Date-night fitness challenge automation

My wife and I wanted a fun way to stay accountable with our fitness goals, so I built a shared challenge that turns Garmin activity data into a weekly scoreboard, a date-night fund, and a small amount of competitive pressure.

The rules are simple. Each week, the person with the fewest Garmin intensity minutes contributes $50 to the date-night fund. Zone 5 training minutes count double, so harder training gets extra credit. Each person is also expected to complete two weight-training sessions per week, and missing one adds another $25 penalty. After four weeks, the winner chooses the date night and can delegate the planning and organizing to the other person.

That structure made the challenge playful instead of purely punitive. The “penalty” still goes toward something shared, and the four-week cycle gives the challenge a clear finish line before it starts again.

The system only works if the tracking does not become a chore, so I automated the boring parts. Scripts pull activity data from Garmin, sync it into Google Sheets, backfill historical activity, calculate weekly standings, apply the contribution rules, and send a daily email showing who is ahead, who is behind, and what needs to happen before the week ends.

Google Sheets became the visible scoreboard and rule engine. It keeps the calculations transparent enough that the challenge does not feel like a black box, while the automation removes the need to manually copy workouts, compare activity minutes, or remember to send updates.

The daily email is a key part of the design. It makes the challenge visible without requiring either of us to open a dashboard every day. That small reporting loop keeps the system present in normal life and makes it easier to adjust before the end of the week.

This is a personal project, but the pattern is transferable: define the behaviour you want, make the rules visible, automate the tedious parts, and turn feedback into something people actually pay attention to. In this case, the result is a fitness challenge that supports consistency, competition, and date nights without creating another manual tracking task.