Pain around the kneecap on stairs, or on the outer side of the knee after a few kilometers: in runners, the knee is the most frequently injured area. In a review of 42 studies, it accounted for 31.2% of reported injuries, and patellofemoral syndrome, commonly called runner's knee, ranked first among diagnoses at 16.7% of injuries, ahead of iliotibial band syndrome, known as IT band syndrome (7.9%).
This guide brings together what studies identified via PubMed show: recognizing both syndromes, their risk factors, exercises recommended by international consensus, load management, cadence, insoles and taping, medical options and trials on collagen, followed by a 12-week return-to-running protocol.
Runner's knee : pain is located around or behind the kneecap. The standard treatment combines hip and knee strengthening with load adjustment: in 69 runners, an education program focused on training produced progress comparable, with no significant difference, to the addition of exercises or gait retraining. Increasing cadence by 10% reduces force on the kneecap by 14%; insoles provide short-term relief, taping has a weak and uncertain effect, and arthroscopy offers nothing more than exercises.
IT band syndrome and collagen : pain is located on the outer side of the knee; in a series without a control group, 22 out of 24 runners had no pain after 6 weeks of hip abductor strengthening. An injection provides short-term relief, and a platelet-rich plasma injection performed better than placebo in resistant cases. In athletes, 5 to 10 g of collagen daily for 12 to 24 weeks modestly reduced knee pain during activity.
- Runner's knee: leading cause of knee pain in runners
- Runner's knee or IT band syndrome: recognizing the pain
- Causes and risk factors: load before morphology
- Exercises for runner's knee: the hip and knee
- Adjust load rather than stop everything
- Cadence: 5 to 10% more steps
- Knee brace, taping and insoles: short-term support
- IT band syndrome: treatment
- When to consult: injections, PRP, surgery
- Collagen and knee pain during activity
- Return to running: the 12-week protocol
- Frequently asked questions
Patellofemoral pain syndrome: the leading cause of runner's knee pain
In the review of 42 studies cited above, 3,222 of the 10,941 runners followed in 18 prospective studies were injured, an average of 40.2% per study. Among the 10,640 injuries diagnosed in retrospective studies, femoropatellar syndrome ranked first with 16.7%, ahead of tibial stress syndrome, plantar fasciitis, and iliotibial band syndrome: it is the leading cause of knee pain in running. In prospective studies, it ranks third (6.3%), behind Achilles tendinopathy and tibial stress syndrome. Across all activities, it represents 25 to 40% of knee problems seen in sports medicine, according to the 2016 international consensus.
These experts adopt the term femoropatellar pain, synonymous with patellar chondromalacia, anterior knee pain, and runner's knee; in France, patellofemoral pain syndrome is used. The joint involved, between the kneecap and femur, works with each step on a bent knee.
Among 1,525 students at the U.S. Naval Academy followed for up to two and a half years, femoropatellar pain syndrome appeared at a rate of 22 cases per 1,000 person-years. Women had 2.23 times greater risk of developing it than men.
Boling M, Padua D, Marshall S, et al. Scand J Med Sci Sports 2010;20(5):725-730. DOI : 10.1111/j.1600-0838.2009.00996.x
The iliotibial band syndrome, or iliotibial band friction syndrome, is the most common injury on the outer aspect of the runner's knee, with an incidence of 5 to 14% according to a systematic review, and up to 16% of running injuries according to a 2026 review. Both syndromes partly respond to the same interventions: training load, hip and knee strength, running mechanics.
Patellofemoral pain syndrome or iliotibial band syndrome: recognizing the pain
According to consensus, patellofemoral pain syndrome is defined by pain around or behind the kneecap, triggered by at least one activity that loads the bent knee: squatting, stairs, running, jumping. Crepitus, tenderness at the kneecap edges, mild effusion, or pain after prolonged sitting may accompany it. No single test suffices: when squatting triggers pain, the syndrome is present in 80% of cases, and when palpation of the kneecap edges is painful, in 71 to 75%; the Clarke test, which compresses the kneecap, has low sensitivity.
