No. Gyroscope accounts are completely private by default, so only you'll be able to view your profile. However, there are a few optional ways to open your profile to share.
One way is to add friends on Gyroscope. Friends give each other full access to view their profiles—so you should only add people you trust.
Another other option is to go to settings and set your account to be public instead of friends only. It makes it really easy and convenient to share, since anyone in the world will be able to see it. Some people enjoy the transparency and accountability this creates, while other people would rather keep their data more private. It is up to you!
If you create or join a group, that type of data will be shared with the members. For example, if you join a running group, the other members could see your latest runs, but nothing else (like your weight). If you set up a weight loss group, then that info would be shared instead.
The final and most granular way to share is by manually exporting images from the iPhone app. This gives you the ultimate control over not only what data someone sees, but the exact presentation. Only images you’ve specifically shared or saved and sent to someone would make it out into the world.