The knee: A user’s guide

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HOW YOUR KNEE WORKS ON THE RUN

‘Your knee is a complex hinge joint,’ explains physiotherapist Paul Hobrough. It’s a synovial joint, which means it has a capsule filled with synovial fluid for lubrication. It has four key ligaments for protection against unwanted movement and meniscus cartilage for shock absorption, essential when you’re pounding the pavements.

‘When you’re running, the knee acts as a shock absorber as well as a key mechanical component of your whole gait cycle,’ says Hobrough. ‘Upon impact with the ground, the knee is able to flex to absorb your body’s weight. It then works with the foot, ankle and hip as a mechanical unit to propel you forward.’

Your knee couldn’t get far without its support network though. ‘The surrounding muscles play an essential role during the run for its control and support,’ says Hobrough. The main players are the quadriceps for knee extension, and the hamstrings for flexion. ‘Your gluteus medius and minimus muscles also have a large role to play, as does the ankle. They all strive to control unwanted movement and facilitate desirable movements.’ The iliotibial band (ITB) – the stabilising ligament that runs down the outside of your thigh from hip to shin – also plays a big part in control, driven by the gluteus maximus and your hip flexors. So the kinetic chain of the knee on the run involves much of your leg.

HOW TO KEEP IT IN WORKING ORDER

Knee injuries are depressingly common among runners. There are a number of factors at play, but according to Hobrough, recent research highlights that how far your knee travels inwards mid stance (when your body is over your foot) is a key issue. Essentially, the less control the surrounding muscles have over the knee, the greater your injury risk. And bad news for female runners: ‘A woman’s knee moves more medially [inwards] than a man’s,’ says Hobrough. Strengthening the surrounding muscles, then, is key to side-stepping injuries.

ITBS

What is it? Iliotobial band syndrome is pain felt on the outside of the knee, which stems from a tight or inflamed ITB.

Symptoms: Swelling and pain on the outside of the knee. To judge whether you’re suffering, perform this quick self-test: bend the knee to 45 degrees – any pain on the outside indicates an ITB issue.

Cause: As with many running ills, the main culprit is overuse. But tight hip flexors and quads, weak glutes, poor foot function, training when tired, training when under-fuelled, over-striding and an exaggerated heelstrike are all aggravating contributory factors, according to physiotherapist Noel Thatcher.

Beat it: ‘Stretch, invest in a sports massage and adjust your training volume to lighten the load,’ says Thatcher. Interestingly, speedwork is actually a good option when suffering with ITBS, as it is less painful due to the knee’s greater angle of flexion and less frequent loading. You should obviously seek expert advice if the symptoms don’t improve.

Prehab: The best policy is to avoid the trigger of overuse. ‘Build your training mileage up slowly and spread the load over multiple runs to give your body greater opportunity to recover,’ says Thatcher. Make sure you stretch your quads and hamstrings.

PFPS

What is it? Patellofemoral pain syndrome, aka runner’s knee’. An irritation caused by the stress of running, it localises where the patella rests on your thigh bone. Although, ‘pain may come from several structures around the knee’, says Thatcher.

Symptoms: Tenderness behind or around the patella. You may also feel pain towards the back of the knee, or a sense of cracking, or that the knee’s giving way. Steps, hills, and uneven terrain may aggravate the pain.

Cause: This results from poorly controlled movement of the knee due to poor pelvic stability, poor foot function, or both,’ says Thatcher. ‘And it’s most common in female runners.’

Beat it: Reduce pain with taping, soft tissue massage or foot orthotics; back off your mileage and cross train to maintain fitness,’ says Thatcher. ‘Then focus on strengthening your glutes and lower leg muscles.’

Prehab: ‘Gait analysis will help identify any problematic patterns which could lead to injury,’ says Thatcher. Strengthening the surrounding muscles is also essential and gradually increase your load on the exercises for best results. ‘The body will adapt to stress if it is applied in a progressive and controlled way,’ says Thatcher.

INJURY-PROOF YOUR KNEES

Strength and conditioning coach Gareth Cole has the following prehab prescription to safeguard your knees. Perform three sets of 15 repetitions of each exercise three times a week, increasing the tempo as you progress.

Forward lunge in stance

Why? Here the hip and knee have to work together to slow you down from the forward movement,’ says Cole. ‘This increases the load at the knee and hip, mimicking both the landing [stance] phase, and push-off [propulsion] phase of running.’

How: Stand in a stance phase, left foot forward. Now lunge forwards, pause, then slowly return to the start. Repeat.

Box drop

Why? You’re simulating the run here, recreating the mechanics of landing,’ explains Cole. ‘It produces a high but controlled force to the knee while your quads slowly lengthen eccentrically to control the tempo.’

How: Stand with one foot on a box at mid calf height. Slowly lower your non-standing leg to the floor, maintaining an upright body, then bounce back upwards. Complete the set, then switch legs.