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BACKGROUND AND RATIONALE Spinal cord injury (SCI) is associated with numerous secondary health conditions that can adversely affect physical health, mental health, and health-related quality of life (HRQoL). Insufficient exercise participation, sedentary behavior, and inadequate nutrition may contribute to the development or progression of these conditions. Adults aging with SCI may face additional health challenges resulting from the combined effects of SCI and aging, including cardiometabolic disease, reduced physical fitness, functional decline, changes in body composition, poor mental health, and reduced HRQoL. Exercise represents an important non-pharmacological strategy for promoting health among people with SCI (PwSCI). Previous exercise interventions involving PwSCI have demonstrated improvements in cardiorespiratory fitness and muscular strength, as well as beneficial effects on subjective, psychological, and social well-being and HRQoL. However, adults aging with SCI have been underrepresented in exercise intervention research. Exercise participation also remains low in this population, highlighting the need to identify feasible strategies for supporting sustained engagement in exercise. Nutrition represents another important but comparatively understudied component of health following SCI. PwSCI may experience reduced energy requirements while also demonstrating dietary patterns characterized by inadequate intake of fruits, vegetables, protein, dairy, whole grains, and other essential nutrients. SCI-related changes in appetite regulation, eating behaviors, functional ability, food preparation, and access to appropriate nutrition information may further contribute to challenges in maintaining healthy eating behaviors. Despite increasing recognition of the importance of nutrition following SCI, evidence from randomized controlled trials (RCTs) of nutrition interventions remains limited. Exercise and healthy eating may also be influenced by multiple individual, social, and environmental barriers. Physical limitations, inaccessible environments, limited availability of adapted exercise equipment, and insufficient knowledge regarding appropriate exercise and nutrition strategies have been identified as potential barriers among PwSCI. These challenges support the development of multicomponent interventions that address exercise and nutrition while incorporating behavioral strategies to facilitate engagement and adherence. STUDY PURPOSE The purpose of this study is to conduct a pilot RCT evaluating the feasibility, fidelity, acceptability, and usability of a combined exercise and nutrition education intervention for adults aged 50 years and older living with SCI. The pilot trial is intended to inform the design and conduct of a future fully powered hybrid type II effectiveness-implementation pragmatic RCT. The primary focus of the pilot trial is therefore not to establish definitive intervention effectiveness. Instead, the study will determine whether the intervention and associated research procedures can be successfully implemented, whether participants engage with and complete the intervention, whether the intervention can be delivered with adequate fidelity, and whether participants perceive the intervention and study procedures as acceptable and usable. The investigators hypothesize that the combined intervention and associated study procedures will demonstrate high feasibility, acceptability, and usability. Information obtained from this pilot trial will be used to determine whether progression to a larger trial is warranted and to identify modifications that should be made before conducting a fully powered RCT. INNOVATIVE AND PRAGMATIC APPROACH The study integrates exercise training, nutrition education, and theory-informed behavioral counseling within a single intervention. This multicomponent approach is intended to address several factors that may influence healthy lifestyle behaviors among adults aging with SCI rather than focusing on exercise or nutrition in isolation. The study adopts a pragmatic approach intended to increase the relevance of the intervention to real-world settings. The intervention was designed using the Acceptability, Practicability, Effectiveness, Affordability, Side-effects, and Equity (APEASE) criteria. Pragmatism was also considered using the PRagmatic Explanatory Continuum Indicator Summary (PRECIS-2). Consistent with this pragmatic approach, the nutrition component focuses on nutrition education rather than prescribing a standardized dietary regimen. The goal is to provide participants with knowledge and strategies that can be applied to food choices and eating behaviors in daily life. Similarly, aspects of the intervention allow flexibility in how and where certain components are completed, while supervised strength training is provided in a fully accessible exercise facility. THEORETICAL FRAMEWORK The intervention is informed by the Behavior Change Wheel (BCW) and its underlying Capability, Opportunity, and Motivation-Behavior (COM-B) model. The COM-B model proposes that behavior is influenced by an individual's capability, opportunity, and motivation to perform that behavior. Behavior