Rowing is an outdoor sport done in a boat called a ‘shell’, for recreation or competition in which athletes’ race against each other on rivers, lakes or on the ocean. The number of rowers in the shell varies from 1, 2, 4, or 8. The person seated in the first seat is called the 'bow’, the rower closest to the stern is called the 'stroke’, while the coxswain is the ‘captain’ of the crew. There are two forms of rowing: Sweep and Scull. In sweep rowing, each athlete has one oar; in sculling, each athlete has two oars, one in each hand. Sculling is considered more efficient than sweeping. There are four phases of the row stroke, which include the catch (when the oar is placed in the water), drive, finish (when the oar is removed from the water), and recovery. Rowing is a low impact activity, applying minimal stress to the body. A typical race has four stages: warm up, start, body and sprint. To row, the athlete sits in the boat facing the back of the boat, and uses the legs, back and arms to lever the boat forward. Rowing provides full body conditioning as every stroke requires the calves, quadriceps, hamstrings, glutes, abs, obliques, pecs, biceps, triceps, deltoids, upper back, and lats to engage in the activity. It also provides cardiovascular benefits, builds endurance and tones the muscles. Rowing can also be done indoors, using an indoor rower machine can an ergometer. It is used for training during the winter months by professional rowers, and also used generally by professional athletes and the average gym goer.