Tibbi-i-kar

Introduction: the rating of perceived exertion (RPE) scale is an index for evaluating personal strain during dynamic activities. This study was carried out to determine the relationship between RPE and heart rate in the people with normal weight and overweight individuals during light and moderate physical activity levels under warm and hot experimental conditions.

Methods: This interventional study was conducted on 70 male students and employees (35 individuals with normal weight (BMI<25) and 35 with overweight and obesity (BMI≥25)). Each participant rested for 30 minutes and then performed a 60 minute light activity (2.8 kph on treadmill) with exposure to hot climatic conditions (37⁰C). In the other phase, the participant was asked to rest for 30 minutes and then performed a 60 minute moderate activity (4.8 kph on tread mill) with exposure to warm climatic conditions (32⁰C). The heart rate (by sport tester) and RPE 1-10 scale were recorded every 4 minutes. Finally, SPSS (ver. 16) was used using t-student test and Pearson correlation.

Result: There was a significant difference in the mean values of heart rate and RPE between two groups with normal weight and overweight in two climatic conditions (P<0.001). Also The Pearson's correlation coefficient showed that there was a positive relationship between RPE and heart rate in warm (r=0.75, p<0.001) and hot conditions (r=0.52, p<0.001).

Conclusion: The mean values of heart rate and RPE were higher in overweight and obese participants than those with normal weight. Also there was a significant correlation between heart rate and RPE but correlation coefficient was lower than other studies in warm and hot condition.