Knee Pain Exercises: A Phase-Based Protocol for Patellofemoral, IT Band, and Overuse Knee Pain

What if your knee pain isn’t a knee problem?

For most non-traumatic knee pain — the kind that creeps in after a few weeks of running, the kind that flares walking down stairs, the kind that aches when you stand up from a chair — the strongest treatment effects in the literature don’t come from strengthening the knee at all. They come from strengthening the hip. A 2014 randomized trial by Khayambashi and colleagues compared eight weeks of isolated posterolateral hip strengthening against eight weeks of isolated quadriceps strengthening for patellofemoral pain, and the hip group came out with greater pain reduction and greater function — without training the knee directly.¹

That single finding reframes how this protocol is built.

What follows is a three-phase plan: calm it down (weeks 0–2), strengthen the whole chain (weeks 2–8), and build the prevention layer (ongoing). Sets, reps, frequency, and progression triggers are pulled from the JOSPT clinical practice guideline, the Manchester and Gold Coast PFP consensus statements, and a stack of randomized trials.¹²³⁴ This is for non-traumatic, non-surgical knee pain — the patellofemoral, iliotibial band, and overuse pain that responds to load management and progressive strengthening. If your pain followed a fall, a twist, an audible pop, or comes with locking, giving way, or significant swelling, see a clinician before doing any of this.

Phase 0: Three Pains, Three Protocols — Diagnose Before You Dose

Before you do a single rep, figure out which knee problem you actually have. The three most common non-traumatic knee complaints look similar from the outside but respond to different work.

Diagnosis	Where it hurts	When it hurts	Aggravators	What it is
Patellofemoral pain (PFPS / “runner’s knee”)	Around or behind the kneecap	Going up/down stairs, after prolonged sitting (“theater sign”), squatting	Hills, deep squats, prolonged flexion	Pain at the patellofemoral joint, often associated with hip and trunk control deficits23
Iliotibial band syndrome (ITBS)	Lateral (outside) of the knee	A predictable distance into a run, then sharply worse	Downhill running, increased mileage	Lateral knee pain in distance runners, associated with hip abductor weakness56
Patellar tendinopathy (“jumper’s knee”)	Just below the kneecap on the patellar tendon	Loading the knee — jumping, decelerating, squatting	Volume spikes in jumping/sprinting sports	A load-related tendon condition that responds to progressive tendon loading

The Manchester (2016) and Gold Coast (2018) consensus statements, drafted by the international PFP research community, place exercise therapy — combining hip and knee strengthening — at the top of the evidence pyramid for patellofemoral pain.⁴⁷ The 2019 JOSPT clinical practice guideline came to the same conclusion with grade A recommendations.² For ITBS, the systematic review evidence consistently points back to hip abductor function as the rehab target.⁶⁸

Red flags — stop and see a clinician

These aren’t subtle. If any apply, exit this protocol:

• A traumatic mechanism — twist, fall, contact, audible pop
• The knee gives way, locks, or won’t fully straighten
• Significant swelling within 24 hours
• Pain at rest or pain that wakes you at night
• Fever, redness, or warmth around the joint
• Numbness, weakness, or pain radiating from the back

The PFP guideline specifically frames this as a clinical reasoning step: rule out red flags first, then dose exercise.²

Phase 1: Calm It Down (Weeks 0–2)

The goal of the first two weeks is not to fix the knee — it is to settle it down enough that you can train.

Most people make the same mistake here. They either rest completely (the knee gets weaker, the surrounding muscles atrophy, and the pain returns the moment they try anything) or they push through (and stay stuck in a flare for months). Neither works. The right move is what sports physiotherapists call relative rest — back off the aggravating activity, but keep loading the joint in pain-free ranges every day.

Three movements. Daily. Every one of them is below the irritation threshold.

Quad isometrics / wall sits. Sit against a wall with your knees bent to a depth that produces no pain — for some people that’s 30 degrees, for others 60. Hold for 45 seconds. Repeat 5 times with 30 seconds between holds. Isometric quad work activates the muscles that protect the patellofemoral joint without putting it through aggravating ranges of motion. Erik Meira, the sports physical therapist behind The PT Inquest podcast, has spent years pointing out that tendons and irritated joints both respond well to isometrics in the early phase — they reduce pain acutely and load the tissue without provoking it.

