Overload on the knee due to sports (running, jumping, squats)

Anatomy and loading mechanics: Why the knee reacts during sport

The knee joint transmits high forces between the hip and foot. When running, jumping and squatting, repeated load peaks affect the tendon attachments, kneecap (patella) and surrounding soft tissues. Tendons are sensitive to rapid increases in load: microdamage can develop into tendinopathy if there is insufficient recovery.

• Patellar tendon: Connects the kneecap and shinbone; heavily stressed during jumps and landings.
• Quadriceps tendon: transition from the anterior thigh muscle to the patella; relevant for squats and quick changes of direction.
• Pes anserinus (goose foot): tendon plate on the inside of the shinbone; irritated when running circumference increases or the foot is crooked.
• Hamstrings: Biceps femoris on the outside, semitendinosus/semimembranosus on the inside; stabilize and brake landings.
• Gastrocnemius (twin calf muscle): Involved in knee stability and take-off, especially the medial head.
• Popliteus: Small stabilizer in the back of the knee; important for rotation control when running.

In addition to the size of the load, technique, hip and trunk strength, ankle joint mobility and the quality of recovery breaks are also important biomechanically. An imbalance along the entire kinetic chain increases the stress on the knee.

Typical symptoms of sports-related knee strain

• Stress-dependent pain at the tendon attachments (in the front under the kneecap, above the patella, inside the shinbone, outside the knee).
• Pain when starting the session, often improves after warming up, then increases again later.
• Tenderness over the affected tendon, occasionally local swelling or warmth.
• stiffness in the morning or after sitting; Staircase pain or pain when running downhill.
• Loss of performance, unsteady feeling when landing, occasionally unpleasant “pulling” in the tendon.

Warning signs that can go beyond pure overuse include sudden snapping pain with loss of function, significant joint effusion, a feeling of blockage, instability or fever. These should be clarified by a doctor as soon as possible.

Common overload patterns when running, jumping and squatting

• Patellar tendinopathy (jumpers knee): Typical in jumps, sprints and box jumps; Pain below the kneecap.
• Quadriceps tendinopathy: Pain above the kneecap, increased with deep squats or lunges.
• Pes anserinus tendinitis/bursitis: tenderness on the inside of the shin just below the knee; more common when running circumference increases.
• Biceps femoris tendinitis: pain on the outside back of the knee, v. a. when running quickly or changing direction.
• Semimembranosus/Semitendinosus tendinopathy: Intra-posterior knee pain, often with pulling or braking stress.
• Gastrocnemius tendon irritation: pain at the back and top of the calf, landing pain, v. a. after jumping series.
• Popliteus tendinopathy: Deep pain in the back of the knee, worsening when running downhill or on sloping surfaces.
• Patellofemoral pain syndrome: Anterior knee pain without clear tendon involvement, especially a. downhill, stairs, sitting.

You can find more in-depth pages in our guide for several of these patterns; Below we link relevant detail pages.

Causes and risk factors of knee overuse

• Increase in load too quickly (volume, intensity, altitude, number of jumps) without sufficient regeneration.
• Technique factors: Collapsing knee inward (valgus), poor hip abductor strength, reduced trunk stability.
• Limited ankle joint mobility (dorsiflexion), compensatory higher patellar tendon load when squatting.
• Surface and shoes: Hard, sloping or uneven surfaces; worn footwear, poor cushioning/guidance.
• One-sided training without compensation (only running, no strength/stability program).
• Previous injuries or incorrect strain in the hip, pelvis, foot (leg axis check).
• Systemic factors: lack of sleep, stress, insufficient energy intake, smoking – impair tendon regeneration.

Diagnostics in practice: anamnesis, examination, imaging if necessary

The diagnosis of overload is primarily clinical. The decisive factors are the stress history, pain location, typical reinforcers and behavior during training. In our practice in Hamburg, we take a targeted anamnesis and examine the tendons, muscle chains and leg axis.

