Examining the Health Impact of and Promoting Sitting Light Volleyball in the Greater Bay Area

One hundred and thirty-eight participants will be randomly assigned into the SLVB, Seated Dance (SD), and control groups in a 1:1:1 ratio. Outcome assessors will be blinded to treatment allocation. Data will be collected at baseline (pretest), after a 16-week intervention (posttest), at 3 months and 6 months after the intervention. Both the SLVB and SD intervention programmes consist of 32 training sessions, with 2 x 75- min sessions per week. The duration of the proposed intervention is consistent with the recommendation of World health Organization. The SLVB intervention programme will be based on our previous SLVB programme specifically designed for PWPD. Programme content will include SLVB basic skills and posture, basic team tactics, and rules and regulations. In the SD group, participants will learn freestyle para dance in sessions, including hip-hop and Latin dance. They will learn step sequences of increasing complexity in a seated position, and music will then be added. Participants in the control group will be instructed to maintain their normal daily activity and asked to join monthly non-exercise social gatherings (e.g., health talk) to balance the psychosocial effect of the regular gatherings in other groups. Inclusive criteria for participants will be (a) aged ≥18 years; (b) PWD registered in the Central Registry for Rehabilitation; (c) diagnosed with physical disabilities such as impaired muscle power, limb deficiency, or leg length difference, using the SVB and Para dance classification of International Paralympic Committee; (d) with at least one functional arm; (e) with a normal to mild grade intellectual disability; (f) have not participated in a structured PA programme during the 6 months preceding the study; and (g) can communicate in Chinese. The Mini-Mental Statewill be used to screen for abnormal cognitive function; the Berg Balance Scale will be used to screen for participant's sitting balance ability. Participants who a) record an MMSE score ≤ 17; b) are unable to sit unsupported [balance score ≤ 2 (i.e., sit 30 seconds)]; c) Body Mass index (BMI) ≥ 27; d) have had orthopaedic surgery 6 months prior to the study entry; e) have a history of cardiovascular disease that hinders study participation; f) have seeing and/or hearing difficulties; g) have not been approved by his/her physician to participate in the study due to a limiting medical condition, will be excluded from the study. Based on a more conservation effect size (Cohen's d = .6) from the physical attributes of our previous SLVB intervention study, a total sample of 111 PWPD (with 20% expected dropout rate) is required in this study to achieve power of 80% at p ≤ .05. The investigators, therefore, aim to recruit a total sample size of 138 participants (46 participants per NGO serving PWPD, 3 NGOs are needed) and allocated in a 1:1:1 ratio into SLVB, SD and control groups (15-16 participants in each arm in each NGO). Procedures. Participants will be recruited through recruitment talk(s) conducted by the research team and by advertisements in the partnered NGOs. First, an initial information session will be delivered to groups of potential participants by providing them with intervention details and distributing the informed consent statement. After obtaining the participant's signed informed consent, data collection will be conducted by the SRA and trained student helpers. Before the pretest, participants will undergo screening tests such as MMSE. In addition to completing questionnaires, participants will begin by taking fitness and other tests according to the standardized testing protocol. Next, an independent researcher, not otherwise involved in the study, will use a computer-based random number generator to randomly assign participants into SLVB, SD, or control groups. The intervention will begin next week. Participants will complete a posttest and follow-up tests upon completion of the 16-week intervention, 3 and 6 months after the intervention, respectively, using procedures identical to those described for the pretest measurements. The independent evaluators assessing the participants' outcomes and individuals performing data entry and data analysis will be blinded to group assignment.

Measures (Primary - Physical health outcomes) i. Physical fitness. The Brockport physical fitness test will be used to measure the physical fitness of participants. The fitness tests include a grip test (upper body muscular strength), dumbbell press test (upper body muscular endurance), skinfold test and body mass index evaluation (body composition), and shoulder stretch test (flexibility). Submaximal arm ergometry test, six-Minute Arm Test will be used to measure participant's aerobic endurance. The validity and reliability of the above tests have been confirmed for use with PWD and it has been used in HK.

ii. Sitting balance. A modified Functional Reach Test will be used to assess limits of stability by measuring the maximum distance that an individual can reach forward and laterally while sitting in a fixed position. Its reliability and validity have been supported for adults with disabilities.

iii. Anticipation time. A Bassin Anticipation Timer (BAT, Lafayette Instrument Company, Model 35575) will measure the participant's visual acuity related to eye-hand coordination and anticipation (in milliseconds.). Using BAT devices, participants will be instructed to press a button to coincide with light arrival at the target.

Measures (Secondary - Psychological health outcomes) i. Quality of life (QoL). QoL will be measured using a shortened version of the SF36 Health Survey (SF-12). Reliability and validity have been evaluated in Chinese. SF-12 comprises eight domains such as mental health, social, and physical functioning …etc.

ii. PA enjoyment. A short version of the Physical Activity Enjoyment Scale (PACES) in Chinese will be used to measure PA enjoyment in the study. Other studies have also validated the psychometric properties of this 8-item PACES.

ii. Mindful self-care. Mindful Self-Care Scale - Chinese Version (24 item) measures an individual's level of mindful self-care across various dimensions, including physical care, supportive relationships, mindful awareness, self-compassion and purpose, mindful relaxation, and supportive structure.

Data analysis. Intent-to-treat sample will be used in the primary analysis. The Generalized Estimating Equation (GEE) model will be used to test the statistical significance of the mean changes in the primary and secondary outcomes among the three groups. Adjustments will be performed for the age and gender of the participants. The GEE model handles the auto-correlations among the repeated measurements within a participant in each group, as well as non-normal data, and accommodates missing data points across the measurement time points. The same statistical analysis will be performed in the per-protocol sample as a secondary analysis. A dose-response analysis will be conducted by treating adherence to the intervention as an independent variable. Data will be analyzed using SPSS 27.0 with a significance level set at .05 Qualitative study is used to determine the barriers and facilitators of the intervention implementation from the perspective of stakeholders, thirty participants in the SLVB group will be recruited using purposive sampling, stratified by gender and completion of our intervention. Intervention completion is defined as an attendance rate of 80% or higher. Next, 6 administrators and 6 coaches will also be invited to participate in the interview. This sample size is referenced to a similar study using the Consolidated Framework for Implementation Research (CFIR) in PWD, qualitative research meta-synthesis in PWPD's PA and our previous SLVB qualitative studies. Procedures. Participants (group of five for participants, group of two for administrators, group of two for coaches) in the SLVB group will be invited to join this qualitative arm. It is guided by our SLVB qualitative studies and the CRIF, which provides 39 constructs housed in 5 domains such as intervention characteristics, and implementation process. CFIR will guide this study's data collection, analysis and reporting.

In terms of data analysis, all interviews will be transcribed verbatim and coded using QSR-NVivo. Using thematic analysis, data will be organized into themes based on CFIR. Two independent coders will read, re-read, and code the interview transcripts to ensure that coding is done following the CFIR coding guide. Finally, coded transcripts will be compared, followed by another discussion with the coders and investigators to facilitate further the development of themes related to the framework. The 32-point consolidated criteria for reporting qualitative studies will be used to report the result.