Dictionary style definition of 'mushing'. 

Text reads - 

mushing
​​​​​​​adjective
1. a sport or transport method powered by dogs. Traditionally in the snow, using huskies.
2. translation; HOLD ON TIGHT!

Product available in a variety of t-shirt colours and sizes. 

​​​​​​​100% polyester  Neoteric™ textured fabric with inherent wickability and quick drying properties. Self-fabric crew neck. Set in sleeve design. Fabric collar and cuffs. Self-fabric taped back neck.