Straight-leg raises. Lie on your back, one leg straight, one knee bent. Lift the straight leg to about 45 degrees, hold for 2 seconds, lower with control. 3 sets of 12. This trains the quadriceps with zero patellofemoral compression — the joint doesn’t move, so it can’t get angry.

Side-lying clamshells. Lie on your side, hips and knees bent at 45 degrees, feet stacked. Open the top knee like a clamshell while keeping your pelvis dead still. 3 sets of 15 per side. This is your first hip abductor input, and the research on gluteal EMG activation supports the clamshell as one of the highest-ratio glute exercises in the rehab literature.

The pain rule: during these movements, pain stays at or below 3/10. After your session, pain returns to your pre-session baseline within 24 hours. If either rule fails, drop the load — shorter holds, fewer reps, smaller range — until both rules hold for two consecutive sessions.²

Aerobic swap. Running, hiking, and high-impact sports are out for these two weeks. Stationary cycling (low resistance, comfortable cadence, knee-pain-free range) and pool work are in. If you usually use cardio for stress management or weight control, our Zone 2 minimum-dose guide shows how to keep an aerobic stimulus going on a bike or rower without irritating the knee.

This phase is also where wearable data earns its keep. A flare-up doesn’t always announce itself with sharp pain — sometimes it shows up first as a higher resting heart rate the next morning, or an overnight HRV that hasn’t recovered to baseline. SensAI flags days where overnight HRV and resting HR signal that yesterday’s session is still being absorbed, which is the cue to repeat the same load rather than progress. The structural pattern here is the same one we used in our lower back pain protocol — calm the tissue first, train the system second.

Progression checkpoint to Phase 2: You can complete a 20-minute walk and the three movements above without provoking pain >3/10 during, and without a pain rebound the next day. That’s the ticket to phase 2.

Phase 2: Strengthen the Whole Chain (Weeks 2–8)

Hip-and-knee strengthening beats knee-only strengthening for patellofemoral pain. This isn’t a small effect or a contested finding — it’s the headline conclusion of the strongest evidence we have.

Nascimento and colleagues’ 2018 systematic review and meta-analysis in JOSPT pooled 14 trials with 673 patients with patellofemoral pain.⁹ The conclusion was unambiguous: combined hip and knee strengthening produced larger reductions in pain and larger gains in activity than knee strengthening alone. Lack and colleagues reached the same conclusion three years earlier — a 2015 systematic review in BJSM found that adding proximal (hip and trunk) work to knee rehab improved both short- and long-term outcomes.¹⁰

Christopher Powers, PhD, PT, FAPTA, who co-directs the Musculoskeletal Biomechanics Research Lab at USC and authored the 2014 RCT cited at the top of this article, has argued for years that the patella is the bottom of a kinetic chain — and that controlling its motion often means controlling the femur underneath it. As Powers and colleagues have framed it across multiple papers, the knee tracks where the hip allows it to track. If the hip drops, the femur internally rotates, the knee caves inward, and the patellofemoral joint absorbs the consequence.¹¹¹

For ITBS, the same hip story holds. Fredericson’s 2000 study at Stanford found that distance runners with iliotibial band syndrome had hip abductor torque that was significantly weaker on the injured side than the uninjured side, and that a six-week hip strengthening program returned 22 of 24 athletes to pain-free running.⁵ Reed Ferber, PhD, who runs the Running Injury Clinic at the University of Calgary, has spent his career building this hip-injury link out across thousands of running injury cases. Beers and colleagues’ multimodal physiotherapy trial in Physiotherapy Canada, which included hip abductor strengthening as a core component, found significant pain and function improvements for ITBS patients within six weeks.⁸

The takeaway is simple: in this phase, you train the hip more than you train the knee.

The 6-week structure: 2x HIP DAY + 1x KNEE DAY per week

You’ll do three sessions per week — two hip days and one knee day — with at least 48 hours between hip sessions. Total time per session: 25–35 minutes.

HIP DAY (2x per week)

These exercises sit at the top of the EMG and clinical-outcome literature for gluteus medius and gluteus maximus recruitment. Build them in this order, with 60–90 seconds rest between sets.

