Subacute and inpatient rehab: dose, intensity, and the plasticity window

1. Case. A 57-year-old man with a right pontine infarct arrives at the inpatient rehabilitation facility on day 8. Left hemiparesis. He can sit unsupported, transfers with moderate assist of one, and ambulates 15 m with a hemi-walker and moderate assist. Berg 18/56.

2. CPG section. AHA/ASA 2016 recommends rehabilitation in an inpatient rehabilitation facility over a skilled nursing facility when the patient qualifies (Class I, Level B). Three hours of skilled rehabilitation per day, five days per week, is the IRF coverage standard. Kleim and Jones's 10 principles of experience-dependent neural plasticity (Kleim JA, Jones TA. *J Speech Lang Hear Res*. 2008;51:S225–S239) frame the dose conversation: use it or lose it, use it and improve it, specificity, repetition, intensity, time, salience, age, transference, interference. The subacute window (roughly 1–3 months post-stroke) shows the steepest spontaneous recovery slope (Cramer SC. *Ann Neurol*. 2008;63:272–287).

3. Reasoning walkthrough. The patient is in the high-yield window. Two implications follow. First, prioritize task-specific training: Kleim's specificity principle and Lang et al. (*Arch Phys Med Rehabil*. 2009;90:1692–1698), which observed a mean of 357 gait steps per session (95% CI 296–418) across 312 PT/OT sessions at seven US sites — well below thresholds associated with locomotor recovery in chronic stroke. Second, push toward higher dose. For locomotor goals, even though the Locomotor CPG addresses chronic stroke (>6 months), the underlying mechanism — task-specific stepping at sufficient cardiovascular intensity — applies in subacute care with appropriate medical monitoring. Track steps per session.

4. Outcome measure. Berg Balance Scale at admission, midpoint, and discharge. Berg 0–56. Acute stroke MDC ≈ 7 points (Stevenson TJ. *Aust J Physiother*. 2001;47:29–38). Pair with 10MWT once safe ambulation is established.