change techniques incorporated into the intervention include demonstration of behavior, feedback on behavior, self-monitoring, information regarding health consequences, instruction on how to perform a behavior, goal setting, action planning, restructuring of the physical environment, use of credible sources, and feedback on behavioral outcomes. These strategies are incorporated across the exercise, nutrition education, and behavioral counseling components. For example, participants receive instruction and demonstration regarding exercise performance, feedback on exercise form and technique, opportunities to establish exercise and healthy eating goals, and support for developing weekly action plans. Participants are also encouraged to self-monitor adherence and receive feedback intended to support continued participation. Access to a fully adapted exercise facility provides environmental opportunity for participation in exercise. STUDY DESIGN AND RANDOMIZATION This study is a two-arm, assessor-blinded, pragmatic Stage I pilot RCT. Participants will be randomized in a 1:1 ratio to either: 1. A 16-week combined exercise, nutrition education, and behavioral counseling intervention; or 2. A waitlist control condition, with participants subsequently receiving the intervention following the initial 16-week control period. A computer-generated randomization schedule will be used. Randomization will use permuted blocks of varying sizes to support allocation concealment and will be stratified by sex. The randomization sequence will be generated and maintained by a research assistant who is not involved in participant enrollment or outcome assessment. Group assignments will be maintained in a secure database and revealed only after completion of baseline assessments. Outcome assessors will remain blinded to participant group assignment when applicable. PARTICIPANTS AND RECRUITMENT The study will recruit adults aged 50 years and older living with chronic SCI. Recruitment strategies will include word of mouth; distribution of Institutional Review Board (IRB)-approved recruitment materials, including posters, flyers, and electronic materials; advertisements through Wayne State University social media channels; and outreach to rehabilitation facilities and local and national SCI organizations. Participants must have sustained an SCI at least 12 months before enrollment, must not currently meet the SCI Exercise Guidelines, and must receive physician clearance to participate in the trial and complete peak exercise testing. Exclusion criteria are intended primarily to promote participant safety and ensure that individuals can feasibly participate in the intervention. These include SCI involving the first three cervical vertebrae when this would interfere with independent respiratory control, insufficient upper-extremity motor function to perform the prescribed exercises, a diagnosis of cognitive impairment, and current residence in an inpatient or rehabilitation facility. INTERVENTION Participants assigned to the intervention will complete a 16-week multicomponent intervention consisting of individualized exercise training, weekly nutrition education, and weekly behavioral counseling. Exercise Training Participants will receive an individually tailored exercise prescription from a certified fitness trainer based on the SCI Exercise Guidelines. As a starting prescription, participants will be asked to perform strength training for each major functioning muscle group at least twice per week and at least 20 minutes of aerobic exercise twice per week. Strength training will include three sets of 10 repetitions for each major functioning muscle group and will be completed using accessible HUR exercise equipment under the supervision of certified fitness trainers. To maximize pragmatism and accommodate participant preferences, aerobic exercise may be completed independently at the study gym or at another location selected by the participant, such as at home or outdoors, as appropriate. Nutrition Education Participants will receive one approximately 30-minute nutrition education session each week throughout the 16-week intervention. Nutrition education will be delivered by qualified study personnel with relevant training in nutrition and food science and with oversight from the study investigators. The 16 educational modules will address: Week 1: Guide to Healthy Eating Week 2: The Fruit Group Week 3: The Vegetable Group Week 4: The Grain Group Week 5: The Protein Group Week 6: Meat or Meat Alternatives Week 7: The Dairy Group Week 8: Fat Week 9: Essential Fatty Acids Week 10: Ways to Eat Less Saturated Fat and Reduce Energy Intake Week 11: Carbohydrates Week 12: Fiber Week 13: Planning a Healthy Meal Week 14: Building a "Light" Meal Week 15: Healthy Satisfying Snacks Week 16: Reading the Nutrition Facts Label The nutrition component emphasizes education rather than prescription of a specific diet, consistent with the pragmatic nature of the trial. Behavioral Counseling Participants will receive approximately 15 minutes of behavioral counseling each week with a trained behavioral coach. Counseling will incorporate theory-informed behavioral strategies designed to support adherence to exercise and healthy