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3 The effect of progressive resistance exercise on knee muscle strength and function in participants with persistent hamstring deficiency following ACLR
  1. Bo Bregenhof
  1. Sports medicine clinic, Vejle Hospital, SLB, Beriderbakken 4, Danmark


Introduction We investigated the effect of progressive resistance exercise on knee-muscle strength and joint function in anterior cruciate ligament reconstructed (ACLR) participants with persistent hamstring muscle deficiency, 12–24 months post-surgery.

Materials and Methods A prospective, superiority, randomised controlled trial (RCT) with parallel groups, balanced randomization (1:1) and blinded outcome assessment (level of evidence: II). ACLR (hamstring autograft) participants with persistent hamstring muscle deficiency were recruited, 12–24 months post-surgery, and randomised to either 12-weeks of supervised progressive strength and neuromuscular training (SNG), or home-based low-intensity exercises (CON). Primary outcome was between-group change in maximal isometric knee flexor muscle strength at 12-weeks follow-up. Secondary outcomes included measures of objective strength, MRI and patient reported outcomes.

Results Fifty-one participants (45% women, 27 ± 6 years) were randomized to SNG (n = 25) or CON (n = 26), with data obtained from 88% of participants at 12-weeks follow-up. SNG improved more than CON from baseline to 12 weeks in knee flexor muscle strength (0.18 Nm/kg, 95% CI 0.07 to 0.29; p = 0.002). Furthermore, the SNG group improved in KOOS Pain (4.56, 95% CI 0.43 to 8.69; p = 0.031) and KOOS activity of Daily Living Function (4.71, 95% CI 1.20 to 8.22; p = 0.010) than CON.

Conclusion In ACLR participants with persistent hamstrings muscle deficiency, 12 weeks of supervised progressive strength training was superior compared to low-intensity home based exercises (usual care) for improving knee flexor muscle strength and some patient reported outcomes.

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