Can I upload my Garmin Forerunner running track data from my iPad 2?
There are a few devices I found that have been recently added to the market


Garmin Ant+ adaptor for iPhone
Wahoo Key for iPhone


Both allow you to connect and record in real time exercise data in association with their and other third party apps (Garmin Fit and Wahoo have a list here)

What I have not been able to confirm is whether it will provide upload facility from devices after being out of range as you want. 

My assumption is yes it can, since you can get swim watch data entry.

All the products were originally designed for iPhone and I don't see any issue with running them on an ipad