The World Health Organisation (WHO) have identified three aspects of fitness that affect a person's ability to complete those everyday tasks of life effectively and efficiently. These are: Physical Health With good physical health, a body can cope with the physical demands of everyday living; walking to school; running for the bus; cycling to the shops. All these can be done without any excess strain or demands on the body. The body systems function efficiently and there is no illness or injury. Mental Health Good mental health allows people to cope with the emotional demands of everyday life: having a positive outlook on life. Social Health Being socially healthy includes having friends and help from others, making a contribution to society and being valued by it. It involves developing new relationships with a vast range and variety of people from different cultures and backgrounds.