Use of heart rate reserve and rating of perceived exertion to prescribe exercise intensity in diabetic autonomic neuropathy.
ABSTRACT Individuals with diabetic autonomic neuropathy (DAN) exhibit an increased resting heart rate but depressed maximal heart rate. Thus, the purpose of this study was to examine the validity of using either percent of heart rate reserve (HRR) or a rating of perceived exertion (RPE) scale to prescribe exercise intensity in diabetic individuals both with and without DAN.
The subjects consisted of 23 individuals with type 2 diabetes, ages 45-75 years, with (DAN; n = 13) or without (No DAN; n = 10) clinical signs of DAN, as assessed by heart rate variability using the expiration-to-inspiration ratio of the R-R interval. Peak aerobic capacity was determined using a graded protocol on a cycle ergometer, with RPE, heart rate, and VO(2) values recorded at each stage.
The subjects were similar with the exception of depressed autonomic function in DAN subjects. Peak respiratory exchange ratio values were significantly higher (P < 0.05) in the DAN group (1.08 +/- 0.02 vs. 1.02 +/- 0.01 in No DAN subjects), although DAN subjects exhibited a significantly lower (P < 0.05) peak exercise heart rate. A similarly highly linear relationship between %HRR and percent VO(2) reserve (VO(2)R) existed for both groups (r = 0.98). A similar slightly weaker relationship (r = 0.94) was found between RPE and %VO(2)R.
In conclusion, in diabetic individuals, %HRR provides an accurate prediction of %VO(2)R and can be used to prescribe and monitor exercise intensity, regardless of the presence of DAN. The RPE scale is also a valid, albeit slightly less accurate, method to monitor exercise intensity in diabetic individuals.
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ABSTRACT: To evaluate the effect of 8-week moderate intensity aerobic (heart-rate reserve 40-60 %) exercise on neuropathy quality of life in type 2 diabetes. A single blind, parallel-group, randomized controlled trial was carried out in a tertiary setting. People with type 2 diabetes were eligible for the study if they had clinical neuropathy which was defined by a minimum score of seven on the Michigan diabetic neuropathy score. Following which, the patients were randomly assigned to an 8-week program by a computer-generated random number tables to intervention or control group. Repeated measure analysis of variance was used for data analysis (p < 0.05 was considered significant). There were 47 participants in the control group and 40 participants in the study group after randomization but 37 from the control group and 29 from the intervention group completed the final analysis. The two groups had a significant difference, pre-post intervention in scores of pain (F = 7, p = 0.01), sensory symptoms (F = 4.60, p = 0.04), restricted activities of daily living (F = 4.97, p = 0.03), disruptions in social relationships (F = 5.43, p = 0.02), specific impact on quality of life (F = 9.28, p < 0.001) overall quality of life (F = 28.72, p < 0.001), and total score (F = 31.10, p < 0.001). Degrees of freedom for all the components were 1, 62. Moderate intensity aerobic exercise is cornerstone in improving the quality of life of individuals with peripheral neuropathy in type 2 diabetes.Quality of Life Research 12/2013; · 2.86 Impact Factor
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ABSTRACT: 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. 3582 individuals with type 2 diabetes (age: 58.3±6.8 years; BMI: 35.9±5.9 kg/m(2)) 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. 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). 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.Journal of novel physiotherapy and physical rehabilitation. 07/2014; 1(1).
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ABSTRACT: To evaluate the effect of moderate intensity aerobic exercise (40%-60% of Heart Rate Reserve (HRR)) on diabetic peripheral neuropathy. A parallel-group, randomized controlled trial was carried out in a tertiary health care setting, India. The study comprised of experimental (moderate intensity aerobic exercise and standard care) and control groups (standard care). Population with type 2 diabetes with clinical neuropathy, defined as a minimum score of seven on the Michigan Diabetic Neuropathy Score (MDNS), was randomly assigned to experimental and control groups by computer generated random number tables. RANOVA was used for data analysis (p<0.05 was significant). A total of 87 patients with DPN were evaluated in the study. After randomization there were 47 patients in the control group and 40 patients in the experimental group. A comparison of two groups using RANOVA for anthropometric measures showed an insignificant change at eight weeks. For distal peroneal nerve's conduction velocity there was a significant difference in two groups at eight weeks (p<0.05), Degrees of freedom (Df)=1, 62, F=5.14, and p=0.03. Sural sensory nerve at eight weeks showed a significant difference in two groups for conduction velocity, Df =1, 60, F=10.16, and p=0.00. Significant differences in mean scores of MDNS were also observed in the two groups at eight weeks (p value significant<0.05). Moderate intensity aerobic exercises can play a valuable role to disrupt the normal progression of DPN in type 2 diabetes.Journal of diabetes and its complications 12/2013; · 2.11 Impact Factor