eating behaviors. Participants will also report adherence to independently completed intervention activities during these sessions. Participants may choose to receive nutrition education and behavioral counseling either in person or virtually, providing flexibility in intervention delivery. SPECIFIC AIM 1: PROCESS FEASIBILITY The first aim will determine the feasibility of intervention and trial processes. Primary process feasibility outcomes will include recruitment, retention, and adherence. Recruitment feasibility will be evaluated based on the ability to recruit the target sample within the planned recruitment period. Retention will represent the proportion of enrolled participants who remain in the study through the relevant follow-up assessment. Adherence will be evaluated separately for exercise training, nutrition education, and behavioral counseling. Progression criteria will be interpreted using a traffic-light framework consisting of "progress," "amend and progress," and "do not progress" categories. The planned progression benchmarks include: * Recruitment of 24 participants within 12 months; * Retention of at least 90%; * Exercise session adherence of at least 85%; * Nutrition education session adherence of at least 90%; and * Behavioral counseling session adherence of at least 90%. Feasibility outcomes falling below these benchmarks will be evaluated according to predefined amend-and-progress and do-not-progress criteria. Because feasibility estimates are subject to uncertainty and chance variation in small pilot samples, progression decisions will not be determined solely by numerical thresholds. The research team will consider the totality of the feasibility findings and use consensus-based pragmatic decision-making when determining whether modifications are required and whether progression to a full-scale trial is warranted. Feasibility outcomes will be summarized descriptively using means, counts, percentages, and 95% confidence intervals, as appropriate. SPECIFIC AIM 2: SCIENTIFIC FEASIBILITY AND OUTCOME ASSESSMENT The second aim will evaluate scientific feasibility, including the feasibility of outcome assessment, data collection and storage procedures, and the identification of major safety concerns that could affect progression to a future trial. The clinical and patient-reported measures included in the pilot trial are intended primarily to evaluate the feasibility and acceptability of conducting these assessments in a future full-scale RCT rather than to provide definitive evidence of intervention efficacy or effectiveness. Physical health outcomes will include muscular strength, cardiorespiratory fitness, moderate-to-vigorous physical activity, metabolic health, and pain. Muscular strength will be estimated using one-repetition maximum assessments for the bench press and seated row using HUR exercise equipment. Cardiorespiratory fitness will be assessed by maximal oxygen consumption (VO2max) using a progressive arm-crank exercise test with metabolic measurement. Moderate-to-vigorous physical activity will be assessed using the Leisure-Time Physical Activity Questionnaire for People with SCI (LTPAQ-SCI). Metabolic health will be evaluated using blood-based cardiometabolic biomarkers, including hemoglobin A1c, glucose, insulin, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides. Pain will be evaluated using the International SCI Pain Basic Data Set Version 3.0. Nutrition-related outcomes will include nutrition knowledge and nutrition self-efficacy. Nutrition knowledge will be assessed using a nutrition knowledge questionnaire developed for PwSCI, and self-efficacy will be assessed using the Physical Activity and Nutrition Self-Efficacy measure. Mental health and HRQoL assessments will examine multiple dimensions of well-being, including subjective well-being, psychological well-being, social well-being, and HRQoL. Measures include the Satisfaction with Life Scale, Depression and Anxiety subdomains from the SCI-QoL-short forms, Achievement and Progress item from the ICECAP-A, Resilience subdomain from the SCI-QoL-short form, Satisfaction with Social Roles and Activities from SCI-QOL, and SCI-QOL measures, and Measure of Experiential Aspects of Participation. The progressive arm-crank test and muscular strength assessments will be conducted under appropriate supervision using procedures established by the research team. Participants will also undergo venous blood collection for the assessment of glycemic and cardiometabolic biomarkers. Although the pilot RCT is not designed or powered to establish between-group effectiveness, exploratory analyses of clinical outcomes will be conducted to inform the design of a future trial. Linear mixed-effects models will be used for each clinical outcome following the intention-to-treat principle. Point estimates will be presented with 95% confidence intervals, and data will also be presented disaggregated by sex/gender. ADVERSE EVENT MONITORING The study will evaluate whether any major safety concerns emerge that would affect progression to a larger RCT. Adverse events will be defined and classified according to established National Institute on Aging guidance. Events will be distinguished as adverse events or serious