In October 2014 I attended the Retul ‘Cycling Specific Injury Management’ course in Manchester at the home of British Cycling. A fascinating two days with lecturers including Todd Carver (Chief Fit for Retul), Phil Burt (British Cycling Lead Physiotherapist), Dr Paul Barratt (British Cycling Biomechanist) and John Dennis (Retul Lead Physiotherapist). Theoretical and practical learning included biomechanics of cycling, functional movement assessment, common cycling injuries assessment, 2D and 3D cycling analysis using the ‘Retul Muve Fit Bike’, management for structural and functional abnormalities and identification of normal kinematic ranges for road, tri and mountain bikes. I also had the opportunity to have a tour of the British Cycling complex. Highlights of the tour included seeing Sir Bradley Wiggins training hard in the gym, seeing British Cyclists train on one of the World’s fastest board tracks and climbing to the top of the 8 metre start hill of the indoor BMX track.
As discussed in my previous blog in August 2014, knee pain is considered within the research as one of the most common overuse injury amongst cyclists. During the past few years of carrying out bike fits at Physiokinetic, knee pain has certainly been one of the leading reasons for people seeking a professional bike fit. I have therefore decided to write in greater depth about one particular knee injury I see on a regular basis prevalent in both runners and cyclists, patello-femoral pain syndrome (PFPS).
The knee joint is a hinge joint and located between two multi-axial joints, the hip and the ankle. It is well recognised that the knee is the most commonly injured joint in cyclists. It is possible this is due to the knee being unsupported as there is no contact with the bike. Large forces through long levers such as the femur generate large torque and the patella acts as a fulcrum through which the force produced from the gluteals and quadriceps is transferred to the tibia and ultimately to the pedal. The quadriceps tendon attaches the quadriceps to the patella and the patella tendon attaches the patella to the tibia. The joint under the patella is the patello-femoral joint (PFJ).
As the knee flexes and extends the patella glides between the groove created by the condyles at the distal end of the femur. The PFJ is typically a smooth surface with a friction co-efficient of nine times that of ice sliding over ice! There are therefore a variety of factors which can result in movement of the patella or ‘mal-tracking’ and ultimately result in pain. These include muscle length, control and strength. During the pedal cycle, the knee goes through approximately 80 degrees of motion. The knee begins the power phase flexed at about 110 degrees and extends to about 30 degrees of flexion. The quadriceps provides most of the force but there is also input from the hamstrings and gluteals. During a concentric contraction of the quadriceps there are increased compressive forces around the PFJ. These forces can be further increased by poor saddle or cleat positioning, cycling in high gears, hill climbing and a too slow cadence.
Patello-femoral pain syndrome refers to anterior knee pain emanating from the PFJ and the supporting soft tissues. It is related to a combination of factors involving mal-alignment of the knee extensor mechanism. PFPS is an early indication of cartilage softening that can progress to cartilaginous damage. Abnormal ‘tracking’ of the patella can result in uneven wear on the back of the patella associated with increased pain under the knee and a grating sensation. Quadriceps and patellar tendinopathies are often associated with PFPS. Patients generally report that anterior knee pain is worse when the knee is loaded e.g. during or following cycling, when squatting, when climbing or descending stairs or during prolonged sitting.
As well as manual therapy for the physiotherapy treatment of PFPS there is evidence for the importance of rehabilitation and ‘off the bike’ work for cyclists. Bike adjustments can be made but we can also tune our bodies to become more adaptable to aid cycling and joint biomechanics. There are several ideas behind stretching including the theory that it can cause a lengthening of muscles. Muscle length is essentially fixed as there are anatomical origin and insertion points. My interpretation is that increased flexibility encourages muscles to ranges of motion beyond that achieved when walking, sat at a desk or cycling. If left un-addressed the tightness can contribute to limitations of muscle function, muscle imbalance, joint stiffness and result in injuries such as PFPS.
Stretching, foam rolling, targeted yoga and sports massage are all part of a cyclist or runner’s toolkit to deal with muscle tightness and thus aid in preventing injury. The recommended time to stretch is following a ride. You are most likely to do a better job of this in front of the telly after taking a shower up to an hour after your ride rather a half hearted rushed stretch session as soon as you’ve jumped off your bike! For athletes involved in regular training foam rolling routinely has a positive effect on fascia- a network of connective tissue which in healthy tissue is flexible, relaxed and has the ability to stretch without resistance. Key areas for cyclists to foam roll include the quadriceps, ITB and gluteals. If you would like to see the benefits you can achieve from foam rolling for yourself University students can buy a foam roller from the Scholarships Office in the Munrow Sports Centre. We also have a stock for Physiokinetic patients to purchase at our City Centre clinic. The foam roller will tend to feel more effective on the quadriceps, ITB, calves and to some extent gluteals. Smaller areas of soft tissue tightness often respond well to direct pressure using rounder objects with a more focussed point of contact. An example of this would be using a lacrosse ball to ‘trigger point’ the gluteals.
In summary, despite the low impact nature of cycling, cyclists are not excluded from injury risk and musculoskeletal problems. Prolonged positions in combination with repetitive limb movement seem to be the main reasons for injury risk. In order to achieve the most efficient output when cycling whilst being comfortable and reducing the likelihood of injury, follow a few key steps;
1: Acquire optimal bike set up advice from a professional
2: Seek early physiotherapy treatment for injuries
3: Complete regular specific strength training
4: Learn to self manage your flexibility
And don't take my word for it….
‘I love seeing so many people out on bikes, but few things frustrate me more than seeing someone riding a machine that is poorly set up’ Sir Chris Hoy
Toni Keech is our Bike Specialist at Physiokinetic. If you have a cycling injury or would be interested in having a bike fit from the physiotherapy perspective (optimising the bike and the rider), please call Physiokinetic on 0121 440 7736 or email email@example.com for more details.
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