There are two ways of uploading your data from your Bryton Cardio 40H GPS Watch to BrytonSport.com: by first transferring the data to your computer and then uploading, or uploading directly to the site from your watch.
I have spent some time looking at the options available for uploading data from your Bryton Cardio 40H GPS Watch.
You need an account on the Bryton site. You can create one quickly and easily using a Facebook account (this also allows you to share your activities on Facebook if you choose to). You need to be logged into said account.
You also upload your data to other sites such as endomondo: all you need to do is save your file in a compatible format. I used the .gpx format and had no trouble at all. It did not however include my heartrate data (I will be posting more about file formats and the data they contain in the near future).
Disclosure: the unit is being loaned to me for the duration of the review by Ballistic Bike Trading