Both the Samsung Gear 2 (SM-R380) and Gear 2 Neo (SM-R381) have recently got updated to Tizen version 220.127.116.11, by the way of a 20Mb update. We now have Blocking Mode in the settings, which like the name implies, lets you block the notifications on the Smartwatch.
There are two blocking options:
There are also other improvements to S Health and general stability. You can download it by using the Gear Manager application on your Samsung phone or by downloading the file from Sammobile Firmware section. Firmware R380XXU0BNE5 for the Gear 2, and R381XXU0BNE5 for the Gear 2 Neo