1. Exercise and Health: Dose and Response, Considering Both Ends of the Curve 
Harvey B. Simon, MD 
The American Journal of Medicine 
Volume 128, Issue 11, Pages (November 2015)
DOI: /j.amjmed
Copyright © 2015 Elsevier Inc. Terms and Conditions

2. Figure
The risk of heart attack as a function of weekly exercise in 16,936 male alumni of Harvard College. As compared with sedentary men, those who expended kcal/week in exercise enjoyed a 36% lower risk of myocardial infarction. Higher levels of total exercise did not confer additional protection, but strenuous sports enhanced the effect of total energy expenditure to a modest degree.
Source: Paffenbarger RS, Wing AL, Hyde RT. Physical activity as an index of heart attack risk in college alumni. Am J Epidemiol. 1978;108: (p 166).5
The American Journal of Medicine  , DOI: ( /j.amjmed )
Copyright © 2015 Elsevier Inc. Terms and Conditions