Research On The Measurement Of The Cardio Respiratory Fitness In Old People By Using 2-minute Step Test

Purposes:China is facing a serious aging problem,and monitoring the health status of the elderly from the perspective of physical fitness is important for the elderly to achieve self-care,improve the quality of life,and perform the social functions of the elderly.The reliability and validity of the 2-minute step test need to be further investigated,and the test-retest reliability,criterion validity,and discriminant validity of the2-minute step test should be examined to facilitate the selection of a scientific,valid and stable cardiorespiratory fitness assessment tool for the elderly,and to provide theoretical support for the application of the 2-minute step test as a method of measuring cardiorespiratory fitness for the elderly in China.Methods:Community-dwelling older adults aged 60-79 years were recruited to participate in the trial,which was divided into three parts.In the first part,the same 2-minute step test was administered to 87 older adults two days apart,and the ICC coefficient was used to test the test-retest reliability of the 2-minute step test;in the second part,92 older adults were randomly selected to perform the 2-minute step test and the FOX submaximal power bicycle test,and the subjects performed the second test one week after the first test,and the results of the 2-minute step test were correlated with the FOX submaximal power bicycle test to test the criterion validity of the 2-minute step test.The third part of the test was to examine the discriminatory validity of the2-minute step test by analyzing the differences in the performance of the 2-minute step test among 430 elderly people evenly distributed by gender and age,so as to test whether the 2-minute step test could discriminate between different levels of cardiopulmonary endurance in the groups of gender(male and female)and age(60-64,65-69,70-74,75-79).The 2 minute step test was used to determine the level of cardiorespiratory fitness at different levels of physical activity by monitoring the physical activity of 106 elderly people for one week and dividing them into high,medium and low physical activity groups according to the length of their medium and high physical activity.Results:(1)The ICC coefficient between the initial and retest scores of the 2-minute step test was 0.727,with the retest coefficient for the male human group being 0.722 and the retest coefficient for the female human group being 0.732.(2)The correlation coefficient between 2-minute stepping performance and the absolute value of maximum oxygen uptake measured by FOX method sub-polar power bicycle was 0.250,and the correlation coefficient with the relative value of maximum oxygen uptake was 0.231,the correlation coefficient between 2-minute stepping performance and the absolute value of maximum oxygen uptake in elderly women was 0.329,the correlation coefficient between 2-minute stepping performance and the relative value of maximum oxygen uptake in the age group of 65-69 years was The correlation coefficient was 0.351.(3)There were no gender differences in the 2-minute step test scores overall,only in the 70-74 age group where the 2-minute step test scores of males were significantly higher than those of females,and no gender differences were observed in the 2-minute step test scores of other age groups.The 2-minute step test scores in the age groups showed intergroup differences,with the 60-64 age group showing significantly higher scores than the other two groups,and the 65-69 age group showing significantly higher scores than the 75-79 age group.In addition,the2-minute step test scores also showed intergroup differences in the different physical activity groups,with the number of 2-minute steps completed by older adults in the middle and high physical activity groups being significantly higher than those in the low physical activity group.Conclusions:(1)The 2-minute step test showed good test-retest reliability in the 60-79 year-old community elderly population.(2)Weak correlation between the 2-minute step test and the maximum oxygen uptake inferred by the FOX method of sub-polar power cycling.(3)The 2-minute step test failed to show good discriminant validity on the gender dimension,but showed good discriminant validity on the dimensions of age and physical activity level.