The main objective was to assess the feasibility of an intensive rehabilitation program (IRP) for stroke patients; and secondly, to detect eventual age-related differences in content, duration, tolerability, and safety in a prospective observational cohort of patients diagnosed with subacute stroke, admitted to inpatient rehabilitation (BRAIN-CONNECTS project). Activities during physical, occupational and speech therapy, and time dedicated to each one were recorded. Forty-five subjects (63.0 years, 77.8% men) were included. The mean time of therapy was 173.8 (SD 31.5) minutes per day. The only age-related differences when comparing patients ≥65 and <65 years were a shorter time allocated for occupational therapy (−7.5 min (95% CI −12.5 to −2.6), p = 0.004) and a greater need of speech therapy (90% vs. 44%) in the older adults. Gait training, movement patterns of upper limbs, and lingual praxis were the most commonly performed activities. Regarding tolerability and safety, there were no losses to follow-up, and the attendance ratio was above 95%. No adverse events occurred during any session in all patients. Conclusion: IRP is a feasible intervention in patients with subacute stroke, regardless of age, and there are no relevant differences on content or duration of therapy.