adverse events and categorized according to severity, expectedness, and relatedness to study participation by the study physician. Safety findings will be interpreted in the context of the pilot design. The study is not intended to establish definitive intervention safety but will determine whether major safety concerns are identified that would require modification of the intervention or study procedures before progression to a larger trial. SPECIFIC AIM 3: RESOURCE, MANAGEMENT, AND INTERVENTION FIDELITY The third aim will determine resource and management feasibility and evaluate intervention fidelity. Fidelity assessment will be informed by the National Institutes of Health Fidelity Framework and methodological recommendations for exercise intervention studies involving PwSCI. Fidelity will include evaluation of intervention receipt and intervention delivery. Exercise receipt will be evaluated using information obtained from the HUR exercise equipment for strength training and participant self-report for aerobic training. These data will be used to determine the extent to which participants performed the prescribed exercise at the intended frequency, intensity, and duration. Intervention delivery will be evaluated by an independent observer using standardized checklists applied to a randomly selected sample of intervention sessions. Exercise sessions will be evaluated through in-person observation, while selected nutrition education and behavioral counseling sessions will be evaluated using session recordings. Fidelity assessment will examine whether exercise, nutrition education, and behavioral counseling are delivered according to the study protocol and intervention manual. Assessment will also consider differentiation from non-study treatments and the competence with which intervention components are delivered, including tailoring, appropriate adaptations, participant engagement, interactive communication, and constructive feedback. Resource and management feasibility will include documentation of equipment requirements and utilization, personnel training requirements, time and resources required for intervention delivery, assessment procedures, and data management processes. Data management feasibility will include evaluation of procedures for data collection, anonymization, storage, entry, and analysis. ACCEPTABILITY AND USABILITY Participants' perceptions of the intervention will be evaluated using Likert-type scales. Areas of evaluation will include perceived usefulness, ease of exercise participation, satisfaction with the exercise prescription, satisfaction with nutrition education, satisfaction with behavioral counseling, and satisfaction with study personnel. These measures will provide information regarding how participants experience the intervention and whether modifications are needed to improve its acceptability and usability before a full-scale trial. SPECIFIC AIM 4: PARTICIPANT EXPERIENCES AND PERSPECTIVES The fourth aim will explore participants' experiences, perspectives, and preferences related to the intervention and study procedures. All participants will be invited to participate in semi-structured interviews examining perceived barriers and facilitators to participation, experiences with the intervention components, and perspectives regarding study procedures. The interviews will provide qualitative information that cannot be fully captured through quantitative feasibility and acceptability measures. Interview data will undergo thematic analysis. Themes will be deductively mapped to the COM-B model and APEASE criteria, while inductive coding will allow additional themes to emerge directly from participants' experiences. Integrating deductive and inductive qualitative approaches will allow the investigators to identify intervention components or study procedures that should be retained, modified, or adapted before progression to a future trial. Participant perspectives will therefore be considered alongside quantitative feasibility, fidelity, acceptability, usability, resource, management, and safety findings when determining the next stage of the research program. OVERALL STUDY OBJECTIVE This pilot trial is designed to determine whether a multicomponent exercise, nutrition education, and behavioral counseling intervention can be feasibly and acceptably implemented among adults aged 50 years and older living with SCI. By simultaneously evaluating process feasibility, scientific feasibility, intervention fidelity, resource and management requirements, acceptability, usability, and participant perspectives, the study will provide the information necessary to refine both the intervention and research procedures. The combination of quantitative feasibility metrics and qualitative participant feedback will allow the investigators to determine not only whether progression to a larger trial is appropriate, but also what modifications may be necessary to optimize future implementation. Ultimately, findings from this pilot RCT will inform the design of a fully powered hybrid type II effectiveness-implementation pragmatic RCT evaluating both the effectiveness and implementation of a combined exercise and nutrition education intervention for adults aging with SCI.