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Change in Submaximal CRF & All-Cause Mortality

Mayo Clin Proc; ePub 2018 Jan 5; de Lannoy, et al

A 5-minute submaximal test of cardiorespiratory fitness (CRF) was able to identify adults who maintained or improved submaximal cardiorespiratory fitness (sCRF) and were less likely to die from all causes during follow-up than were adults whose sCRF decreased. This according to a prospective study with a least 2 clinical visits between April 1974 and January 2002 conducted to assess the relationship between change in sCRF and mortality risk during follow up. Participants include 6,106 men and women. Researchers found:

  • The mean change in sCRF at follow-up for all participants was -0.5±10.0 beats/min, and the mean change in maximal CRF (mCRF) was -0.3±1.4 metabolic equivalents.
  • Change in sCRF was related to change in mCRF, although the variance was small.
  • Hazard ratios (HRs) for all-cause mortality were 0.69 for stable and 0.59 for increased sCRF compared with decreased sCRF after adjusting for age, change in weight, and other common risk factors.


de Lannoy L, Sui X, Lavie CJ, Blair SN, Ross R. Change in submaximal cardiorespiratory fitness and all-cause mortality. [Published online ahead of print January 5, 2018]. Mayo Clin Proc. doi: doi:10.1016/j.mayocp.2017.11.020.


The relationship between fitness and outcomes, specifically cardiac outcomes and total mortality, is so robust that the American Heart Association has issued a scientific statement suggesting that fitness be assessed regularly as a “clinical vital sign.”1 The current study provides further data that improvement in submaximal cardiorespiratory fitness (sCRF) in middle-aged individuals, when compared to a decline in fitness over 4 years, decreases mortality by 40%. This is true regardless of other traditional cardiovascular risk factors. Physical activity decreases the risk of hypertension, type 2 diabetes, obesity, heart disease, stroke, cognitive decline, cancers of the breast and colon, and depression. It is important for physicians to talk with patients about engaging in healthy amounts of physical activity. While it doesn’t always seem as if people listen to our advice, advice from physicians about increasing physical activity leads to increased physical activity and increased physical activity leads to better outcomes. In 1 large trial, clinicians were trained to counsel patients for 3-4 minutes on increasing physical activity and that counseling was associated with increased physical activity at 2-year follow-up, as well as improvements in cardiorespiratory fitness as measured by maximum oxygen consumption.2 It is clear that most people do not get enough physical activity, but that increases in physical activity are vital to health, and that physicians’ advice makes a difference. — Neil Skolnik, MD

  1. Ross R, Blair SN, Arena R, et al; American Heart Association Physical Activity Committee of the Council on Lifestyle and Cardiometabolic Health; Council on Clinical Cardiology; Council on Epidemiology and Prevention; Council on Cardiovascular and Stroke Nursing; Council on Functional Genomics and Translational Biology; Stroke Council. Importance of assessing cardiorespiratory fitness in clinical practice: A case for fitness as a clinical vital sign: a scientific statement from the American Heart Association. Circulation. 2016;134(24):e653-e699.
  2. Writing Group for the Activity Counseling Trial Research Group. Effects of physical activity counseling in primary care. JAMA. 2001;286(6): 677-687.

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