The Most Effective Collaborative Model for ACL Rehab

I have spent the last 5 years of my close to 30-year career in sport science, university teaching, and working as both a strength & conditioning specialist and Kinesiologist in ACL rehab. I have been able to successfully rehab athletes I work with and one of the reasons is the team I use. In my opinion, the strongest model is often an interdisciplinary one, where everyone knows there role and are a specialist in that role. Long gone are the days where the physio does it all. It’s too big a job to do well.

• Sports medicine physician: diagnosis, surgery, medical oversight

• Physiotherapist: pain management, early stage rehabilitation, joint function, tissue healing, BFR, manual therapy, addressing AMI up to approx 12 weeks post op given no major complications or surgeon recommended guidelines. Physios also do their own functional testing to clear athletes for the next stages of rehab.

• Strength & conditioning coach or kinesiologist: strength development, plyometrics, sprinting, change of direction, workload management, performance testing, and return-to-performance

Each profession contributes complementary expertise. Rather than viewing ACL rehabilitation as a process that ends with symptom resolution, a high-performance model views it as a progression from healing → restoring function → building capacity → preparing for the specific demands of sport, with the final stages relying heavily on exercise prescription, coaching, and physical preparation expertise.

Where problems arise, in my experience is when a practitioner views their role as all encompassing versus their role as evolving/changing through the rehab and reconditioning process.

1. Rehabilitation may stop at "normal" rather than "elite"

Physiotherapy education is largely based around restoring function for activities of daily living.

Returning an athlete to:

• cutting at 6 m/s

• sprinting at 10 m/s

• landing from a 30-inch jump

• absorbing 6-8× bodyweight forces

• tolerating hundreds of maximal accelerations per week

requires a different skill set.

The goal should not simply be:

"The knee feels good."

It should be:

"The athlete possesses the physical qualities required to outperform the demands of competition."

2. Strength development may be inadequate

ACL injuries produce profound deficits in:

• maximal strength

• rate of force development

• tendon stiffness

• eccentric braking capacity

• intermuscular coordination

Research consistently shows that maximal strength is one of the strongest predictors of sprinting, jumping, change of direction, and injury resilience.

Without expertise in progressive overload and long-term strength programming, athletes often plateau.

Common examples include:

• goblet squats instead of heavy bilateral squats

• bands instead of high mechanical tension

• high repetitions instead of high force production

• instability exercises replacing heavy loading

3. Insufficient exposure to high forces

Sport exposes athletes to enormous loads.

For example:

• sprinting generates very high hamstring forces

• cutting generates substantial multiplanar knee moments

• landing creates several times bodyweight in ground reaction force

If rehabilitation never exposes tissues to progressively increasing forces, the first exposure may occur during competition.

This violates one of the fundamental principles of exercise science: Adaptations are specific to the magnitude and direction of the imposed demand.

4. Plyometric progression and exposure may be limited

High-quality plyometric programming involves manipulating:

• contact times

• stiffness

• reactive strength

• landing strategies

• horizontal vs vertical force vectors

• unilateral loading

• approach velocities

• surface compliance

• fatigue state

Many rehabilitation programs include jumping but not true plyometric progression.

Instead of developing elastic qualities, athletes simply perform "jump exercises." Athletes need to get into their sport enviroment where there is space to do these complex drills under supervision.

5. Sprint development is often underemphasized

Many return-to-running programs emphasize gradual running progression.

However, running fast exposes tissues to forces much lower than maximal sprinting.

A strength and conditioning approach may instead prioritize:

• restoring maximal strength

• restoring eccentric braking ability

• extensive plyometrics

• sprint drills

• wicket runs

• acceleration mechanics

• progressive maximal velocity exposures

The philosophy is that tissues adapt to force exposure—not merely slower versions of the same movement.

6. Coaching expertise matters

Elite movement quality is not produced by exercises alone. It requires coaching.

Experienced strength and conditioning coaches spend thousands of hours coaching:

• landing mechanics

• acceleration

• deceleration

• trunk positioning

• force application

• rhythm

• stiffness

• coordination

The exercise selection may be identical, but the coaching quality can be dramatically different.

7. Demand analysis may be incomplete

Exercise selection should flow from a detailed understanding of the athlete's sport.

Questions include:

• What velocities are reached?

• How many accelerations occur?

• What are the braking demands?

• What external loads are encountered?

• What energy systems dominate?

• What movement variability exists?

Without a comprehensive demand analysis, rehabilitation risks becoming generic rather than sport-specific.

8. Testing may not reflect performance capacity or be out of date and invalid

Many rehabilitation programs emphasize:

• limb symmetry index (LSI)

• hop tests (known to be invalid)

Performance-based assessment may include:

• relative strength

• eccentric force production

• countermovement jump strategy

• squat jump performance

• reactive strength index

• sprint times

• change-of-direction deficit

• repeated sprint ability

• force-velocity profiling

• deceleration mechanics

An athlete can achieve 90% LSI yet still possess significant deficits in absolute performance.

9. Long-term athletic development may be overlooked

The rehabilitation period presents a unique opportunity to improve the athlete beyond their pre-injury state.

A comprehensive physical preparation program can enhance:

• strength

• power

• sprint ability

• robustness

• work capacity

• body composition

• movement efficiency

If rehabilitation focuses solely on restoring the injured limb, this opportunity may be lost. The S&C’s approach would be far more holistic building other fitness qualities while addressing the knee.

10. The athlete may be "cleared" rather than "prepared"

This may be the most important distinction.

Medical clearance indicates that healing has occurred and major pathology has resolved.

Performance readiness means the athlete has regained the physical qualities required for their sport.

Hop tests, LSI tests, T-tests are all 10-15 years out of date.

An athlete may be cleared based on these results yet remain underprepared for the demands of elite competition.

There is a reason why we have a 30% re-injury rate - not all rehab is equal and not all rehab involves a high calibre S&C or Kinesiologist.