Validity of Borg‘s category ratio (CR) 10 scale during maximal-graded exercise testing

Lee, On; CHUNG, JINWOOK; CHUNG, JINWOOK; Lee, On; CHUNG, JINWOOK; CHUNG, JINWOOK

¹Department of Physical Education, Seoul National University, Seoul, Korea
²Department of Sports Science, Korea Institute of Sports Science, Seoul, Korea

Correspondence

JINWOOK CHUNG , Tel: 82-2-970-9697, Fax: 82-2-970-9593, Email: cjw826@kspo.or.kr
JINWOOK CHUNG , Tel: 82-2-970-9697, Fax: 82-2-970-9593, Email: cjw826@kspo.or.kr

Received: February 29, 2016; Accepted: April 26, 2016. Published online: April 26, 2016.

ABSTRACT

PURPOSE:
The purpose of this study was to investigate the validity of Borg‘s category ratio (CR) 10 scale during maximal-graded exercise testing (GXT) and to examine the factors associated with validity for ratings of perceived exertion (RPE) in Korean adults.
METHODS:
We recruited 720 adult participants over 20 years of age. we divided the participants based on their sex and further subdivided them into five-year age groups, with 40 participants in each group. After exclusion of participants whose VO2max measurements were invalid or in-appropriately recorded, we had a total of 665 participants (327 male and 338 female). We measured the participants' height and body fat percentage. Physical activity and physical self-efficiency were surveyed. Steady-state heart rate, VO2, and ratings were record last 10 seconds in every stage and end of GXT. The collected data were analyzed by descriptive statistics, correlation analysis and regression analysis using STATA 10.0 SE statistics package.
RESULTS:
The CR 10 scale was strongly correlated with %HR max, %heart rate reserve (HRR) and %VO2max. Estimates for relative exercise intensity at each RPE can be calculated according to the equation %HRmax=50.251+8.351× RPE-.317×PRE2 for male (r2=0.779, p<0.001) and, %HRmax=55.838+7.895×RPE-.332×RPE2 for female (r2=0.728, p<0.001). The validity was relatively higher in males and younger group, But there were no difference between physical fitness, vigorous physical activity, and physical self-efficiency.
CONCLUSIONS:
We found that Borg’ CR10 is more effective than 15-scale RPE as a method of setting of exercise intensity in Korean adults.

Key words: Validity; Rating of perceived exertion; Category ratio 10 RPE; Exercise intensity