Figure 8. Overview of exercise selection for quadriceps training after anterior cruciate ligament reconstruction (ACLR).

After anterior cruciate ligament reconstruction, quadriceps training should begin with quadriceps setting and be developed onto both open and closed-kinetic-chain load progressions. Strength training load progressions should be primarily advanced through the progression of external load, and exercises that load the quadriceps close to volitional fatigue/task failure at relatively long muscle lengths should be prescribed to enhance muscular hypertrophy. Lastly, a specific load progression to enhance quadriceps rate-of-force development should be prescribed throughout rehabilitation.

1-RM, concentric one-repetition maximum of the surgical limb; AD, assistive device; BFR, blood flow restriction; quad set, quadriceps setting exercise; black arrows, exercise progression pathway; blue boxes, exercise progression for quadriceps rate-of-force development; boxes with red glow, exercise with blood flow restriction; CKC, closed-kinetic-chain; green boxes, open-kinetic-chain exercise selection; grey boxes, closed-kinetic-chain exercise selection; LAQ, long-arc-quad exercise; MAX, maximal; NPRS, numeric pain rating scale; OKC, open-kinetic-chain; RFD, rate-of-force development; SAQ, short-arc-quad exercise; SCC, stretch-shortening cycle; SLR, straight leg raise exercise; SUBMAX, submaximal; TKE, terminal knee extension.