When we run, for the most part we are not working against gravity. If you could bound more like a gazelle, then you might be able to go faster, but that would take a different anatomy, more than a smaller gravity.
The extra strength of your 10x alien would mostly be to support them vertically. So yes, they would be able to lift more than us here on Earth, but that doesn't translate into horizontal speed necessarily. If they could bound like a gazelle, then maybe they would be a bit faster than us here.