Cardiorespiratory fitness levels and its correlates among adults with diabetes.

PURPOSE: The purpose of this study is to report cardiorespiratory fitness levels among adults with diabetes and report differences by demographic (eg, body mass index) and behavioral (eg, physical activity) variables.

METHODS: Data from the 1999-2004 National Health and Nutrition Examination Survey (NHANES) were used in the analyses. Cardiorespiratory fitness was assessed using a non-exercise prediction equation and through a submaximal treadmill-based test using heart rate extrapolation. Participants completed a questionnaire to assess various demographic and behavior variables. Seventy eight participants met inclusion criteria and constituted the analyzed sample.

RESULTS: The majority (55.1%) of participants were estimated as having low or moderate cardiorespiratory fitness. Results showed that for both methods normal weight individuals had greater cardiorespiratory fitness than obese individuals, and for the non-exercise prediction equation, participants who sat during the day and did not walk very much had lower cardiorespiratory fitness (mean = 26.1 mL/kg/min [95% CI: 18.9-33.4]) than those doing heavy work or carrying heavy loads (mean = 34.6 mL/kg/min [95% CI: 30.2-39.1]).

CONCLUSION: These results suggest that obese and inactive adults with diabetes may be at an increased risk for morbidities and mortality associated with low cardiorespiratory fitness. Physical therapists are encouraged to apply evidence-based principles for exercise prescription and physical activity counseling to help patients with diabetes regulate their blood glucose control and improve cardiorespiratory fitness.