The Body Of A Surfer
A surfer is lean without looking weak, and muscular without the bulk. Sharp muscle lines are perfectly symmetrical, and overall body balance creates that enviable athletic physique.
Paddling builds shoulder definition, strengthens the lower back muscles, and increases cardiovascular fitness. Duck-diving through waves builds arm strength: tricep strength in particular. The pop-up maneuver engages the core and pectoral muscles, and helps to build explosive power.
And the actual process of standing and riding the wave increases leg strength, flexibility, and engages all the postural.