Iliotibial band syndrome causes pain on the outer aspect of the knee, at the level of the lateral femoral epicondyle, and worsens as running continues. Its name evokes a band that would rub against bone with each bend. In a study of 15 cadavers supplemented by MRI, it was anchored to the femur without a bursa, and a richly innervated fat layer, compressed around 30 degrees of flexion, appeared to be the culprit.
| Criterion | Patellofemoral pain syndrome | Iliotibial band syndrome |
|---|---|---|
| Location | Around or behind the kneecap | Outer aspect, at the level of the lateral epicondyle |
| Triggers | Squatting, stairs, running, jumping, prolonged sitting | Running, increasingly painful as it continues |
| Associated signs | Crunching, kneecap edges tender, slight effusion | Local sensitivity, positive provocation tests |
| Best indicator | Pain with squatting: syndrome present in 80% of positive tests | Clinical examination, imaging if in doubt |
| Probable mechanism | Overload of the joint between kneecap and femur | Compression of innervated fat under the iliotibial band |
| First-line treatment | Hip and knee exercises, load management | Active rehabilitation, hip abductors |
A history of kneecap dislocation requires different management, according to consensus. On the outer side, pain can also come from the lateral meniscus, a collateral ligament, cartilage, bone edema, or the biceps femoris tendon, notes the 2026 review. Our guide to joint pain reviews other causes.
Causes and risk factors: load before morphology
Prospective studies, which measure suspected factors before pain appears, challenge several common beliefs.
Among 4,818 participants followed—military recruits, adolescents, and recreational runners—483 developed patellofemoral syndrome. Age, height, weight, body mass index, body fat, and Q angle did not predict its occurrence. Quadriceps weakness was a risk factor in military recruits (effect size of −0.69), hip weakness was not.
Neal BS, Lack SD, Lankhorst NE, et al. Br J Sports Med 2019;53(5):270-281. DOI: 10.1136/bjsports-2017-098890
An effect size compares the difference between two groups relative to the spread of measurements. By convention, 0.2 corresponds to a small effect, 0.5 to a medium effect, and 0.8 to a large effect; the sign indicates only the direction of the difference: −0.69 thus corresponds to a medium effect.
Training progression is another lead. Among 874 beginning runners followed for one year with GPS watches, those who increased their weekly distance by more than 30% had 1.59 times more distance-related injuries, including patellofemoral syndrome and iliotibial band syndrome, than those who progressed by less than 10%. The difference was not statistically significant, but the authors advise beginners not to exceed 30% increase over two weeks.
For iliotibial band syndrome, one study analyzed the gait of healthy female runners then followed them for two years: the 18 who developed the syndrome had from the start greater hip adduction, the thigh turning inward, and greater internal knee rotation than comparable runners. These are associations, not demonstrated causes, but they guide rehabilitation toward hip control.
Exercises for patellofemoral syndrome: hip and knee
The 2015 Cochrane review gathered 31 trials and 1,690 participants. Compared to a control group, exercises reduced exertional pain by 1.46 points on a 10-point scale, around the 1.3-point threshold considered clinically important, and markedly improved function (effect size of 1.10); at one year, the estimate was 88 additional people recovered per 1,000, with substantial uncertainty (2 fewer to 210 more). The evidence is of very low quality, but consistent.
Adding hip work was better: adding hip exercises reduced exertional pain by an additional 2.20 points compared to knee exercises alone. The 2016 and 2018 consensus statements recommend exercise, regardless of type, and combining hip and knee work preferably to knee work alone. The fundamentals of strengthening are detailed in our guide for building muscle.
In 54 sedentary women aged 20 to 40, four weeks of knee stretching and strengthening, supplemented by strengthening the abductors, external rotators, and hip extensors, reduced pain and improved function more at 3, 6, and 12 months than knee work alone. On a lower limb function scale, the difference still reached 20.8 points at one year.
Fukuda TY, Melo WP, Zaffalon BM, et al. J Orthop Sports Phys Ther 2012;42(10):823-830. DOI: 10.2519/jospt.2012.4184
In a double-blind trial of 79 people, eight weeks of leg press and leg extension at 30% of maximum load, with a blood flow restriction cuff, reduced daily pain 93% more than the same work at 70% without a cuff; at six months, the groups no longer differed. The 2018 consensus judges it uncertain, and it is practiced under supervision by a trained professional.
Adapt the load rather than stop everything
In runners, knowing how much to run is part of the treatment.
In 69 runners with patellofemoral pain syndrome, eight weeks of education on symptom management and training modification improved pain and function with no significant difference compared to the same education supplemented with exercises or gait retraining at 4, 8, and 20 weeks. Gait retraining increased cadence by 7% and reduced loading rate at impact by 25.4%, without additional benefit on symptoms.