Exercise	Sets x Reps	Tempo	Notes
Glute bridge (double-leg) → single-leg	3 x 10–12	2s up, 1s hold, 2s down	Progress to single-leg in week 4
Side-lying hip abduction	3 x 12–15/side	Controlled	Add ankle weight in week 5
Banded clamshell	3 x 15/side	2s open, 2s close	Move band one notch tighter every 2 weeks
Side plank with hip abduction	3 x 8/side	2s lift, 2s lower	Replaces basic side plank by week 4
Step-ups (hip-dominant pattern, 6–12” box)	3 x 8/side	Drive through heel	Increase box height as control improves
Single-leg Romanian deadlift (bodyweight → light DB)	3 x 8/side	3s down, 1s up	Earn weight by holding good form

For ITBS specifically, prioritize side-lying hip abduction, the clamshell, and the side plank with hip abduction — these isolate the gluteus medius and the posterolateral hip, which is the structure most directly implicated in IT band overload at the knee.⁵⁶⁸ Our hip mobility routine pairs naturally with HIP DAY as a 5-minute warm-up — the routine reactivates the same glute pattern these exercises will then load.

KNEE DAY (1x per week)

Exercise	Sets x Reps	Tempo	Notes
Spanish squat (banded or against wall)	3 x 10–12	3s down, 2s up	Stops at first hint of knee pain
Step-down (4–6” box, slow eccentric)	3 x 8/side	4s down, 1s up	Watch the knee — it should not cave inward
Terminal knee extension (band-resisted)	3 x 12	Controlled	Targets the last 20° of extension
Heel raise → single-leg heel raise	3 x 12	2s up, 2s down	Strong calves protect the knee on landing

The Spanish squat is a hidden gem here. By anchoring a band behind the knees and sitting back into it, you load the quadriceps heavily without the forward knee travel that aggravates patellofemoral pain. It’s a staple in modern PFP and patellar tendinopathy rehab and lets you keep training the quad even when full-depth squatting still flares the joint.

Progression rules. Add load (heavier band, ankle weight, deeper box, more reps) only when you can complete all sets at the top of the rep range with clean technique and zero pain spike during or 24 hours after. The Neal et al. 2024 BJSM best-practice guide for PFP — which synthesized systematic-review evidence with patient input and expert reasoning — emphasizes this kind of monitored, individualized progression over fixed templated dosing.¹²

This is the part of the program that benefits most from an adaptive plan. A static six-week grid assumes you’ll sleep well, eat well, manage stress well, and recover linearly. Real life doesn’t cooperate. SensAI builds the HIP DAY / KNEE DAY rhythm and reschedules sessions when overnight recovery, sleep duration, or HRV indicate the previous session is still being absorbed — so progression is paced by the body’s actual recovery, not by what the calendar says should be possible.

Phase 2 dosing summary

Week	Hip Day Sets	Knee Day Sets	Aerobic	Pain Threshold
2–3	3 sets, low-end reps	3 sets, low-end reps	Bike 20–30 min, 2x/week	≤3/10 during; 24h return
4–5	3 sets, mid reps; add load	3 sets, mid reps	Bike or pool 25–35 min, 2x/week	≤3/10; 24h return
6–7	3 sets, top reps; single-leg variants	3 sets, top reps	Bike + brief flat-ground walk-runs	≤2/10; 24h return
8	Reassess. Add running back if pain-free week 7	Maintenance set	Test return-to-run protocol	0–2/10

Phase 3: Build the Prevention Layer (Ongoing)

Most knee pain comes back. The work in Phase 3 is what prevents it.

Two pieces matter here, and only one of them is exercise.

Strength maintenance — once a week is the floor

Drop hip and knee work entirely after week 8 and the strength gains begin to wash out within weeks. The minimum effective dose for maintaining the gains from Phase 2 is one weekly session that touches the major movement patterns — single-leg work, hip hinge, hip abduction, calf — at moderate-to-high intensity. Two sessions is better. Most of this can be folded into existing strength training.

A useful add-on for runners and strength athletes: single-leg Romanian deadlifts, walking lunges, and a banded side-step series. These keep the gluteus medius firing under dynamic load, which is the function it most needs in real-world running, hiking, and stair-climbing.

Mobility — keep ankles and hip flexors honest

Two specific restrictions show up over and over in clinical assessments of recurrent knee pain: limited ankle dorsiflexion and tight hip flexors from prolonged sitting. Limited ankle dorsiflexion forces the knee forward and inward in squatting and landing patterns; tight hip flexors inhibit the glutes (the same mechanism that drove Phase 2’s hip emphasis). Five minutes a day on ankle dorsiflexion stretches and a half-kneeling hip flexor stretch is enough — there’s no need for a 30-minute mobility ritual.

