Physical therapy is commonly sought by people with lumbar disc herniation and associated radiculopathy. It is unclear whether physical therapy is effective for this population.To determine the effectiveness of physical therapist-delivered individualized functional restoration as an adjunct to guideline-based advice in people with lumbar disc herniation and associated radiculopathy.This is a preplanned subgroup analysis of a multicenter parallel group randomized controlled trial.The study included 54 participants with clinical features of radiculopathy (6-week to 6-month duration) and imaging showing a lumbar disc herniation.Primary outcomes were activity limitation (Oswestry Disability Index) and separate 0-10 numerical pain rating scales for leg pain and back pain. Measures were taken at baseline and at 5, 10, 26, and 52 weeks.The participants were randomly allocated to receive either individualized functional restoration incorporating advice (10 sessions) or guideline-based advice alone (2 sessions) over a 10-week period. Treatment was administered by 11 physical therapists at private clinics in Melbourne, Australia.Between-group differences for activity limitation favored the addition of individualized functional restoration to advice alone at 10 weeks (7.7, 95% confidence interval [CI] 0.3-15.1) and 52 weeks (8.2, 95% CI 0.7-15.6), as well as back pain at 10 weeks (1.4, 95% CI 0.2-2.7). There were no significant differences between groups for leg pain at any follow-up. Several secondary outcomes also favored individualized functional restoration over advice.In participants with lumbar disc herniation and associated radiculopathy, an individualized functional restoration program incorporating advice led to greater reduction in activity limitation at 10- and 52-week follow-ups compared with guideline-based advice alone. Although back pain was significantly reduced at 10 weeks with individualized functional restoration, this effect was not maintained at later timepoints, and there were no significant effects on leg pain, relative to guideline-based advice.