ACL Rehabilitation · Phase IV Transitional

Targeted Workout Program

Right knee · Isokinetic assessment 23 Jun 2025 · Home equipment
Frequency 3 days / week
Duration 4 weeks
Setting Home · Bands
Goal Return to tennis
Patient age 31 · Female
Clinical rationale: Isokinetic testing shows right quad deficit of 16.7% and right hamstring deficit of 14.9% at 60 deg/s, with a hamstring-to-quad (H:Q) ratio of ~51% — well below the 66% threshold required for safe return to sport. Flexion total work deficit reaches 24.5% (significant impairment band). This program targets three concurrent priorities: (1) close the quad strength gap to ≥90% symmetry, (2) disproportionately load the hamstrings to push H:Q toward 66%, and (3) begin progressive neuromuscular loading to prepare the knee for sport-specific demands.
Quad deficit (60°/s)
16.7%
Target: <10%
H:Q ratio
51%
Target: ≥66%
Flex. total work
24.5%
Target: <10%
Day A Quad & Glute strength
01
Wall sit isometric hold
3 × 30 sec · 60° knee flexion
Quad
Why: Isometric quad loading at mid-range (60°) is the safest entry point — matches the isokinetic test deficit angle. Builds quad activation without shear force on the graft.

How: Back flat against wall, feet shoulder-width, slide down until thighs are at ~60° from floor. Hold. Do not let knees cave inward. Progress to 45 sec in week 2.
02
Step-up with march
3 × 10 reps each leg · 15–20 cm step
Quad
Why: Eccentric quad control during the step-down phase directly targets the deficit pattern. The march at the top adds glute med activation and single-leg stability.

How: Step up leading with the right (involved) leg. At the top, lift the opposite knee to 90°, hold 1 sec, lower slowly (3-count). Keep the standing knee tracking over the 2nd toe throughout.
03
Band-resisted lateral walk
3 × 15 steps each direction
Glute
Why: Glute med index is a Phase IV criteria metric. Lateral resistance directly recruits glute med/min, reducing dynamic valgus during single-leg tasks.

How: Band around ankles or just above knees. Slight squat position (hips back, knees soft). Step laterally keeping toes forward — don't let the feet come together completely between steps.
04
Single-leg Romanian deadlift (bodyweight)
3 × 8 reps each leg · slow 3-sec lower
Hams
Why: Hip-dominant hamstring loading in an open-chain pattern is key to rebuilding the H:Q ratio. Single-leg version also trains proprioception and glute max.

How: Stand on involved leg, hinge at hips sending free leg behind you, keep spine neutral. Reach both hands toward the floor. Lower for 3 counts, drive hips forward to return. Touch a wall lightly for balance if needed.
05
Dead bug
3 × 8 reps each side
Core
Why: Lumbopelvic stability is required for safe single-leg loading. Dead bug trains anti-extension control without any knee stress.

How: Lie on back, arms to ceiling, knees at 90° (tabletop). Press lower back firmly into floor. Slowly lower opposite arm and leg toward floor — exhale throughout. Return without letting the lower back lift. Keep the movement deliberate and slow.
Day B Hamstring priority + balance
01
Band hamstring curl (prone)
4 × 12 reps · band anchored at ankle height
Hams
Why: Directly addresses the 14.9% flexion deficit and the critically low H:Q ratio. 4 sets (vs 3 for quad exercises) reflects the priority of hamstring loading in this phase.

How: Lie prone, band looped around right ankle, anchored to door at floor level. Curl heel toward glute — hold 1 sec at peak, lower 3 counts. Do not rock the pelvis. Use a resistance level that makes the last 2 reps challenging but controlled.
02
Single-leg glute bridge
3 × 12 reps each leg · 2 sec hold at top
Hams
Why: Bridge in single-leg version targets hamstrings and glute max together — both are needed to achieve the Phase V H:Q and glute index thresholds.

How: Lie on back, one foot flat on floor, other leg extended. Drive through the planted heel, lift hips until body forms a straight line shoulder-to-knee. Squeeze glute at top for 2 sec. Do not let the hip of the lifted leg drop.
03
Single-leg balance — eyes open to closed
3 × 30 sec each leg
Neuro
Why: Joint position sense retraining is a Phase III–IV criterion. The test showed deceleration time asymmetry (90 ms R vs 50 ms L at 60°/s) suggesting proprioceptive delay on the involved side.

