"I've been snowboarding since I was a kid so I felt safe.
"I didn't realise until I looked at the video today! I was freaking out when I saw it and showed my friends who told me to put it on YouTube.
"I've heard rumours that there can be bears, but that it is really, really rare!"
Kelly claims she didn't realise the bear was behind her because she was singing the Rihanna track Work - which is as good a reason as any not to notice being chased by a wild animal.
If the video is genuine it's terrifying, showing glimpses of the bear lumbering after Kelly at speed down the hill, with her only just managing to outpace it on a steeper section of the slope. If, however, it is a hoax, it's an impressive one, having convinced many viewers online.
This isn't the first time a video of an animal on the ski slope has raised questions of validity. Last season a video seemingly capturing a skier passing a mountain lion at the side of the slope triggered a similar debate, with some crying fake and others completely taken in.
Earlier this season, a video of a supposed "Yeti" caught on camera on the slopes of Spanish ski resort Formigal also caused controversy.