The under-discussed lever: training load

The single best predictor of knee pain in active people is not how strong they are or how much they stretch — it’s how fast they’re ramping their training load.

This is where most well-rehabbed knees end up flaring again. The runner finishes Phase 2 pain-free, gets excited, and goes from 10 miles a week to 25 miles in two weeks. Two weeks later, the lateral knee pain is back.

The acute:chronic workload ratio (ACWR) is the framework that quantifies this risk. Acute load is what you’ve done in the last 7 days. Chronic load is your rolling 28-day average. The ratio of the two indicates whether you’re building gradually (safe) or spiking (risky).

Maupin and colleagues’ 2020 systematic review in Open Access Journal of Sports Medicine reviewed 27 studies on ACWR and injury risk and found that ratios in roughly the 0.8–1.3 range were consistently associated with the lowest injury risk, while ratios above 1.5 were associated with substantially elevated injury risk in many of the included studies — in some cohorts as much as a two- to four-fold increase.¹³ The Damsted 2018 systematic review in the International Journal of Sports Physical Therapy reached a complementary conclusion specifically for runners: sudden changes in training load were associated with increased running-related injury risk in three of the four eligible studies.¹⁴

Bryan Heiderscheit, PT, PhD, who runs the UW–Madison Runners’ Clinic and has published extensively on running biomechanics and load progression, has long argued that running cadence and weekly mileage progression are two of the most modifiable risk factors for running-related knee injuries. The practical translation: don’t build mileage faster than your tissue can adapt, and don’t change cadence by more than ~5–10% at a time.

Here’s the sharp edge of it. ACWR isn’t a number you can eyeball. It requires actual day-by-day training load data — duration, intensity, and ideally heart rate or perceived exertion — rolled into 7-day and 28-day averages. SensAI computes acute and chronic load directly from the wearable data your watch is already producing and adjusts the next session before the ACWR crosses 1.5. If you’re starting back to running specifically, our adaptive ramp-rate framework walks through this exact mechanic, and our couch-to-5K guide provides a beginner-safe ramp pattern that keeps the ratio in the safe zone by design.

The 2024 Neal et al. BJSM best-practice guide for PFP put this directly: load management belongs alongside strengthening as a core treatment pillar, not a footnote.¹²

Myths and What NOT to Do

A handful of bad ideas keep circulating. Each one keeps people stuck.

“Squatting past 90 degrees is bad for your knees.” Not in a healthy joint. Deep squatting under controlled load is associated with stronger, more resilient knees, not weaker ones. The phase-appropriate caveat: during a PFP flare, deep squat ranges may be temporarily provocative — that’s a Phase 1 issue, not a permanent rule.

“Running ruins your knees.” The 2017 JOSPT systematic review and meta-analysis by Alentorn-Geli and colleagues, pooling 25 studies with over 125,000 individuals, reached the opposite conclusion: recreational runners had significantly lower hip and knee osteoarthritis prevalence (3.5%) than sedentary controls (10.2%).¹⁵ The risk profile shifted only at competitive/elite volumes. For most readers, running is protective, not destructive.

“You need to selectively activate the VMO.” The idea that you can train the medial portion of the quadriceps in isolation has been challenged repeatedly in the EMG literature, and the JOSPT clinical practice guideline does not recommend interventions targeted at selective VMO activation as a primary treatment.² Train the quad as a whole, build hip control, and the knee tracks better.

“Foam rolling fixes the IT band.” The IT band is a tendinous structure that doesn’t meaningfully change length under foam roller pressure. The pain associated with rolling it comes from the deep tissue beneath it — and pain is not therapy. If foam rolling helps you tolerate work afterward, fine. If it’s your treatment plan for ITBS, you’re treating the symptom and ignoring the hip.⁶⁸

“Rest is the cure.” Complete rest is what creates Phase 0 problems. Tissue de-loads, muscles atrophy, and the moment you return to activity, you’re more vulnerable than when you started. Relative rest — modified, pain-managed loading — is the evidence-based answer.²⁴

When to See a Clinician

Most non-traumatic knee pain responds to the protocol above. Some doesn’t. See a sports physical therapist or sports medicine physician if:

• You hit two consecutive Phase 1 sessions where pain breaks the 3/10 rule or rebounds the next day
• You’ve completed Phase 2 and pain hasn’t reduced by ≥50% by week 6
• The knee gives way, catches, or locks during normal activity
• You develop new swelling, warmth, or pain at rest
• You’re returning from a surgical procedure (this guide is for non-surgical pain only)
• You’re a competitive athlete with a season-defining decision in front of you

Hands-on assessment can identify motor control deficits — exactly which way the femur drops, exactly when the hip abductors fail under fatigue — that no app or article can fully diagnose.

