Background/Objectives: LAS is common in adolescents, yet early management strategies differ. The traditional PRICE + NSAIDs protocol focuses on short-term symptom relief, whereas the PEACE and LOVE framework emphasizes education, early optimal loading, and progressive exercise. This study compared functional recovery between these two approaches. Methods: A prospective randomized study enrolled 76 adolescents (12–17 years) with first-time LAS, allocated to PRICE + NSAIDs or PEACE and LOVE using a computer-generated randomization sequence with concealed envelope allocation; 65 completed follow-up (PRICE n = 32; PEACE and LOVE n = 33). Functional performance was assessed at 1–2, 5–7, and 12–15 weeks using Biodex isokinetic dynamometry and the Y-Balance Test composite score (YBT-CS). Outcomes were expressed as side-to-side deficits (uninjured − injured limb) and analyzed using two-way mixed repeated-measures analysis of variance, with Group (PRICE + NSAIDs vs. PEACE and LOVE) as the between-subject factor and Time (1–2, 5–7, and 12–15 weeks) as the within-subject factor. Results: Significant main effects of time were observed for IN strength at 60°/s (F = 5.73, p = 0.006) and 120°/s (F = 10.15, p < 0.001), EV strength at 120°/s (F = 6.82, p = 0.003), ankle ROM at 60°/s (F = 12.79, p < 0.001) and 120°/s (F = 13.09, p < 0.001), and YBT CS (F = 6.91, p = 0.002), indicating progressive recovery across follow-up. No significant group effects or time × group interactions were detected for any outcome (all p > 0.05). Conclusions: Both rehabilitation protocols were associated with progressive functional recovery following adolescent LAS. No statistically significant between-group differences or differential recovery trajectories were detected over 12–15 weeks. These findings suggest that an active, education-focused rehabilitation approach yields functional outcomes comparable to traditional PRICE + NSAIDs management in the short term. Larger studies with longer follow-up are required to determine whether clinically meaningful differences exist between protocols. Trial registration: ClinicalTrials.gov: NCT07287020; registered 3 December 2025 (retrospectively registered).