Determination of reference values of 6-minute walk test and heart rate recovery time in adult individuals without disease affecting exercise capacity

The six-minute walk test (6MWT) is a functional test conceptually performed in a submaximal effort, which has been proposed to reflect activities of daily living. . However, data on reference values of 6MWT that can be used in clinics are limited in our country. The aim of this study was to determine the normal 6MWT values in healthy individuals admitted to cardiology polyclinics and to investigate the influence of factors as demographics, anthropometrics, and heart recovery rate (HRR) on 6MWD. The study was conducted with remaining 263 healthy and volunteer individuals obtained after using exclusion criteria on 2773 individuals admitted to cardiology polyclinic between 03/15/2019 and 09/15/2019. Demographic and clinical data of participants were recorded. Hemogram, lipid profile and thyroid hormones were included in the analysis. Oxygen saturation, Borg-dyspnea scale, Borg-fatigue scale and heart rate were evaluated before and after 6MWT. Moreever, the relationship between heart recovery rate (HRR) and 6MWT distance was evaluated. Mean 6MWT distance was 526 ± 79 m (range 369-810 m). The walking distance was 531 ± 95 m for males and 523 ± 70 m for females. The walking distance in 6MWT was negatively correlated with age, body mass index, post-test Borg-dyspnea score, HRR and total cholesterol. However, height, sistolic blood pressure BP, diastolic blood pressure, pre-test O2 saturation, post-test O2 saturation, pre-test heart rate, post-test heart rate, post-test Borg-fatigue score, hemoglobin level, blood glucose level, TSH, LDL-cholesterol, HDL-cholesterol and triglycerides were not correlated with walking distance. The walking distance was significantly shorter in participants within sedentary lifestyle. In our study, reference values of 6MWT which can be used in clinics were obtained. Moreover, demographic and clinical factors associated with 6MWT were identified. The HRR may be a new parameter that can be used to evaluate participants during 6MWT. Key words: six minute walking test, walking distance, heart recovery rate