How: Stand on involved leg, knee slightly bent (not locked). Week 1: eyes open, flat surface, 30 sec. Week 2: progress to eyes closed for the last 15 sec. If wobbling is excessive, use a fingertip touch on a wall.
04
Lateral step-down (step-down eccentric)
3 × 10 reps involved leg · 4-sec lower
Quad
Why: Slow eccentric step-down is one of the most effective exercises for closing quad strength deficits — the eccentric demand closely mirrors what isokinetic testing measures.

How: Stand on involved leg on a 15–20 cm step. Slowly lower the opposite foot toward the floor over 4 counts — do not let it touch. Drive back up. Watch for knee valgus or trunk lean. Use a railing lightly if needed for the first few sessions.
05
Pallof press (band, half-kneeling)
3 × 10 reps each side · 2 sec hold
Core
Why: Anti-rotation core strength is essential for return to sport involving cutting, changes of direction, and racket/pole deceleration forces.

How: Half-kneel perpendicular to band anchor (band at chest height). Hold both hands at sternum. Press straight out, hold 2 sec, return. Resist the band pulling you sideways — don't rotate. Involved knee down for the set challenging the contralateral hip.
Day C Tennis neuro + landing
01
Split-step landing drill
3 × 10 reps · bilateral, low height
Neuro
Why: The split-step is tennis's most fundamental movement — a small bilateral hop timed to the opponent's contact. It requires exactly the reactive eccentric landing mechanics Phase IV is preparing. Starting bilaterally at low amplitude is safe and directly sport-relevant.

How: Stand in ready position (slight squat, weight on balls of feet). Step off a 10 cm platform and land on both feet simultaneously — soft "quiet landing": knees bent, hips back, weight even. Absorb for 2 sec. Focus: no knee cave, symmetrical weight. This is a landing drill, not a jump — no take-off yet.
02
Bilateral calf raise → single-leg hold
3 × 15 bilateral + 10 sec SL hold each
Neuro
Why: Tennis involves frequent forefoot loading, rapid push-off during lateral movement, and deceleration after groundstrokes. Calf strength and single-leg ankle proprioception underpin all of these.

How: Stand on a step edge (or flat floor). Rise on both feet, then shift weight to the right (involved) foot for a 10-sec hold at the top. Lower slowly. Maintain a soft knee — do not lock out. In week 2, add a slight trunk rotation during the hold to simulate a follow-through position.
03
Rotational balance — ball toss against wall
3 × 8 throws each leg · single-leg stance
Neuro
Why: In tennis, the knee is loaded during trunk rotation on every groundstroke — the contact leg absorbs rotational force while the upper body swings. This drill trains exactly that pattern: single-leg balance + ipsilateral trunk rotation under perturbation.

How: Stand on the involved leg, 1 m from a wall. Toss a small ball against the wall with a forehand-like motion and catch it. The catching and throwing creates trunk rotation that perturbs the stance knee. Keep the standing knee slightly bent throughout. Progress in week 2: close eyes for 2 sec after each catch before the next throw.
04
Lateral band walk — wide stance, diagonal
3 × 10 reps diagonal forward + backward
Glute
Why: Tennis court movement is predominantly diagonal — open-stance groundstrokes, split-step to lateral sprint, recovery steps. Diagonal band walks begin bridging from pure lateral glute loading toward the multiplanar patterns of court movement.

How: Band above knees, squat position. Step diagonally forward-right, then forward-left (10 steps), then reverse backward. Maintain consistent squat depth — do not stand up between steps. Imagine moving to retrieve a wide ball on each diagonal step.
05
Nordic hamstring curl (assisted, partial range)
3 × 6 reps · feet anchored under sofa
Hams
Why: Nordic curl is the gold-standard eccentric hamstring exercise for ACL rehab and re-injury prevention. The hamstring is the primary dynamic restraint against anterior tibial translation — critical in tennis where the knee absorbs high-speed deceleration forces during lateral sprints and split-steps.

