Moderate-Intensity Aerobic Calisthenics for Rural Elderly With Motoric Cognitive Risk Syndrome

The SCD-Q9 was adapted and revised into Chinese by Hao Lixiao et al. It encompasses two dimensions: global memory ability with time comparison, and activities of daily living. It primarily assesses memory, recall ability, language ability, attention, orientation, and other domains. The questionnaire consists of 9 items. The scoring reference criteria for item responses are as follows: "Yes" = 1 point, "No" = 0 points, "Often" = 1 point, "Occasionally" = 0.5 points. The total score ranges from 0 to 9 points, with higher scores indicating a greater likelihood of cognitive impairment. A score of ≥5 points suggests the possible presence of potential memory impairment.

The Short Physical Performance Battery (SPPB), developed by the National Institute on Aging (NIH), objectively assesses balance, lower limb strength, and physical function in older adults. Originally designed to predict disability, institutionalization, or mortality, it is now widely used for frailty, fall risk, and disease-related functional impairment. The SPPB includes three tests: balance, 4-meter gait speed, and five-repetition sit-to-stand, each scored 0-4, total 0-12 (higher = better function). Scores 0-3: severe mobility limitation with daily living difficulties; 4-6: mild limitation, needing assistance or aids; 7-9: normal mobility, independent in daily activities; 10-12: excellent mobility, robust and strong.

A electronic hand dynamometer (CAMRY, USA) was used to assess the upper limb muscle strength of the participants. Before measurement, the staff adjusted the dynamometer to zero. During the test, the participant stood in a natural posture with both arms hanging naturally at the sides. The dynamometer was kept as suspended as possible without touching the body, while maintaining the device stable. The participant was instructed to relax and then squeeze the dynamometer forcefully with the dominant hand three times (with an interval of >15 seconds between each attempt). The maximum value among the three attempts was recorded as the grip strength.

Body composition was assessed using bioelectrical impedance analysis (BIA) with an InBody H20N body fat scale, primarily measuring muscle and fat-related parameters. Before testing, participants wore light clothing without metal accessories and removed metal items such as watches, rings, and necklaces. During testing, participants stood barefoot on the metal electrode plates with feet shoulder-width apart, ensuring close contact of heels and forefeet with the plates. They held the handles on both sides with arms hanging naturally, hands dry and not touching the trunk. The operator initiated the measurement, during which participants remained still, silent, and motionless. The measurement lasted 1-2 minutes, and the device introduced a low-intensity electrical current to determine bioelectrical impedance parameters and estimate body composition.

The SF-12, a shortened version of the 36-Item Short-Form Health Survey (SF-36), assesses health-related quality of life. It retains the eight dimensions of the SF-36 with 12 items, covering general health (GH), physical functioning (PF), role physical (RP), bodily pain (BP), role emotional (RE), mental health (MH), vitality (VT), and social functioning (SF). The first four dimensions evaluate physical component summary (PCS), and the latter four evaluate mental component summary (MCS). The total score ranges from 0 to 100, with higher scores indicating better quality of life. Xiao Huimin et al. demonstrated good reliability and validity of the SF-12 among Chinese older adults.

The 9-item Patient Health Questionnaire (PHQ-9) assesses depressive symptom severity over the past two weeks. Each item is rated on a 4-point scale (0 = not at all, 1 = several days, 2 = more than half the days, 3 = nearly every day), with a total score ranging from 0 to 27 (higher scores indicate greater depression severity). Cutoff scores: 0-4 = no depression; 5-9 = possible mild depression; 10-14 = moderate depression risk; ≥15 = severe depressive symptoms. The scale has good internal consistency (Cronbach's α = 0.894).

The 7-item Generalized Anxiety Disorder scale (GAD-7) assesses the severity of anxiety symptoms over the past two weeks. Each item is rated on a 4-point scale (0 = not at all, 1 = several days, 2 = more than half the days, 3 = nearly every day), with a total score ranging from 0 to 21 (higher scores indicate greater anxiety severity). Cutoff scores: 0-4 = no anxiety; 5-9 = mild anxiety; 10-14 = moderate anxiety; ≥15 = severe anxiety. The scale has good internal consistency (Cronbach's α = 0.840) and demonstrates good reliability and validity in the Chinese population.

The WHO-5 Well-Being Index, developed by Bech and revised by the WHO Collaborating Centre for Research in Mental Health, assesses subjective well-being over the past two weeks. The scale consists of 5 items, each rated on a 6-point scale (0 = none, 1 = a little of the time, 2 = less than half the time, 3 = more than half the time, 4 = most of the time, 5 = all the time). The raw sum is multiplied by 4 to obtain a standardized total score ranging from 0 to 100, with higher scores indicating better well-being. The scale has good internal consistency (Cronbach's α = 0.86) . A score below 50 indicates reduced well-being [144]. In this study, well-being is categorized as high (≥70), moderate (50-70), and low (≤50).

The Theory of Planned Behavior Questionnaire, developed by Icek Ajzen, consists of 12 items across four dimensions: behavioral attitude, subjective norm, perceived behavioral control, and behavioral intention. It is used to measure the social cognitive variables of the theory of planned behavior. The target behavior in this questionnaire refers to the exercise goal set for rural older adults with Motor Cognitive Risk Syndrome (i.e., participating in at least 150 minutes of moderate-intensity aerobic exercise per week). Items are rated on a 7-point Likert scale, ranging from "strongly disagree" to "strongly agree," with scores from 1 to 7. Higher scores indicate greater levels of agreement.