The Effect of Blood Flow Restriction Training on Quadriceps Activity After Anterior Cruciate Ligament Reconstruction: A Preliminary Randomized Controlled Trial

After anterior cruciate ligament reconstruction, a crucial priority is restoring knee muscle strength, especially the quadriceps, to reach the pre-injury strength levels as fast as possible. A feasible alternative to heavy loading might be blood flow restriction training that may elicit quadriceps muscle strength adaptations using low external loads. This study assessed whether quadriceps strengthening using low load blood flow restriction (LL-BFR) would enhance electromyographic (EMG) activity of the vastus medialis (VMO), vastus lateralis (VLO), and rectus femoris (RF) similar to quadriceps strengthening using heavy loads resistance training (HLRT). The secondary objective was to assess intra-quadriceps regional EMG differences between the 3 quadriceps muscle heads.