How: Kneel on a mat, hook feet under a heavy sofa or have someone hold your ankles. Arms crossed on chest (or hands ready to catch). Slowly lower your torso forward — control the descent as far as possible. Use hands to catch at the bottom. Drive back up using hips. Week 1: stop at ~45° forward lean. Week 2: aim for 50°.
Day A Quad strength — progressed
01
Wall sit — add band resistance
3 × 45 sec · band above knees, push out
Quad
Progression from week 1: Increased duration (30→45 sec) + added band above knees to simultaneously challenge glute med, addressing the H:Q and glute index criteria simultaneously.

How: Same wall sit position at 60°. Loop band above knees, press outward against it throughout the hold. The outward push should not break form.
02
Weighted step-up (add band)
4 × 10 reps involved leg · band above knee
Quad
Progression: 3→4 sets; band above knee adds valgus challenge. Increase step height to 20–25 cm if week 1 was pain-free.

How: Same movement as week 1. With band above knee, actively press it outward as you step up and lower. The march at the top is now held for 2 sec instead of 1.
03
Split squat (static lunge)
3 × 10 reps each leg · bodyweight
Quad
Why: Replaces the bilateral mini squat to increase single-leg demand. Static split squat allows controlled quad loading with less balance challenge than a walking lunge.

How: Take a large step forward (involved leg in front). Lower back knee toward floor — keep front shin as vertical as possible. Drive through front heel to return. Lower for 3 sec, rise for 2 sec. Keep torso upright.
04
Single-leg Romanian deadlift — band loaded
3 × 10 reps each leg · band under foot
Hams
Progression: Band under the standing foot, held in both hands, adds resistance to the hip extension phase — increases hamstring demand directly.

How: Step on middle of band with standing foot, hold both ends at hip height. Hinge as before — now the band pulls you toward the floor, increasing eccentric demand on the hamstring. Keep the lowering phase at 3 counts.
05
Single-leg squat to chair (assisted)
3 × 8 reps involved leg · lightly touch chair
Quad
Why: Phase IV exit criterion explicitly requires "10 repetitions single-leg squat with proper form through at least 60° knee flexion." This progression targets that goal.

How: Stand in front of a chair (seat ~45 cm high). Balance on involved leg, arms forward. Slowly lower to just touch the seat — do not sit down — then drive back up. Lower for 4 sec. Focus on: knee over 2nd toe, no trunk lean toward the standing side.
Day B Hamstring priority — progressed
01
Band hamstring curl — heavier band + pause
4 × 12 reps · 2 sec isometric hold at 90°
Hams
Progression: Heavier band + isometric pause at 90° knee flexion corresponds directly to the angle where the isokinetic test showed the H:Q deficit is most pronounced.

How: Same prone setup. Curl to 90°, hold 2 sec, continue to peak, return slowly. The 2-sec pause is the key addition — do not skip it.
02
Nordic curl — greater range
3 × 8 reps · aim for 60° forward lean
Hams
Progression: Extend range from ~45° to ~60° forward lean. Still use hands to catch at the bottom — the goal is to control as much range as possible, not to reach the floor.

How: Same setup. Aim to control the descent to ~60° before catching. Count: lower for 4 sec, catch, use hip thrust + hands to return. Rest 45 sec between reps.
03
Single-leg balance — perturbation
3 × 5 throws each leg · partner or wall toss
Neuro
Progression: Adding perturbation (unexpected force) to single-leg balance directly trains the reactive neuromuscular response required for sport.

How: Stand on involved leg. Toss a ball against a wall at chest height and catch it — the catching action creates trunk rotation and perturbation. Or: partner lightly pushes shoulder from random angles while you maintain balance. Keep the standing knee slightly flexed throughout.
04
Lateral step-down — progressed height
3 × 12 reps · increase to 20–25 cm step
Quad
Progression: Height increase from 15→20-25 cm increases the eccentric quad demand. If pain-free at 12 reps with good form, this is the clearest sign of closing the deficit.

How: Same movement. With the increased height, watch especially for: hip drop on the lowering side (glute med fatigue) and forward trunk lean (anterior load shift). Both indicate need to reduce height.
05
Hip hike with band
3 × 15 reps each side
Glute
Why: Hip hike isolates quadratus lumborum and glute med in a way that directly simulates single-leg stance demands during running gait.

