Jessica L Unick1, Sarah Gaussoin2, Judy Bahnson3, Richard Crow4, Jeff Curtis5, Tina Killean6, Judith G Regensteiner7, Kerry J Stewart8, Rena R Wing, John M Jakicic. 1. Weight Control and Diabetes Research Center, The Miriam Hospital and Brown Medical School, Providence, RI. 2. Wake Forest University School of Medicine, Winston-Salem, NC. 3. Universitiy of Minnesota, Minneapolis, MN. 4. Phoenix Epidemiology and Clinical Research Branch, NIDDK, NIH, Phoenix, AZ. 5. Northern Navajo Medical Center, Shiprock, NM. 6. Center for Women's Health Research, Divisions of General Internal Medicine and Cardiology, Department of Medicine, University of Colorado School of Medicine, Aurora, CO. 7. Johns Hopkins University, Baltimore, MD. 8. Department of Health and Physical Activity, Physical Activity and Weight Management Research Center, University of Pittsburgh, Pittsburgh, PA.
Abstract
PURPOSE: To examine whether a subjective measure of moderate-intensity exercise (12-13 on Borg's ratings of perceived exertion scale; RPE) corresponds to the target heart rate for moderate-intensity exercise (40-59% heart rate reserve; %HRR) and to determine the characteristics of those for whom RPE does not appropriately estimate exercise intensity. METHODS: 3582 individuals with type 2 diabetes (age: 58.3±6.8 years; BMI: 35.9±5.9 kg/m2) underwent a maximal exercise test and minute-by-minute HR and RPE were recorded. Linear regression was used to determine the %HRR corresponding to an RPE of 12 and 13 for each individual. RESULTS: At an RPE of 12 or 13, 57% of participants fell within the target 40-59%HRR range, while 37% and 6% fell above and below this range, respectively. Participants with a %HRR ≥60% (above range) were more likely to be female (OR: 1.19; 95% CI: 1.01,1.40), African American (OR: 1.65; 95% CI: 1.35, 2.02) or Hispanic (OR: 1.57; 95% CI: 1.27, 1.95), have a higher BMI (OR: 1.03; 95% CI 1.01, 1.04) and HRmax (OR: 1.02; 95% CI: 1.01, 1.02), and lower fitness (OR: 0.90; 95% CI: 0.85, 0.94) and RPEmax (OR: 0.68; 95% CI: 0.63, 0.73), compared to those within the target 40-59%HRR range (p-values'<0.05). CONCLUSIONS: RPE appropriately gauges exercise intensity in approximately half of overweight individuals with type 2 diabetes; however, more than one-third of participants were at an increased risk of exercising at a higher than prescribed intensity when using RPE. Future studies should continue to examine the characteristics of individuals for whom RPE appropriately estimates exercise intensity and for those whom it does not.
PURPOSE: To examine whether a subjective measure of moderate-intensity exercise (12-13 on Borg's ratings of perceived exertion scale; RPE) corresponds to the target heart rate for moderate-intensity exercise (40-59% heart rate reserve; %HRR) and to determine the characteristics of those for whom RPE does not appropriately estimate exercise intensity. METHODS: 3582 individuals with type 2 diabetes (age: 58.3±6.8 years; BMI: 35.9±5.9 kg/m2) underwent a maximal exercise test and minute-by-minute HR and RPE were recorded. Linear regression was used to determine the %HRR corresponding to an RPE of 12 and 13 for each individual. RESULTS: At an RPE of 12 or 13, 57% of participants fell within the target 40-59%HRR range, while 37% and 6% fell above and below this range, respectively. Participants with a %HRR ≥60% (above range) were more likely to be female (OR: 1.19; 95% CI: 1.01,1.40), African American (OR: 1.65; 95% CI: 1.35, 2.02) or Hispanic (OR: 1.57; 95% CI: 1.27, 1.95), have a higher BMI (OR: 1.03; 95% CI 1.01, 1.04) and HRmax (OR: 1.02; 95% CI: 1.01, 1.02), and lower fitness (OR: 0.90; 95% CI: 0.85, 0.94) and RPEmax (OR: 0.68; 95% CI: 0.63, 0.73), compared to those within the target 40-59%HRR range (p-values'<0.05). CONCLUSIONS: RPE appropriately gauges exercise intensity in approximately half of overweight individuals with type 2 diabetes; however, more than one-third of participants were at an increased risk of exercising at a higher than prescribed intensity when using RPE. Future studies should continue to examine the characteristics of individuals for whom RPE appropriately estimates exercise intensity and for those whom it does not.
Entities:
Keywords:
diabetes; exercise; exercise prescription; obesity; ratings of perceived exertion; type 2 diabetes