I've been a Garmin Connect (GC) user for 4 years, a Strava user for 2 years, a Fitbit user for 5 months, and a MFP user for less than a week.

I had issues syncing activities across all four platforms, and since I couldn’t really find a clear solution, I will post how I have my four platforms connected and synced without duplicate entries.

<Background>

I track all my activities (road running/trail running/weight lifting/cycling) with my Garmin Fenix 3, and use my Fitbit Charge HR for daily HR tracking.

Before starting MFP, I had no issues uploading my Garmin connect data to my Fitbit and Strava.
The setup I previously had was:

1. Connect Garmin to Strava, and Strava to Fitbit
2. Track GPS activity with Garmin device and NOT with my Fitbit
3. Upload activity to GC
4. Uploaded GC activity gets synced to Strava
5. Synced Strava activity gets synced to Fitbit

* This only works with GPS activities, not indoor activities that do not get synced to Strava (ex: indoor weight lifting). For indoor activities, you have to record with both Garmin and Fitbit devices.


This way, I would be able to get my HR reading from the more accurate Garmin HR strap, as well as GPS data from my Garmin device into my Fitbit dashboard.

Once MFP came into the picture, things had to change, because:
- I wanted to sync my food consumption, which was logged via MFP, to both Fitbit and GC
- I wanted the accuracy of my Garmin device over my Fitbit tracker for my activities
- I wanted to have my activities synced across all four platforms
- Linking MFP with GC and MFP with Fitbit ended up duplicating my Garmin activities in Fitbit


<Solution>

The way I solved the duplicate activities from my Fitbit was to:

1. Link Garmin with MFP and Strava
2. Unlink Fitbit and Strava
3. Link MFP with Fitbit
4. Track activity with Garmin device
5. Upload activity to GC
6. Uploaded GC activity gets synced to MFP
7. Synced MFP activity gets synced to Fitbit

* This means that my Garmin activities still get synced to Strava, but Strava activities no longer get synced to Fitbit.
** This also means that my indoor workouts tracked with my Garmin will now get synced to MFP and Fitbit without having to track the activity on both my Garmin and Fitbit devices.


However, there are some drawbacks to the above setup.

1. My activities in Fitbit get an unappealing name such as ‘Running (jogging), 5.2 mph (11.5 min mile) (MyFitnessPal) at Tuesday, April 19, 2016, at 7:56AM’, instead of ‘Run’
> No practical harm done, but I personally prefer the simpler names
2. Activities in Fitbit no longer show the distance and pace of my GPS activities
> As I personally track the details of my GPS activities with GC, there is little loss, but I would still prefer to have the info on my Fitbit dashboard as well
3. All of the stick figure icons in my Fitbit exercise list are standing stick figures regardless of activity type, instead of biking/running/working out stick figures, depending on activity type.
> Again, no harm done, but I liked seeing the different stick figures

Does anybody know a better setup to properly sync activities across MFP, GC, Fitbit and Strava without the above shortcomings?
One way I can think of is to:

1. Link GC to MFP, MFP to Fitbit, GC to Strava, Strava to Fitbit
2. Track activity with Garmin
3. Upload activity to GC
4. Uploaded GC activity gets synced to Strava and MFP
5. Synced Strava activity gets synced to Fitbit
6. Synced MFP activity gets synced to Fitbit
7. Manually erase MFP activity from Fitbit and keep Strava activity in Fitbit

But this steps requires me to manually erase the duplicate activity after every activity I track, so I decided to not use this setup.
If anybody has any suggestions, I’d be all ears.

I hope this will help somebody!