How: Stand on involved leg on a step edge. Let the free hip drop below step level, then actively hike it up above level using the standing-leg hip. Band can be looped around thighs for added resistance. The movement is a lateral pelvic tilt — not a trunk lean.
Day C Tennis power + jump prep
01
Split-step → lateral sprint step (2 steps)
3 × 8 reps each direction
Neuro
Progression from week 1: Adds the lateral first-step reaction after the split-step landing — replicating the most common movement pattern in tennis: split → push-off toward the ball.

How: From standing, perform the split-step bilateral landing (soft, controlled). Immediately upon landing, take 2 explosive lateral steps to the right (or left). Stop with a controlled split-step position. The lateral push-off is the new load — keep it moderate intensity, not a full sprint. Focus on the quality of the landing, not the speed of the steps.
02
Squat jump — bilateral, low amplitude
3 × 6 reps · 5–8 cm height only
Neuro
Why: The power deficit data (extension 16.7%, flexion 22.3%) shows the knee needs to begin producing rapid bilateral force before advancing to single-leg or sport-specific plyometrics. Low-amplitude squat jumps are the safest entry point.

How: Feet shoulder-width, small squat (30–40°), jump just 5–8 cm off the floor. Land softly — quiet landing cues: knees bent, hips back, symmetrical weight. Focus on landing mechanics, not height. Stop if pain or swelling occurs.
03
Rotational balance — forehand + backhand patterns
3 × 10 throws each leg · mimic stroke follow-through
Neuro
Progression from week 1: Now alternates forehand and backhand toss patterns, and adds a follow-through trunk rotation to the catch — replicating the full rotational load of a groundstroke on a planted front leg.

How: Stand on involved leg. Alternate throwing the ball with a forehand swing (right-to-left rotation) and a backhand swing (left-to-right). After catching, hold the follow-through position for 2 sec before resetting. The planted knee should remain slightly bent and stable throughout the full swing arc.
04
Reverse Nordic (partial, kneeling)
3 × 8 reps · lean back 20–30° only
Quad
Why: Reverse Nordic targets the rectus femoris eccentrically at length — a weakness commonly identified in ACL rehab. In tennis, the rectus femoris is highly active during the serve action and overhead shots.

How: Kneel on a mat (pad knees well). Arms at sides or crossed on chest. Keeping hips extended and body straight from knee to shoulder, slowly lean back 20–30°, hold 2 sec, return. Do not go further than this in weeks 3–4. The sensation is a significant quad stretch under tension — expect this to be challenging.
05
Single-leg squat — freestanding (no chair)
3 × 6 reps involved leg · to 60° only
Quad
Why: Direct practice of the Phase IV exit criterion, and highly relevant to tennis — the open-stance forehand requires single-leg loading to exactly this depth on the dominant side.

How: Arms forward for counterbalance. Lower to 60° flexion (thigh at ~45° from floor). If form breaks — knee caves, trunk collapses — reduce to 40° ROM and build from there. By week 4, the target is 10 clean reps at 60°.
4-week progression overview
Week 1
Load tolerance
Establish exercise patterns. 3 sets most exercises. Bilateral landing mechanics. Quad isometrics + hip hinging.
Week 2
Volume increase
Add reps / hold duration. Begin eyes-closed balance. Nordic curl range to 45°. Add perturbation.
Week 3
Load + complexity
Introduce split squats, SL squat to chair. Add band resistance to SL RDL. First bilateral jump drills.
Week 4
Phase V readiness
Progress toward 10× SL squat at 60°. Nordic range to 60°. Begin low squat jumps. Re-test criteria.
Phase V progression criteria — current status
Quad index ≥90% @ 60 deg/s — currently 83.3%. Requires ~11% further improvement in peak torque symmetry.
83.3% / 90%
Hamstring index ≥90% @ 60 deg/s — currently 85.1%. Close, but below Phase V threshold.
85.1% / 90%
H:Q ratio ≥66% — currently ~51%. This is the most significant gap and the main driver of hamstring focus in this program.
51% / 66%
?
10× single-leg squat to 60° with proper form — not yet assessed. Day A progression in weeks 3–4 directly targets this criterion.
Assess wk 4
?
Drop vertical jump with good control — not yet assessed. Day C progression in weeks 1–4 builds toward this.
Assess wk 4
?
KOOS-sports questionnaire >70% — not reported. Should be completed at next clinical appointment.
Not reported