A 6-Week Snapshot

Week	Focus	Hip Day (2x)	Knee Day (1x)	Total Weekly Volume	Pain Threshold
1	Phase 1 calm-down	—	Quad isometrics, SLR, clamshell daily	5 short sessions	≤3/10; 24h return
2	Phase 1 → 2 transition	1 hip day, base reps	1 short knee day	3 sessions	≤3/10; 24h return
3	Phase 2 base	Glute bridge, side-lying ABD, clamshell	Spanish squat, step-down, TKE	3 sessions, 25 min	≤3/10; 24h return
4	Single-leg progression	Add single-leg bridge, side plank w/ ABD	Increase step-down depth	3 sessions, 30 min	≤3/10; 24h return
5	Add load	Banded clamshell, ankle-weighted ABD, step-up	Add load to Spanish squat	3 sessions, 30 min	≤2/10 during
6	Pre-return-to-run	Single-leg RDL, full hip menu	Maintenance knee work	3 sessions + walk-run	≤2/10 during
7	Return-to-run test	Maintain	Maintain	Add short, flat run intervals	0–2/10 during/after
8	Phase 3 maintenance	1–2 weekly sessions	Folded into strength day	Build mileage at ACWR ≤1.3	0–1/10

The Knee Is Honest — Listen to It

The knee is one of the most honest joints in the body. It tells you exactly when load has outpaced capacity and exactly when capacity is rebuilding. The mistake almost everyone makes is treating its complaint as a local problem and chasing the symptom with stretches, ice, braces, and rest. The knee is downstream. The treatable signal is upstream — at the hip, the calf, and most of all in how fast you’re loading the system relative to its current chronic capacity.

Three phases. Calm it down. Strengthen the whole chain. Match load to recovery. The protocol is the easy part. The discipline is keeping the load matched to recovery week after week, year after year — which is exactly the running pattern SensAI is designed to enforce: a six-week plan that becomes a six-month, then six-year, habit of progressive, pain-aware training.

Train the chain. Respect the load. The knee will keep up its end of the deal.

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References

Footnotes

1. Khayambashi K, Fallah A, Movahedi A, Bagwell J, Powers C. “Posterolateral hip muscle strengthening versus quadriceps strengthening for patellofemoral pain: a comparative control trial.” Archives of Physical Medicine and Rehabilitation, 2014;95(5):900-907. https://pubmed.ncbi.nlm.nih.gov/24440362/ ↩ ↩² ↩³

2. Willy RW, Hoglund LT, Barton CJ, Bolgla LA, Scalzitti DA, Logerstedt DS, Lynch AD, Snyder-Mackler L, McDonough CM. “Patellofemoral Pain: Clinical Practice Guidelines Linked to the International Classification of Functioning, Disability and Health From the Academy of Orthopaedic Physical Therapy of the American Physical Therapy Association.” Journal of Orthopaedic & Sports Physical Therapy, 2019;49(9):CPG1-CPG95. https://pubmed.ncbi.nlm.nih.gov/31475628/ ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷

3. Khayambashi K, Mohammadkhani Z, Ghaznavi K, Lyle MA, Powers CM. “The effects of isolated hip abductor and external rotator muscle strengthening on pain, health status, and hip strength in females with patellofemoral pain: a randomized controlled trial.” Journal of Orthopaedic & Sports Physical Therapy, 2012;42(1):22-29. https://pubmed.ncbi.nlm.nih.gov/22027216/ ↩ ↩²

4. Crossley KM, Stefanik JJ, Selfe J, Collins NJ, Davis IS, Powers CM, McConnell J, Vicenzino B, Bazett-Jones DM, Esculier JF, Morrissey D, Callaghan MJ. “2016 Patellofemoral pain consensus statement from the 4th International Patellofemoral Pain Research Retreat, Manchester. Part 1.” British Journal of Sports Medicine, 2016;50(14):839-843. https://pubmed.ncbi.nlm.nih.gov/27343241/ ↩ ↩² ↩³