Esculier JF, Bouyer LJ, Dubois B, et al. Br J Sports Med 2018;52(10):659-666. DOI: 10.1136/bjsports-2016-096988
The authors made education on symptoms and load a central element of treatment. Three months after the program, 78% of the 58 runners analyzed (approximately 20 km per week) had significantly improved; function score, knee extension strength, usual pain, and patellar tendinopathy, addressed in our article on recurrent tendinitis, together predicted outcome in 87.9% of cases.
In 151 adolescents aged 10 to 14 years, four weeks of activity modification guided by an activity scale and pain monitoring, followed by four weeks of exercises and four weeks of return to sport, yielded 86% favorable results at 12 weeks and 81% at one year, in a study without a control group.
Early action matters. In 310 people followed in two trials, 40% still had an unfavorable course at one year, regardless of treatment, and pain lasting more than two months was the most consistent poor prognostic factor. Five to eight years later, 57% of the 60 respondents did not consider themselves significantly recovered, with no visible osteoarthritis on 48 of 50 radiographs.
Fear of movement is moderately associated with poorer function, according to a review of 41 studies involving 2,712 people. If pain is accompanied by persistent fatigue, our article on fatigue and overtraining helps clarify the overall training load.
Cadence: 5 to 10% more steps
Cadence is the number of steps per minute. At equal speed, increasing it shortens the stride and brings the foot strike closer to the center of gravity. In 45 runners at 172.6 steps per minute on average, an increase of 5 to 10% reduced the energy absorbed by the knee at each footstrike as well as hip adduction, and a model applied to 30 adults showed a 14% reduction in force on the patella with 10% more steps.
| Modification | Measured Effect | Study |
|---|---|---|
| Cadence +5%, 45 runners | Approximately 20% less energy absorbed by the knee | Heiderscheit, 2011 |
| Cadence +10%, 45 runners | Approximately 34% less energy absorbed by the knee | Heiderscheit, 2011 |
| Cadence +10%, 30 adults | −14% maximum force on the patellofemoral joint | Lenhart, 2014 |
| Downhill at 6 degrees, 20 runners | Higher stress on the patella than on flat or uphill running | Ho, 2018 |
| Cadence +10%, 12 injured runners | +15 km per week and +9.3 km pain-free at 3 months | Bramah, 2019 |
| Cadence +7%, randomized trial | No improvement in symptoms compared to education alone | Esculier, 2018 |
Twelve runners suffering from patellofemoral pain syndrome, with pelvic tilt or excessive hip adduction, received a single gait retraining session: increasing their cadence by 10% using a metronome, then monitoring it themselves with a GPS watch. Three months later, their pain and function had improved, and their longest pain-free run had increased from 2 to 11.3 km.
Bramah C, Preece SJ, Gill N, Herrington L. Am J Sports Med 2019;47(14):3406-3413. DOI: 10.1177/0363546519879693
These results remain to be confirmed: a review of 37 studies considers evidence of an effect on pain and function very limited, and the 2018 consensus classifies gait training among uncertain options. Cadence is therefore a simple mechanical lever to try when running remains painful, rather than a treatment in itself.
Count your right foot strikes for 30 seconds at your usual pace, and multiply by four. Aim for 5 to 10% more at the same speed, using a metronome or watch. Downhill, where stress on the kneecap increases, lean your torso slightly more forward, as suggested by the authors of the study conducted on 20 runners.
Knee brace, taping and insoles: short-term support
Prefabricated orthopedic insoles are the most studied. In 179 adults aged 18 to 40, six weeks of insoles performed better than flat insoles, with additional improvement for 4 people fitted, with no significant difference from physical therapy, and no added benefit to it; all groups showed marked improvement at one year. The 2016 consensus recommends them for short-term use, particularly when pain decreases immediately during a single-leg squat with the insole.
For kinesiology taping, a meta-analysis of 10 trials finds a pain reduction of 0.58 points on a 10-point scale when added to rehabilitation, a weak effect. According to a review of 45 trials, adding taping or a knee brace to exercises does not perform better than exercises alone, based on very low certainty evidence; another review suggests, based on very low certainty evidence, that these aids reduce fear of movement just after application.
| Medium | What the studies show | Place |
|---|---|---|
| Prefabricated insoles | Better than flat insoles at 6 weeks, nothing more than physical therapy | Short-term relief |
| Kinesiology taping | −0.58 points of pain on a 10-point scale added to rehabilitation | Uncertain option |
| Knee brace or strap | No added benefit to exercises, fear of movement reduced just after application (very low certainty evidence) | Occasional aid |
| Mobilizations alone | No demonstrated improvement | Not recommended |
| Electrotherapy | Small effect added to exercises, very low certainty evidence | Not recommended by consensus guidelines |
Iliotibial band syndrome: treatment
If the band doesn't rub, stretching it makes little sense: in an anatomical study, its lengthening remained less than 0.5%, and its junction with the tensor fasciae latae muscle moved only 2 mm during hip abduction in 20 volunteers. The authors propose targeting the muscular portion instead.
