To develop a simple test of endurance capacity in the elderly, we evaluated the reliability and validity of the shuttle stamina walk test (SSTw), in which the running in the shuttle stamina test (SST : 3-minute shuttle running along a 10-meter course) was changed to walking.
We found that: 1) The walking distance in the SSTw was correlated with Vo₂max (r=0.827), 2) the walking distance showed a correlation between the first test and a re-test (r=0.853), 3) the mean peak heart rate during the test was 86.3% of the estimated maximum heart rate with no difference according to age or sex, 4) subjective evaluation of the intensity of exercise was expressed as“fairly light”or“somewhat hard”by 73.7% of the subjects, 5) the results of the SSTw reflected the subjects' self-evaluation of endurance capacity, and 6) the age-related percentage reduction of the walking distance in the SSTw was similar to that in V₂max in subjects aged 40 years and above.
These results suggest that the SSTw, a simple test of endurance capacity that can be performed safely over a wide range of middle-aged to elderly people including those in late old age and those with a low fitness level, has sufficient reliability and validity.

BACKGROUND: The number of adults aged over 65 years is rapidly increasing in several Southeast Asian countries. Muscle mass decreases with age, leading to sarcopenia. The primary objective of this study was to determine whether differences exist in the body composition and physical strength, according to ethnicity, among community-dwelling Japanese and Thai older adults living in Chiang Mai Province, Thailand. METHODS: A survey was conducted in February and March 2019. Japanese and Thai adults aged ≥ 60 years living in Chiang Mai Province were recruited through community clubs. Participants completed a self-administered questionnaire that enabled collection of data on age, sex, educational background, marital status, annual income, current medical conditions, smoking and alcohol consumption, and exercise habits. Measurements were collected on height, weight, body composition, blood pressure, hand grip, and walking speed for 6 m. Body composition was measured using a standing-posture 8-electrode multifrequency bioimpedance analysis analyzer. Hand grip of each hand was measured with the patient in the standing position using a digital grip dynamometer. Multivariable logistic regression was used to determine factors associated with skeletal muscle mass index (SMI). RESULTS: Of the total 119 participants, 47 were Japanese (26 men, 21 women) and 72 were Thai (16 men, 56 women). The prevalence of a low SMI was 3/26 (12%), 1/21 (5%), 6/16 (38%), and 5/56 (9%) among Japanese men, Japanese women, Thai men, and Thai women, respectively. The prevalence of low muscle strength was 2/26 (8%), 2/21 (10%), 3/16 (19%), and 13/56 (23%) among Japanese men, Japanese women, Thai men, and Thai women, respectively. There were significant differences between ethnic groups in body mass index for both sexes, percentage body fat in women, SMI in men, and average grip strength in men. Ethnic group, sex, age, and body mass index were independent predictors of SMI. CONCLUSIONS Ethnicity had a clinically important effect on body composition and physical strength among older Japanese and Thai adults living in a similar environment.
Aged ; Aging/physiology* ; Asians/ethnology* ; Body Composition ; Body Mass Index ; Cross-Sectional Studies ; Electric Impedance ; Ethnicity ; Female ; Hand Strength ; Humans ; Independent Living ; Male ; Middle Aged ; Muscle Strength ; Thailand/ethnology* ; Walking Speed