ABSTRACT
Biological Mechanisms ...................................................................................................................49 Physical Activity and Estrogen ...............................................................................................49 Physical Activity and Insulin Sensitivity ................................................................................50 Physical Activity and Immune Function .................................................................................51 Physical Activity, Energy Balance, and Weight Control ........................................................51
Previous Literature ..........................................................................................................................51 Recreational Physical Activity ................................................................................................51 Quality of Data on Physical Activity ......................................................................................52 Occupational Physical Activity ...............................................................................................68 Confounding and Effect Modification ....................................................................................68
Conclusions .....................................................................................................................................69 References .......................................................................................................................................69