• Clinical tests: Palpation of the tendon attachments, functional and provocation tests (e.g. single-leg squat, hop tests).
• Movement control: Assessment of running or squatting technique, if appropriate.
• Ultrasound (sonography): visualization of the tendon, fluid, thickenings; dynamic assessment.
• MRI: In case of unclear findings, resistance to therapy, suspected partial tear or accompanying pathologies.
• Differential diagnoses: meniscus lesion, patellofemoral pain syndrome, bursitis, rarely stress reactions on the bone.

Imaging is not always necessary. It is used on a case-by-case basis if it has consequences for therapy.

Conservative therapy: evidence-based, structured and suitable for everyday use

The aim is to reduce tendon irritation and gradually rebuild resilience. Conservative is usually the first and most successful choice. The plan is individually adapted to pain, goals and everyday training routine.

Shock wave therapy (ESWT) can be used for some tendinopathies, e.g. B. the patellar tendon, can be considered as an option if basic therapy is not sufficient. Injections are used cautiously and based on indications: cortisone on tendons is usually not recommended for chronic tendinopathy; Platelet-rich plasma (PRP) may be considered in selected cases. We discuss opportunities and limitations transparently.

Return to Sport: Safely return to running, jumping and squats

The return will take place gradually based on criteria. The aim is to have a sufficiently resilient tendon, a stable leg axis and low-symptom stress in everyday and sports situations.

• Everyday criteria: Painless stairs, sitting and walking, no increase 24-48 hours later.
• Strength criteria: Close symmetry in the single leg quadriceps and hamstring tests, good calf strength levels.
• Jump criteria: Controlled landing without knee valgus in drop jumps/single-leg hops.
• Sport-specific: First technique drills at low intensity, then increase frequency/volume, intensity last.
• Monitoring: training and pain log; Increase load gradually (e.g. 5-10% per week).

Prevention: How to prevent overloading your knee

• Control your load wisely: moderately increase the amount and intensity, alternate hard and easy days.
• Warm-up and technique: Activate for 10-15 minutes, practice jumping and landing mechanics; Do not allow your knee to collapse inward.
• Maintain strength base: Lower body and core strength (quadriceps, glutes, hamstrings, calves) 2x/week.
• Maintain mobility: improve ankle dorsiflexion and hip extension; Stretching is measured and close to sport.
• Vary shoes/surface: Check for wear, choose the right model depending on your running style, avoid hard, sloping surfaces.
• Take regeneration seriously: sleep, nutrition, stress management – ​​the cornerstones of tissue healing.

When should you seek medical advice?

• Sudden, stabbing pain with loss of function or audible cracking.
• Marked joint effusion, feeling of blockage or instability.
• Fever, redness, severe overheating or a general feeling of illness.
• No improvement despite adjusted stress and exercises over 6-8 weeks.
• Suspected partial tear or complex accompanying injury.

Early assessment helps to initiate the appropriate therapy and to keep training breaks as short as possible.

Course and prognosis – realistic and individual

Healing from tendon irritations takes time. With consistent, adapted stress and structured training, resilience usually improves within weeks to a few months. The course is individual and depends on the severity, training goals, previous stress and everyday factors. A guarantee or a fixed time is not possible. What is crucial is the combination of patience, targeted exercise therapy and improvement in technique.

Practical self-help: A possible 4-step program

The program is an orientation. Individual adjustments to pain, sport and everyday life are important - we would be happy to advise you personally.

Special features of squats and jump training

• Adjust depth and speed: slower down phase reduces load peaks; Choose a pain-adapted depth.
• Stance width and foot position vary: Slightly wide stance can reduce front knee loads.
• Spanish Squat: Relieves the strain on the patellar tendon while simultaneously activating the quadriceps.
• Landing technique: actively use your hips, land quietly, keep your knee in line with your second toe.
• Dose volume: gradually increase the number of jumps and eccentric peaks, plan recovery days.

What we can do for you in Hamburg

In our orthopedic practice at Dorotheenstrasse 48, 22301 Hamburg, we combine a careful clinical examination with individual training advice. We create a structured, everyday therapy plan and support your return to sport - from pain management to technology optimization. We only use regenerative procedures such as shock waves or PRP after clear indications and information.