Use of Actigraphs and Self Report to Measure Bouts and Intensity of Exercise in Cancer Survivors

Abstract

PURPOSE: Exercise intensity is measured using various techniques including heart rate, VO2 reserve, and perceived exertion (RPE). Actigraphs have been used to assess light, moderate, and hard intensity exercise and confirm self report physical activity. The purpose of this pilot study was to determine if the amount of self reported bouts and intensities of exercise matched Actigraph reports. METHODS: Twenty endometrial cancer survivors (Age=58.5y, BMI=31kg/m2 VO2= 18. 8ml/kg/min) were given a short term personalized exercise prescription after completing a graded sub-maximal cycle ergometer exercise test. Participants were asked to report all exercise sessions and intensities (RPE) in diaries for one week. Participants were also asked to wear an Actigraph during the same week. RESUITS: Nineteen survivors returned usable diary data and the Actigraphs for data analysis. Ninety-five percent of the survivors reported performing the amount of exercise prescribed in the first week. The self reported time of exercise matched the time and duration of exercise recorded on the Actigraph for 84% of the reported bouts of exercise. Self-reported intensity of exercise matched the Actigraph for 70% of the reported bouts of exercise. Of the 30% that was incorrectly reported, exercise intensity was over reported 42% and under reported 58%. CONCLUSIONS: The data suggests this sample of cancer survivors generally reported time and duration of exercise correctly. Intensity of exercise was less accurately reported. Previously sedentary participants in exercise studies may need additional instruction to identify appropriate exercise intensities before beginning exercise programs. Funding Source: NIHgrantsR01 CA1099919, R25 CA57730, P30 CA016672