see if the steps of the following resource help with getting accurate measurements with your Apple Watch. If you haven't adjusted the fit of your band, see if that may improve your results: Get the most accurate measurements using your Apple Watch - Apple Support
We hope that's able to help. If not, contact Apple Support directly to check into this with you in more detail.
Have a great day!