What I found in rowing was a team sport that demanded total dedication, physical perfection, and an acceptance of pain and discomfort. Rowing first introduced me to my need for self-inflicted pain—the special nauseating deep-seated pain that accompanies repetitive interval training and racing. At first I merely followed this need intuitively. Only later would I begin to suspect that it is the continual exposure to, and mastery of, that discomfort that is an essential ingredient for personal growth.
— Timothy Noakes, “Lore of Running”