Workout app and this website don't agree

Appears someone else posted a similar issue but didn't elaborate, so I will.

Today via Google Fit, I exercised for 47 mins, burning just under 1k calories.

Have waited an hour for data to load to this website. Data on this website says I exercised 34 mins, burning 347 calories. Huge difference by a third!!

Not the 1st, 2nd or 3rd time the site has done this. It's irritating with a wtf???

I'd upload the Google Fit screenshot from today's exercise but it's not html and photo won't load to forum as a file.

Answers