Books are a wonderful resource to use for research. They are good places to find in-depth background information on a topic, so you will find extensive high quality information in one place.
Exercise: Physical, Physiological and Psychological Benefits by 
Routledge Handbook of Sport and Exercise Systems Genetics by 
The Routledge Handbook of Sport and Sustainable Development by 
The Routledge Handbook on Biochemistry of Exercise by 
Wasserman and Whipp's: Principles of Exercise Testing and Interpretation: Including Pathophysiology and Clinical Applications by Go to the BC Library Catalog to search for books relevant to your research topic.
