Born in Glasgow, Williamson won the 1979 Summer Universiade 1500m title.[1] His running club was Springburn Harriers.[2] He still holds the Scottish national records for the 1000 metres (2:16.82), the Mile run (3:50.64) and the 2000 metres (4:58.38), as well as multiple Scottish U20 records (800m/1500/Mile/300m).[3] He currently works for Adidas in Germany as Vice President of the tennis business unit[citation needed] and has a son who is also an athlete.[4]