Does this literally mean 'how many hours did you run for?' or is it inquiring as to 'what time you are running?' ?
I'm pretty sure it's literally asking how many hours you ran for. "At what time" is always without the kwa as far as I've seen.
The best long distance runners are often Kenyan so ... maybe there'll be a chance to use it? I count my running time in seconds though, so if someone runs a lot I might ask them this sarcastically in awe of them.