Background: Recurrent lower limb pain (RLLP) is common in children, with growth pain (GP) lacking objective diagnostic criteria and often confused with organic pain. This study aims to compare clinical characteristics and post-exercise pain responses among children with GP, disease controls (DC), and healthy controls (HC). Methods: This prospective controlled study (January 2023–March 2025) enrolled 201 children aged 3– 12 years (67 in the GP group, 62 in the DC group, and 72 in the HC group). Baseline data and standardized symptom assessments were collected, followed by a unified standardized jump rope exercise load test. Immediate and 24-hour post-exercise visual analog scale (VAS) pain dynamics were compared. Results: The proportion of GP group participants with bone age advancement ≥ 3 months (44.78%) was significantly higher than in the DC group (16.13%) and HC group (25.00%, P < 0.001). Symptomatically, the GP group predominantly experienced evening/nighttime soreness (89.55%) and short-duration pain (median 31 minutes), whereas the DC group more commonly reported morning stabbing pain (40.32%) and long-duration pain (median 79 minutes) (P < 0.001). Exercise stress testing revealed that pain intensified post-exercise in both GP and DC groups. However, the DC group exhibited a “sharp increase-rapid decline” pattern, whereas the GP group showed a slower recovery. Conclusion: Standardized exercise stress testing reveals distinct pain recovery patterns, serving as a valuable supplement to symptom screening. Nevertheless, its efficacy in directly differentiating GP from organic diseases remains limited. Future research should integrate additional indicators to optimize diagnostic strategies. Keywords: recurrent lower limb pain, growing pains, clinical screening, exercise load assessment, influencing factors
Guo et al. (Sun,) studied this question.