In 24 long-distance runners suffering from iliotibial band syndrome, hip abduction strength was weaker on the affected side than on the healthy side and than in 30 unaffected runners. After six weeks of rehabilitation focused on the gluteus medius, it increased by 34.9% in women and 51.4% in men; 22 out of 24 runners no longer experienced pain and had resumed running, with no recurrence at six months.
Fredericson M, Cookingham CL, Chaudhari AM, et al. Clin J Sport Med 2000;10(3):169-175. DOI: 10.1097/00042752-200007000-00004
This series had no control group, and the 2012 systematic review considers the evidence weak and contradictory, but emphasizes hip and knee coordination and running style as key elements, with possible benefit from hip strengthening. The 2026 review (24 studies, 1,012 patients) makes active rehabilitation the first-line treatment; one study found no effect of foam rolling or stretching compared to no intervention.
Regarding stride, in 15 healthy runners, foot strikes closer to the body's axis increased band tension, while more spaced-out strikes reduced it. Increasing cadence by 5 to 10% further reduces hip adduction, the movement associated with the syndrome in female runners followed for two years.
When to consult: injections, PRP, surgery
If discomfort does not improve after two months despite appropriate training load, consult a sports medicine physician or physiotherapist, and without delay in case of trauma, swelling, locking, giving way, fever, or night pain.
For patellofemoral pain syndrome, surgery has not proven effective: in 56 patients with chronic disease, arthroscopy added to eight weeks of home exercises did not perform better than exercises alone at nine months, with 12.9 points of functional score gained versus 11.4, at an additional cost of 901 euros per patient.
For iliotibial band syndrome, in 18 runners with symptoms for less than two weeks, an injection of 40 mg of methylprednisolone with an anesthetic reduced running pain by 53.6% in two weeks, versus 20.3% with anesthetic alone. In forms resistant to 12 weeks of treatment, the 2026 review describes a double-blind trial of 60 patients: an ultrasound-guided platelet-rich plasma injection reduced pain by 4.7 points at six months, versus 2.5 with saline, and 83.3% of patients resumed their sport, versus 56.7%. Surgery, reserved for failures, has only been evaluated in six studies without a control group, where reported satisfaction and return-to-sport rates exceeded 84%.
Injection has only been evaluated over 14 days, platelet-rich plasma in a single trial that remains to be replicated, and surgery in studies without a control group. These options complement hip rehabilitation and load management, they do not replace them.
Collagen and knee pain with activity
Two randomized trials tested collagen peptides for knee pain in athletes.
In 139 young athletes with activity-related knee pain, 5 g of collagen peptides per day for 12 weeks reduced exertional pain by 19.5 points, versus 13.9 with placebo, a result confirmed by physician assessment. Pain at rest did not differ significantly between groups, and the use of other treatments decreased with collagen.
Zdzieblik D, Oesser S, Gollhofer A, König D. Appl Physiol Nutr Metab 2017;42(6):588-595. DOI: 10.1139/apnm-2016-0390
In a 24-week trial of 147 athletes from university teams or clubs, 10 g of collagen hydrolysate per day reduced running pain by 1.50 points, versus 0.80 under placebo, in the subgroup of 63 athletes with knee pain; only 97 of 147 participants were analyzed. In eight men, finally, 15 g of gelatin enriched with vitamin C taken one hour before six minutes of rope jumping doubled a blood marker of collagen synthesis, a short trial that does not measure pain; our article when to take collagen details this question.
These effects remain modest, and no trial has been conducted on runners with patellofemoral pain syndrome or iliotibial band syndrome: collagen should be considered as a complement to rehabilitation, over several months. Our Marine collagen powder provides 10 g of type 1 marine collagen per measuring spoon, with 210 mg of hyaluronic acid and 80 mg of vitamin C. Our articles on marine collagen dosage and on collagen and joints complement this topic.
