Stock photography, photos: A man trail running Stock photos of A man running along a stream in the Sierra mountains of CA. Photograph: © William Stevenson Click for a larger image and more information Keywords associated with this stock photo: Running, runner, run, training, back country, action, active, effort, energy, determination, motivation, strength, strong, aerobic, desire, freedom, sierra, river, stream, snow, solo, alone, cold, self reliance, male, man, winter, California, sierras, horizontal, Outdoor, outdoors, outside, sports, sporting, sport, exercise, physical, fitness, outdoorsman, sportsman, adult, young, adventure, adventuring, twenties, 20, s, 30, thirties, one, 1, person