1. Textbook of Work Physiology;Åstrand,1986
2. Updated physical activity guidelines for adults over 65, or age 50–64 with chronic conditions;ACSM,2007
3. Mothers, babies and health in later life;Barker,1998
4. Working postures and activities of lorry drivers – A reliability study of on-site observation and recording on a pocket computer;Van Der Beek;Applied Ergonomics,1992
5. A meta-analysis of physical activity in the prevention of coronary heart disease;Berlin;Am J Epi,1990