Returning to running: the 12-week protocol
This protocol brings together the parameters from the cited studies: three-phase structure of the 12-week program, load education, exercises from randomized trials, and cadence increase. It applies to both syndromes, without warning signs, and a physiotherapist can adapt it to your case.
For next steps, our guides for preparing a marathon or a trail race detail a complete training progression.
Stop and consult if you experience swelling, locking, knee giving way or night pain. Blood flow restriction cuffs must be used under supervision, infiltrations and injections require a doctor's care, and marine collagen should be avoided if you have a fish allergy. In adolescents, the tested program included four sessions with a physical therapist in the presence of parents.
Hydrolyzed type 1 marine collagen Naticol®, patented, with neutral taste. One measuring scoop provides 10 g of type 1 marine collagen, 210 mg of hyaluronic acid and 80 mg of vitamin C daily, to be dissolved in water, juice, yogurt or a shaker; a 300 g jar lasts one month.
View Marine CollagenOur complete guide to marine collagen details its forms, dosages and what the research says.
Frequently asked questions
What is patellofemoral pain syndrome?
Pain around or behind the kneecap, aggravated by activities that load the bent knee: running, stairs, squatting, jumping. Experts call it patellofemoral pain, also known as runner's knee. It is the leading diagnosis in retrospective studies on runner injuries, accounting for 16.7% of injuries.
What are the symptoms of patellofemoral pain syndrome?
Often diffuse pain at the front of the knee, triggered by squatting, stairs, running or prolonged sitting, sometimes accompanied by cracking or slight effusion. When squatting triggers pain, the syndrome is present in 80% of cases.
What is the difference between patellofemoral pain syndrome and IT band syndrome?
Patellofemoral pain syndrome causes pain at the front of the knee, around or behind the kneecap. Iliotibial band syndrome causes pain on the outside, at the level of the lateral femoral epicondyle, and worsens as running continues; it appears to be linked to compression of tissues under the iliotibial band rather than friction.
How long does patellofemoral pain syndrome last?
It can last: in two trials involving 310 people, 40% still had unfavorable progression at one year. Pain lasting more than two months is the primary factor for poor prognosis, hence the importance of acting early. With a load management program, 78% of runners in one trial were significantly better three months later.
Can you continue running with patellofemoral pain syndrome?
The studied programs are based on load adaptation rather than complete rest: reducing or splitting runs, temporarily avoiding descents, then gradually returning by stages. In 69 runners, eight weeks of education on symptom and training management produced comparable progress, with no significant difference, to adding exercises or gait work.
What exercises help treat patellofemoral pain syndrome?
Knee strengthening, notably of the quadriceps, combined with strengthening of the abductors, external rotators and hip extensors—an association that international consensus prefers to knee exercises alone. In 54 women, four weeks of this program reduced pain and improved function for up to one year.
Should you wear a knee brace for patellofemoral pain syndrome?
It's not essential: according to a review of 45 trials, adding a knee brace or taping to exercises performs no better than exercises alone, based on very low certainty evidence. Another review suggests, based on very low certainty evidence, that these aids reduce fear of movement just after application.
Does taping relieve patellofemoral pain syndrome?
Somewhat, in the short term: a meta-analysis of 10 trials on kinesiology taping found a pain reduction of 0.58 points on a 10-point scale when added to rehabilitation. The 2018 consensus classifies it among uncertain options, to be used to complement exercises, depending on tolerance.
Which sports are discouraged with patellofemoral pain syndrome?
No sport is inherently forbidden: it's the movements that load the kneecap on a bent knee that trigger pain—squatting, jumping, stairs, running and especially descents. The studied programs dose these rather than eliminate them, reintroducing them by stages.
How do you treat iliotibial band syndrome?
With active rehabilitation as a priority: hip abductor strengthening and running adaptation. In a series of 24 runners, 22 had returned to running pain-free after six weeks of gluteus medius strengthening, without a control group. In healthy runners, slightly widening stride width reduces iliotibial band stretch, and increasing cadence reduces hip adduction.
Is an injection useful for iliotibial band syndrome?
It can provide short-term relief: in 18 runners, a corticosteroid injection reduced running pain by 53.6% in two weeks, versus 20.3% with anesthetic alone. In cases resistant for more than 12 weeks, platelet-rich plasma injection performed better than placebo in a trial of 60 patients.
Does collagen help with knee pain?