5. Fredericson M, Cookingham CL, Chaudhari AM, Dowdell BC, Oestreicher N, Sahrmann SA. “Hip abductor weakness in distance runners with iliotibial band syndrome.” Clinical Journal of Sport Medicine, 2000;10(3):169-175. https://pubmed.ncbi.nlm.nih.gov/10959926/ ↩ ↩² ↩³

6. van der Worp MP, van der Horst N, de Wijer A, Backx FJ, Nijhuis-van der Sanden MW. “Iliotibial band syndrome in runners: a systematic review.” Sports Medicine, 2012;42(11):969-992. https://pubmed.ncbi.nlm.nih.gov/22994651/ ↩ ↩² ↩³ ↩⁴

7. Collins NJ, Barton CJ, van Middelkoop M, Callaghan MJ, Rathleff MS, Vicenzino BT, Davis IS, Powers CM, Macri EM, Hart HF, de Oliveira Silva D, Crossley KM. “2018 Consensus statement on exercise therapy and physical interventions (orthoses, taping and manual therapy) to treat patellofemoral pain: recommendations from the 5th International Patellofemoral Pain Research Retreat, Gold Coast, Australia, 2017.” British Journal of Sports Medicine, 2018;52(18):1170-1178. https://pubmed.ncbi.nlm.nih.gov/29925502/ ↩

8. Beers A, Ryan M, Kasubuchi Z, Fraser S, Taunton JE. “Effects of Multi-modal Physiotherapy, Including Hip Abductor Strengthening, in Patients with Iliotibial Band Friction Syndrome.” Physiotherapy Canada, 2008;60(2):180-188. https://pubmed.ncbi.nlm.nih.gov/20145781/ ↩ ↩² ↩³ ↩⁴

9. Nascimento LR, Teixeira-Salmela LF, Souza RB, Resende RA. “Hip and Knee Strengthening Is More Effective Than Knee Strengthening Alone for Reducing Pain and Improving Activity in Individuals With Patellofemoral Pain: A Systematic Review With Meta-analysis.” Journal of Orthopaedic & Sports Physical Therapy, 2018;48(1):19-31. https://pubmed.ncbi.nlm.nih.gov/29034800/ ↩

10. Lack S, Barton C, Sohan O, Crossley K, Morrissey D. “Proximal muscle rehabilitation is effective for patellofemoral pain: a systematic review with meta-analysis.” British Journal of Sports Medicine, 2015;49(21):1365-1376. https://pubmed.ncbi.nlm.nih.gov/26175019/ ↩

11. Powers CM. “The influence of abnormal hip mechanics on knee injury: a biomechanical perspective.” Journal of Orthopaedic & Sports Physical Therapy, 2010;40(2):42-51. https://pubmed.ncbi.nlm.nih.gov/20118526/ ↩

12. Neal BS, Lack SD, Bartholomew C, Morrissey D. “Best practice guide for patellofemoral pain based on synthesis of a systematic review, the patient voice and expert clinical reasoning.” British Journal of Sports Medicine, 2024;58(24):1486-1495. https://pubmed.ncbi.nlm.nih.gov/39401870/ ↩ ↩²

13. Maupin D, Schram B, Canetti E, Orr R. “The Relationship Between Acute:Chronic Workload Ratios and Injury Risk in Sports: A Systematic Review.” Open Access Journal of Sports Medicine, 2020;11:51-75. https://pubmed.ncbi.nlm.nih.gov/32158285/ ↩

14. Damsted C, Glad S, Nielsen RO, Sørensen H, Malisoux L. “Is There Evidence for an Association Between Changes in Training Load and Running-Related Injuries? A Systematic Review.” International Journal of Sports Physical Therapy, 2018;13(6):931-942. https://pubmed.ncbi.nlm.nih.gov/30534459/ ↩

15. Alentorn-Geli E, Samuelsson K, Musahl V, Green CL, Bhandari M, Karlsson J. “The Association of Recreational and Competitive Running With Hip and Knee Osteoarthritis: A Systematic Review and Meta-analysis.” Journal of Orthopaedic & Sports Physical Therapy, 2017;47(6):373-390. https://pubmed.ncbi.nlm.nih.gov/28504066/ ↩