v. To do something that is both stimulating and relaxing.
2012
Tim Locke, head of marketing at Mark Warner, said there was a "growing trend for people wanting to combine fitness and well-being on holiday", which he put down to the Olympics…PR wags have even had coined the term "thrillax" to describe the trend.
2012
Our new favourite word is "thrillax" so be warned, it’s one that we expect to be somewhat overused in the short term on this blog!…To us thrillaxing is what more people should be doing with their free time — getting together with groups of friends, making your heart race with a mixture of exertion and fear then laughing together when the fear subsides and you reach the target.
2009 (earliest)
Yeah, freeriding is awesome. It's "thrillaxing", like skiing smoothly down a broad, intermediate slope.