Resistance training with linear periodization is superior to the '3x10 reps protocol' after anterior cruciate ligament reconstruction: a randomized controlled trial

Abstract

Objective: To investigate the effects of linear periodization (LP) resistance training after anterior cruciate ligament reconstruction (ACLR).

Setting: Physiotherapy clinic.

Participants: Male recreational athletes who underwent ACLR.

Main outcome measures: Knee extensor and flexor isometric strength, hop tests performance, patient-reported function (International Knee Documentation Committee, IKDC), and psychological readiness (Anterior Cruciate Ligament - Return to Sport after Injury, ACL-RSI).

Results: Twenty-two participants (mean age 27 ± 6 years) were randomized to either a LP program or the traditional '3x10 reps protocol'. The LP group demonstrated greater knee extensor strength gains compared to the 3x10 group (p = 0.03): 51 % (95 %CI, 28 to 73) vs. 26 % (95 %CI, 11 to 40). No statistically significant difference (p = 0.11) in knee flexor strength gains was observed between the LP group (45 %; 95 % CI, 18 to 71) and the 3x10 group (23 %; 95 % CI, 7 to 39). Six months after ACLR, the LP group exhibited a greater knee extensor limb symmetry index (97 ± 10 % vs. 85 ± 11 %, p < 0.01) and higher ACL-RSI scores (68 ± 18 vs. 53 ± 14, p = 0.04). No significant between-group differences were found in hop performance or IKDC scores (p > 0.05).

Conclusion: A resistance training program incorporating block-structured LP is more effective than the traditional '3x10 reps protocol' in enhancing knee extensor strength and psychological readiness during ACLR rehabilitation.

Keywords: ACL; Physiotherapy; Rehabilitation; Strength training.