Abstract
BACKGROUND: Spinal cord injury (SCI) is associated with significant impairment in mobility, muscular strength, and aerobic capacity. Inpatient rehabilitation protocols may not consistently include structured group-based physical training. The structured group-based therapeutic exercise program was designed to address this gap through a supervised therapeutic exercise circuit adapted to the patient’s functional status. OBJECTIVE: To evaluate the effectiveness and feasibility of a 12-week group-based therapeutic exercise program on muscular strength, aerobic capacity, adherence, and satisfaction in hospitalized patients with spinal cord injury (SCI). METHODS: A quasi-experimental, single-group pre–post study was conducted in the Neurorehabilitation Unit of Miguel Servet University Hospital (Zaragoza, Spain). Fifty-seven adults with SCI below C3 level were included. Both complete and incomplete cases (AIS A–D) were considered eligible for inclusion. Patients were grouped based on their trunk control ability (seated or standing). The intervention included aerobic and strength training sessions (five days/week). Outcome measures included muscular strength (Medical Research Council Scale), aerobic capacity [6-Minute Walk Test (6MWT) for ambulatory participants or 6-Minute Push Test (6MPT) for wheelchair users], and feasibility (adherence/attendance, patient satisfaction, and safety). Statistical analysis was performed using regression models informed by a directed acyclic graph (DAG), including linear and generalized additive models with permutation-based robustness checks. RESULTS: Post-intervention improvements were observed in upper-limb strength (mean difference + 3.7 points, 95% CI 2.5–4.9; Cohen’s d = 0.62) and 6MWT/6MPT distance (mean difference: +87.5 m, 95% CI 68–108; Cohen’s d = 0.55). The effects were more pronounced in participants with AIS C injuries of infectious–vascular origin and in ensure proper sentence structure. Most pre-treatment values did not show a direct association with post-intervention outcomes, suggesting minimal confounding factors. Median attendance was high (39/60 planned sessions; IQR values), satisfaction scores were high overall, no adverse events occurred, and equipment adequacy ratings were lower in non-ambulatory participants. CONCLUSIONS: A supervised, stratified group-based program was feasible and acceptable during inpatient SCI rehabilitation and associated with improvements in muscular strength and aerobic capacity. Given the single-group design and concurrent routine care, these findings were preliminary. Multicenter randomized trials, stratified by AIS and time since injury and incorporating pre-specified feasibility endpoints (safety, adherence, therapist time, satisfaction, and resource use), are warranted to confirm efficacy and evaluate durability and cost-effectiveness. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12984-025-01845-z.