Both devices are waterproof, featuring the Move IQ auto activity detection technology and can sync with the Garmin Connect mobile app and web service.
The update to the fēnix 3 multisport watches includes Garmin Elevate wrist-based heart rate technology, additional activity profiles and new watch bands.
The Index Smart Scale and vívosmart HR join Garmin's line-up of connected health/fitness products; they will be available next month for $149.99 each.
The new watches are Forerunner 230, Forerunner 235 and the Forerunner 630, all of which are readily available for purchase from Garmin's website.
OffTheScale provides a Garmin wearable device to each of its participants, allowing them to measure steps taken, calories burned, activity duration and more.
The wearable is expected to begin shipping in Q3 and will have a suggested retail price of $169.99 or $199.99 when bundled with a heart rate monitor.
Both devices can store up to 20 hours of heart rate data during swims, and send real-time heart rate when the user is out of the water.
Garmin's vívofit fitness band has been chosen by Medidata because of the ease of use provided by its year-long battery life.
The navigation giant used the big show in Vegas to announce three new smart watches, updated Vivofit smart band and revamped online fitness community.
With a price tag of $449.99, Garmin's device caters towards serious athletes, delivering detailed stats on swimming, biking, and running.