The adverse events of this study will be recorded using a dedicated form (time, location, first aid treatment, causal analysis, follow-up). Adverse events are recorded throughout the entire experimental process. The less adverse events descriptions there will be, the better the feasibility

Participants crossed their arms across their chest and performed the complete movement of 'fully lifting their back off the chair back → standing straight → sitting back down' as many times as possible within 30 seconds. The counting standard was that the next standing movement could only begin after the buttocks made contact with the chair seat. The assessment criteria are as follows for the 50-59 age group: males (poor: <15 times, moderate: 15-20 times, good: >20 times); for females (poor: <13 times, moderate: 13-18 times, good: >18 times). Two assessment points, from "baseline" to "immediately after the completion" (no follow-up, intervention duration-4 weeks)

Participants stand with both feet on the middle section of the resistance band (the stength of resistance band is 20 pounds in this study), holding the band with both hands and securing it at shoulder level. Within 30 seconds, they perform as many full-range squats as possible (with thighs below the horizontal line), maintaining a straight back and knees aligned with the toes throughout the movement. The number of repetitions directly reflects lower limb muscle strength and dynamic stability, with a higher number indicating stronger functional strength. For individuals aged 50 to 60, males with fewer than 10 repetitions are considered weak, 10-14 repetitions are moderate, and 15 or more are strong; females with fewer than 8 repetitions are considered weak, 8-12 repetitions are moderate, and 13 or more are strong.Two assessment points, from "baseline" to "immediately after the completion" (no follow-up, intervention duration-4 weeks)

Participants sit on the ground with legs straightened and heels together against the test box. Arms are extended forward, and the slider is slowly pushed to the farthest distance and held for 1 second. The position reached by the fingertips is measured (the sole of the foot is 0 points; values exceeding this are positive, and values not exceeding it are negative). The measurement value (in centimetres) reflects the flexibility of the lower back and hamstrings. A higher positive value indicates better flexibility (e.g., >+15 cm is excellent), while a negative value suggests stiffness and the need for stretching (e.g., <-5 cm indicates a risk of strain).Two assessment points, from "baseline" to "immediately after the completion" (no follow-up, intervention duration-4 weeks)

Participant stands upright with one arm extended forward. Without moving the feet, the maximum horizontal distance that the fingertips can be extended forward is measured (unit: centimetres). The distance value reflects dynamic balance ability. A forward extension distance of <15.2 cm indicates a significantly increased risk of falling (sensitivity 89%, specificity 79%), while healthy elderly people typically have a distance of ≥25 cm.Two assessment points, from "baseline" to "immediately after the completion" (no follow-up, intervention duration-4 weeks)

Participants walked back and forth at their fastest pace on a 30-metre flat corridor for 6 minutes. The operator reported the time every minute and provided standardised encouragement (e.g., 'Keep going, only X minutes left'). Total walking distance (metres) directly reflects cardiopulmonary function and overall endurance. Healthy adults typically achieve 400-700 metres; a distance of <300 metres suggests severe heart failure or significantly increased risk of falls, while an increase of ≥70 metres indicates effective rehabilitation therapy.Two assessment points, from "baseline" to "immediately after the completion" (no follow-up, intervention duration-4 weeks)

Participants stand up from a chair with armrests, walk 3 metres at their usual pace, turn around, and return to sit down again. The entire process is timed (in seconds), and the use of conventional walking aids is permitted. The completion time directly reflects dynamic balance and fall risk. A time of ≥12 seconds indicates a significantly increased risk of falling (community elderly threshold value). Specific thresholds should be adjusted based on the population (e.g., ≥11.5 seconds for Parkinson's disease patients, ≥10 seconds for hip arthritis patients).Two assessment points, from "baseline" to "immediately after the completion" (no follow-up, intervention duration-4 weeks)

Participants stand on one leg with their eyes open (they may choose to place their hands on their hips or let them hang naturally), with the other leg bent and lifted off the ground. The maximum time spent maintaining balance is recorded (in seconds). The testing process must be conducted with full fall prevention measures in place. Standing time reflects static balance ability. Healthy adults typically achieve ≥30 seconds (for the 30-year-old population), while <10 seconds indicates a significantly increased risk of falls (a sensitive indicator for the elderly). Specific results should be interpreted in conjunction with age-specific standards (e.g., ≥15 seconds is considered normal for those aged 60 years). Two assessment points, from "baseline" to "immediately after the completion" (no follow-up, intervention duration-4 weeks)

Participants completed multiple cognitive domain tests included in this scale (including memory, visuospatial, executive function, attention, language, etc.), covering tasks such as alternating line drawing, cube copying, clock drawing, word recall, calculation, and orientation. The total score of the scale is 30 points. A score of ≥26 points (or ≥25 points after adjustment) indicates normal cognitive function, while a score of ≤22 points suggests mild cognitive impairment (MCI). Two assessment points, from "baseline" to "immediately after the completion" (no follow-up, intervention duration-4 weeks)

Participants answered nine questions about the frequency of recent declines in memory using a self-report questionnaire. Each question was scored using a two-category option (yes = 1 point, no = 0 points) or a three-category option (often = 1 point, occasionally = 0.5 points, never = 0 points). A higher total score indicates more significant subjective cognitive decline, and participants with a total score of ≥5 were identified as having subjective cognitive decline.Two assessment points, from "baseline" to "immediately after the completion" (no follow-up, intervention duration-4 weeks)

"The COGNITIVE EXPERIMENTS STANDARD TOOLBOX" is an online cognitive testing platform. Users load standardised cognitive testing tasks (such as executive function, working memory, etc.) via the online platform or local programme and complete an adaptive experimental process (including practice and formal testing) according to the on-screen prompts. The system automatically generates cognitive ability scores based on comprehensive indicators such as accuracy and reaction time. Two assessment points, from "baseline" to "immediately after the completion" (no follow-up, intervention duration-4 weeks)

The exergame developed for this study (a total of eight sections, each divided into beginner and advanced games) are designed to train participants' various cognitive functions (including memory, attention, and executive function). The games automatically record participants' response times and scores for each section. The total score for each section (beginner or advanced) ranges from 0 to 50 points, with higher scores being better.Two assessment points, from "baseline" to "immediately after the completion" (no follow-up, intervention duration-4 weeks)