Trials in athletes show a modest effect: with 5 g of collagen peptides daily for 12 weeks, pain on exertion decreased by 19.5 points compared to 13.9 with placebo in 139 young athletes, and 10 g daily for 24 weeks reduced running pain more than placebo. It complements rehabilitation without replacing it.
Sources
The studies cited below were identified via PubMed.
- Kakouris N, Yener N, Fong DTP. Systematic review of running-related musculoskeletal injuries in runners. Journal of Sport and Health Science, 2021;10(5):513-522. DOI
- Crossley KM, van Middelkoop M, Callaghan MJ, et al. 2016 Consensus on patellofemoral pain, 4th International Patellofemoral Pain Research Retreat, Manchester. Part 2: Recommended physical interventions (exercise, taping, braces, insoles and combined interventions). British Journal of Sports Medicine, 2016;50(14):844-852. DOI
- Crossley KM, Stefanik JJ, Selfe J, et al. 2016 Consensus on patellofemoral pain, 4th International Patellofemoral Pain Research Retreat, Manchester. Part 1: Terminology, definitions, clinical examination, natural history, patellofemoral osteoarthritis and patient-reported measures. British Journal of Sports Medicine, 2016;50(14):839-843. DOI
- Boling M, Padua D, Marshall S, et al. Sex differences in incidence and prevalence of patellofemoral pain syndrome. Scandinavian Journal of Medicine and Science in Sports, 2010;20(5):725-730. DOI
- van der Worp MP, van der Horst N, de Wijer A, et al. Iliotibial band syndrome in runners: a systematic review. Sports Medicine, 2012;42(11):969-992. DOI
- Ferrero A, Moro A, Minelli M, et al. Extreme diagnostic and therapeutic heterogeneity limits conclusions on the treatment of iliotibial band syndrome: systematic review with stratification of levels of evidence. Orthopedic Research and Reviews, 2026;18:629195. DOI
- Fairclough J, Hayashi K, Toumi H, et al. Functional anatomy of the iliotibial band during knee flexion and extension: implications for understanding iliotibial band syndrome. Journal of Anatomy, 2006;208(3):309-316. DOI
- Neal BS, Lack SD, Lankhorst NE, et al. Risk factors for patellofemoral pain: systematic review and meta-analysis. British Journal of Sports Medicine, 2019;53(5):270-281. DOI
- Nielsen RØ, Parner ET, Nohr EA, et al. Excessive progression of weekly distance and risk of running-related injuries: an association that varies by injury type. Journal of Orthopaedic and Sports Physical Therapy, 2014;44(10):739-747. DOI
- Noehren B, Davis I, Hamill J. Prospective study of biomechanical factors associated with iliotibial band syndrome. Clinical Biomechanics, 2007;22(9):951-956. DOI
- van der Heijden RA, Lankhorst NE, van Linschoten R, et al. Exercise in the treatment of patellofemoral pain syndrome. Cochrane Database of Systematic Reviews, 2015;1:CD010387. DOI
- Collins NJ, Barton CJ, van Middelkoop M, et al. 2018 Consensus on exercise and physical interventions (orthoses, taping and manual therapy) for 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. DOI
- Fukuda TY, Melo WP, Zaffalon BM, et al. Strengthening of posterolateral hip muscles in sedentary women with patellofemoral pain syndrome: randomized controlled trial with one-year follow-up. Journal of Orthopaedic and Sports Physical Therapy, 2012;42(10):823-830. DOI
- Giles L, Webster KE, McClelland J, Cook JL. Quadriceps strengthening with and without blood flow restriction in the treatment of patellofemoral pain: double-blind randomized trial. British Journal of Sports Medicine, 2017;51(23):1688-1694. DOI
- Esculier JF, Bouyer LJ, Dubois B, et al. Is gait retraining or an exercise program combined with education better than education alone in runners with patellofemoral pain? Randomized clinical trial. British Journal of Sports Medicine, 2018;52(10):659-666. DOI
- Esculier JF, Bouyer LJ, Dubois B, et al. Predictive factors for clinical success in runners with patellofemoral pain: secondary analyses of a randomized clinical trial. Journal of Science and Medicine in Sport, 2018;21(8):777-782. DOI
