Climate Change : It is the long-term change in average weather patterns of the earth. The key factors include the rise in average temperature of the earth, rising sea levels and maybe the declining average life span of humans.
Walking is a great exercise and usually is less tiring than running. But is of great benefit if done regularly. Walking can be done by elderly people also.
It is the well-being of emotional state, socially & psychologically. It is very important for a person to be mentally healthy.