How long should I do prehab before ACL surgery?

Ideally 4-6 weeks of prehab before ACL surgery. Research shows patients who complete prehab have better outcomes, faster recovery, and improved post-surgery function. Even 2 weeks of focused prehab can make a meaningful difference.

What exercises should I do before ACL surgery?

Focus on quad activation (straight leg raises, quad sets), hamstring curls, hip strengthening (clamshells, bridges), range of motion exercises, and low-impact cardio like cycling or swimming. The goal is to enter surgery as strong as possible.

Does ACL prehab actually improve outcomes?

Yes. Studies show prehab before ACL surgery leads to faster return of quad strength, better knee function scores at 3 and 6 months, reduced post-operative swelling, and earlier return to daily activities and sport.

Should I walk on my torn ACL before surgery?

Most patients can walk on a torn ACL once swelling subsides. Walking helps maintain muscle function and range of motion. Avoid pivoting, cutting, or any activity that causes the knee to give way. Follow your surgeon's specific guidance.

ACL Prehab Guide: Pre-Surgery Exercises & Preparation Tips

Why Prehab Matters

Prehabilitation ("prehab") is the process of preparing your body and mind for ACL reconstruction surgery. Research consistently shows that patients who complete prehab programs have:

                            Benefits of Prehab
                            Faster recovery: Patients regain strength and function more quickly
Better outcomes: Improved knee function scores at 6 and 12 months
Less muscle loss: Starting stronger means less atrophy to overcome
Reduced complications: Lower risk of extension deficit (arthrofibrosis)
Mental preparation: Know what to expect and feel more confident
Practical readiness: Home set up, work arranged, support in place

                        

The "Quiet Knee" Goal

Many surgeons prefer to operate on a "quiet knee"—one that has minimal swelling, full range of motion (especially extension), and good quad function. If your knee is still very swollen or stiff, surgery may be delayed to improve outcomes.

Prehab goals before surgery:

Full knee extension (0° or matching your other leg)
Minimal swelling
Good quad activation (can do straight leg raise without lag)
Flexion of at least 120°

Physical Preparation

Priority 1: Restore Full Extension

Full knee extension before surgery is critical. Patients who go into surgery with an extension deficit have higher rates of permanent stiffness (arthrofibrosis).

Prone Hangs 10-15 min, 3-4x daily Quad Sets Focus on full knee lock

Priority 2: Quad Activation & Strength

Strong quads before surgery = faster quad recovery after. The quad muscle often "shuts down" after ACL injury, so re-activating it is key.

Quad Sets 100+ per day in sets of 10-20 Straight Leg Raises All 4 directions, 3 sets of 15 Mini Squats If knee allows, pain-free range

Priority 3: Hip & Core Strength

Strong hips and core support your knee and make early recovery exercises easier.

Bridges 3 sets of 15-20 Clamshells 3 sets of 20 each side Side-lying Hip Abduction 3 sets of 15 each side

Priority 4: Cardio Fitness

Maintain cardiovascular fitness without stressing your knee:

Stationary bike: If ROM allows (typically best option)
Swimming/pool: Non-weight bearing cardio
Upper body ergometer: Arm cycling
Rowing: If knee tolerates the motion

Sample Weekly Prehab Schedule

Exercise	Sets x Reps	Frequency
Prone Hangs	10-15 min	3-4x daily
Quad Sets	10 sets of 10	Throughout day
Straight Leg Raises (4 way)	3 x 15 each	2x daily
Bridges	3 x 15-20	Daily
Clamshells	3 x 20 each	Daily
Mini Squats	3 x 10-15	Daily (if tolerated)
Cardio (bike/pool)	20-30 min	3-5x per week

Managing Swelling

Reducing swelling before surgery helps achieve the "quiet knee" and sets you up for better outcomes.

RICE Protocol

Rest, Ice, Compression, Elevation. Ice for 15-20 minutes several times daily. Keep leg elevated above heart when resting.

Compression

Wear a compression sleeve or wrap during the day. Helps control swelling and provides some stability.

Movement

Gentle movement actually helps reduce swelling by promoting circulation. Don't stay completely sedentary.

Avoid Aggravation

Stay off activities that cause giving way, pain, or increased swelling. Protect your knee from further injury.

Mental Preparation

ACL recovery is as much mental as physical. Preparing psychologically helps you cope with the challenges ahead.

Set Realistic Expectations

Recovery takes 9-12+ months for return to sport
Progress isn't linear—there will be ups and downs
The first 2 weeks are often the hardest physically
Months 3-6 can be mentally challenging (feeling better but not cleared)
Most people do very well—but it takes time and patience

Emotional Preparation

Grief is normal: You may grieve the loss of your pre-injury self
Frustration happens: Recovery can feel slow and tedious
Anxiety is common: Fear of re-injury affects most people
Identity shifts: Athletes often struggle when sport is taken away

Build Your Support System

Tell friends and family how they can help
Connect with others who've been through ACL surgery
Consider seeing a sports psychologist if anxious
Join online communities (Reddit r/ACL, Facebook groups)

Mental Health Resources

Depression and anxiety rates are elevated after ACL injury. If you're struggling, please reach out.

Mental Health Support Depression Screening

Practical Preparation

Home Setup

Recovery space: Set up a comfortable area on the main floor if possible (avoid stairs initially)
Bed access: Low bed or one you can get in/out of with crutches
Bathroom: Ensure you can safely access toilet and shower
Shower seat: Very helpful for the first 1-2 weeks
Ice machine: Game Ready, Polar Care, or similar (often rentable)
Clear pathways: Remove tripping hazards, rugs, cords

Supplies to Have Ready

Crutches (practice using them before surgery)
Ice packs or ice machine
Compression wraps or sleeves
Pillows for elevation
Comfortable loose shorts/pants
Slip-on shoes
Shower chair/bench
Reacher/grabber tool (helpful but not essential)
Entertainment: books, streaming, podcasts

Work & Life Arrangements

Time off: Plan for at least 1-2 weeks off work (more for physical jobs)
Driving: You won't drive for 4-6+ weeks (left leg surgery may be sooner if automatic)
Help at home: Arrange for someone to assist the first few days
Meals: Prep freezer meals or arrange meal delivery
Pets: Arrange help with dog walking, etc.
PT appointments: Know where you'll go and schedule first appointments

Pre-Surgery Checklist

Questions to Ask Your Surgeon

Before surgery, make sure you understand the plan:

About the Surgery

Which graft type will you use and why?
How long have you been doing ACL surgeries?
What's your approach to fixation?
Will you address any meniscus damage?
What are the risks and potential complications?

About Recovery

What's your rehabilitation protocol?
When can I bear weight?
How long will I need crutches/brace?
When can I drive?
When can I return to work?
What's your timeline for return to sport?
What criteria do you use for return-to-sport clearance?

About Follow-Up

When is my first post-op appointment?
How do I contact you if I have concerns?
What warning signs should I watch for?
Do you coordinate with my physical therapist?

The Day Before Surgery

Follow fasting instructions: Typically no food/drink after midnight
Shower: Many surgeons request a special antiseptic wash
Prepare your bag: Loose clothes, insurance card, ID, list of medications
Set up your recovery space: Bed, ice, pillows, entertainment
Get a good night's sleep: Easier said than done, but try to rest
Review arrival time: Know when and where to show up
Confirm your ride: You cannot drive yourself home

Ready for Surgery?

Once you've completed your prehab and you're mentally and practically prepared, you're ready for the next step.

What to Expect: Weeks 0-2 Exercise Library

ACL Prehabilitation Guide