Is there a better way to connect Athletes

Do you mean one athlete authorizes your app, then you get their data, then this athlete is deauthorized to free the slot for another athlete? That should work in general, but beware that there are reports that deauthorizing an athlete didn’t immediately decrease the counter of connected athletes.

Yes. That is sort of what I was thinking. I’m just concerned about how do you scale the app in a timely fashion if we have to limit the number of users to under 1000.

I was hoping maybe there are some people doing authentication a different way

There’s no other way to authenticate Strava users, but you could support other activity providers...

In my experience Strava have been helpful in increasing limits, as long as you’re getting very close to the limits and your app is behaving well with the API.

Apart from that a recommendation for early stage scaling with low user limits is to not hesitate to deauthorize users who don’t interact with your app. Many will sign up and never return. Deauthorize them to free up spots for those who will engage.