When people retire and do not have as many obligations, they may not stay as active as they were while they worked, in terms of both mentality and physicality. There are many jobs which involve some degree of physical labor or movement, and pursuing these following a retirement can help people remain active and fit, rather than spend more time lazing around. Just as important as physical health is mental health and acuity, and working to an older age can help improve this as well. Since retirement often sets life at a slower pace, many retirees may not get the mental stimulation necessary to keep their minds sharp. When they return to work, they keep their minds engaged more, and therefore will be less likely to experience mental deterioration earlier on.