Share this article on:

The Impact of Race and Higher Socioeconomic Status on Cardiorespiratory Fitness

Howard, Erica N.1; Frierson, Georita M.2; Willis, Benjamin L.1; Haskell, William L.3; Powell-Wiley, Tiffany M.4; DeFina, Laura F.1

Medicine & Science in Sports & Exercise: December 2013 - Volume 45 - Issue 12 - p 2286–2291
doi: 10.1249/MSS.0b013e31829c2f4f
Epidemiology

Purpose: Previous studies suggest that African Americans (AA) have lower levels of cardiorespiratory fitness (CRF) than their Caucasian (C) counterparts. However, the association between CRF and race/ethnicity in the context of higher socioeconomic status (SES) has not been explored.

Methods: We evaluated 589 AA (309 men and 203 women) and 33,015 C (19,399 men and 8753 women) enrolled in the Cooper Center Longitudinal Study. Education years and access to a preventive health care examination were used as a proxy for higher SES. Data were collected from a questionnaire, maximal treadmill exercise stress test, and other clinical measures. The outcome variable was CRF, which was stratified into low fit (quintile 1 of CRF) and fit (quintiles 2–5). Multivariable regression was used to compare adjusted mean CRF between groups. P values were adjusted for unbalanced sample size and unequal variance between groups.

Results: The mean education years were similar for AA and C men at 16 yr; however, AA women had more years of education than C (15.8 vs 15.2 yr, P = 0.0062). AA men and women had a significantly higher prevalence of being unfit compared with their C counterparts (men 26.7% vs 12.6%, P < 0.0001; women 21.3% vs 8.4%, P < 0.0001). The adjusted mean estimated maximal METs were 10.9 vs 11.7 and 8.8 vs 9.8 for AA and C men and women, respectively. Fully adjusted odds ratios revealed that AA men had more than twice the risk of being unfit compared with C men. A trend persisted for AA women to have a lower MET value than their counterparts.

Conclusions: Despite comparable higher SES, lower CRF existed among AA men versus C men. These results suggest that CRF may not be mediated strictly by environmental factors related to SES.

1The Cooper Institute, Dallas, TX; 2Department of Psychology, Howard University, Washington, DC; 3Prevention Research Center, Department of Medicine, Stanford University, Palo Alto, CA; and 4Cardiovascular Pulmonary Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD

Address for correspondence: Erica N. Howard, M.S., Clinical Investigations,The Cooper Institute, 12330 Preston Road, Dallas, TX 75230; E-mail: ehoward@cooperinst.org.

Submitted for publication January 2013.

Accepted for publication May 2013.

© 2013 American College of Sports Medicine