The causes of leg pain can be musculoskeletal, neurological, or vascular. Shin splints and stress fractures can result from repetitive sports, such as running. Leg pain can sometimes indicate a serious vascular problems.
Noun. 1. altruism-the quality of unselfish concern for the welfare of others. selflessness. unselfishness-the quality of not putting yourself first but being willing to give your time or money or effort etc. for others; rural people show more devotion and unselfishness than do their urban cousins.
an apparently unselfish concern for others or behavior that provides benefit to others at some cost to the individual. In contrast to selfishness, altruism represents a need to help or assist others, without regard to rewards or returned favors. In animal behavior it is difficult to understand how altruism could evolve since natural selection operates on individuals.