- Rathleff MS, Graven-Nielsen T, Hölmich P, et al. Activity modification and load management in adolescents with patellofemoral pain: prospective intervention study in 151 adolescents. The American Journal of Sports Medicine, 2019;47(7):1629-1637. DOI
- Collins NJ, Bierma-Zeinstra SMA, Crossley KM, et al. Prognostic factors for patellofemoral pain: multicenter observational analysis. British Journal of Sports Medicine, 2013;47(4):227-233. DOI
- Lankhorst NE, van Middelkoop M, Crossley KM, et al. Predictive factors for unfavorable outcomes 5 to 8 years after patellofemoral pain diagnosis: multicenter observational analysis. British Journal of Sports Medicine, 2016;50(14):881-886. DOI
- Rethman KK, Mansfield CJ, Moeller J, et al. Kinesiophobia is associated with worse function and is modifiable by interventions in people with patellofemoral pain: systematic review with meta-analysis of individual participant data correlations. Physical Therapy, 2023;103(9):pzad074. DOI
- Heiderscheit BC, Chumanov ES, Michalski MP, et al. Effects of cadence modification on joint mechanics during running. Medicine and Science in Sports and Exercise, 2011;43(2):296-302. DOI
- Lenhart RL, Thelen DG, Wille CM, et al. Increasing running cadence reduces patellofemoral forces. Medicine and Science in Sports and Exercise, 2014;46(3):557-564. DOI
- Ho KY, French T, Klein B, Lee Y. Patellofemoral stress during uphill and downhill running. Physical Therapy in Sport, 2018;34:136-140. DOI
- Bramah C, Preece SJ, Gill N, Herrington L. A 10% increase in cadence improves running kinematics and clinical outcomes in runners with patellofemoral pain at 4 weeks and 3 months. The American Journal of Sports Medicine, 2019;47(14):3406-3413. DOI
- Anderson LM, Martin JF, Barton CJ, Bonanno DR. What is the effect of running cadence modification on injury, performance, and biomechanics? Systematic review and meta-analysis. Sports Medicine - Open, 2022;8(1):112. DOI
- Collins N, Crossley K, Beller E, et al. Orthotic insoles and physiotherapy in the treatment of patellofemoral pain syndrome: a randomized clinical trial. BMJ, 2008;337:a1735. DOI
- Jiao H, Tao M, Cui X. Effects of kinesiology taping on pain and knee function in patellofemoral pain syndrome: a systematic review and meta-analysis. BMC Musculoskeletal Disorders, 2025;26(1):388. DOI
- Souto LR, De Oliveira Silva D, Pazzinatto MF, et al. Do adjunctive treatments improve pain and function when added to exercise in people with patellofemoral pain? Systematic review with meta-analysis and quality assessment of interventions. British Journal of Sports Medicine, 2024;58(14):792-804. DOI
- Falvey EC, Clark RA, Franklyn-Miller A, et al. Iliotibial band syndrome: an examination of the evidence behind several therapeutic options. Scandinavian Journal of Medicine and Science in Sports, 2010;20(4):580-587. DOI
- Fredericson M, Cookingham CL, Chaudhari AM, et al. Hip abductor weakness in distance runners with iliotibial band syndrome. Clinical Journal of Sport Medicine, 2000;10(3):169-175. DOI
- Meardon SA, Campbell S, Derrick TR. Step width alters iliotibial band tension during running. Sports Biomechanics, 2012;11(4):464-472. DOI
- Kettunen JA, Harilainen A, Sandelin J, et al. Knee arthroscopy and exercise versus exercise alone in chronic patellofemoral pain syndrome: a randomized controlled trial. BMC Medicine, 2007;5:38. DOI
- Gunter P, Schwellnus MP. Local corticosteroid infiltration in iliotibial band friction syndrome in runners: a randomized controlled trial. British Journal of Sports Medicine, 2004;38(3):269-272. DOI
- Zdzieblik D, Oesser S, Gollhofer A, König D. Improvement in activity-related knee joint discomfort following supplementation of specific collagen peptides. Applied Physiology, Nutrition, and Metabolism, 2017;42(6):588-595. DOI
- Clark KL, Sebastianelli W, Flechsenhar KR, et al. 24-week study on collagen hydrolysate as a dietary supplement in athletes with activity-related joint pain. Current Medical Research and Opinion, 2008;24(5):1485-1496. DOI
- Shaw G, Lee-Barthel A, Ross ML, et al. Supplementation with gelatin enriched in vitamin C before intermittent activity increases collagen synthesis. The American Journal of Clinical Nutrition, 2017;105(1):136-143. DOI
