Due to the repetitive nature of cycling and the long hours required to train we frequently see overuse injuries. As injuries develop, riders will often find advice to foam roll more, stretch nightly, or get a new bike fit. In an effort to clear the air on what, when, and why, we teamed up with local bike fitter extraordinaire, Ryan Ignatz at Colorado Multisport to help decide whether your body or your bike is the problem.
We will cover common injuries on the bike and how to best assess your bodies limitations at home as well as how to change bike position to fix it. In part 1 we are looking closely at lower back pain and front of knee pain.
Let's dive into a few common postures we see in riders that can contribute to low back pain. Looking from the side we can see there are three basic positions we can be in: 1. posterior tilt (tucking your butt under you), 2. anterior tilt(belly falls forward) 3. neutral (perfectly in between). What does your back look like on the bike?
Posterior chain stiffness, mainly hamstring or glute tightness, could lead to a posterior pelvic tilt position on the saddle (“tucked butt”) as is shown in the picture above on the left. This makes the spine flex more. This position leads to increased pressure on the lumbar discs and also increases the recruitment of your quadriceps muscles during the pedal stroke. An increase in quad use means more pressure on the front of your knee during each pedal stroke.
A common test we would use in the clinic to assess if your hamstrings are the limiting factor would be the 90/90 hamstring length test. If you fail the test because your muscles are too tight, improving hamstring length could allow the pelvis to rotate more forward improving the neutral spine position.
90/90 HS length test: The patient lies supine with the hips and knees flexed to 90º and grasps behind both of his or her thighs to stabilise the hip joints, then actively extends each knee in turn. Inability to extend the knee to within 20º of full knee extension implies hamstring muscle tightness.
If your pelvis is in a relatively anteriorly tilted position (belly falling forward) while riding, your Hamstring flexibility is probably adequate, but your hip flexor mobility is most likely limited pulling your pelvis anteriorly on the saddle. It is the iliopsoas muscle that has the strongest pull and compressive effect on our spine. It is attached to the L1-L5 and T12 vertebrae. A tight psoas can pull your spine forward at the bottom of your pedal stroke compressing the spine and the discs associated. A chronic state of hip flexor shortening can lead to an increased anterior pelvic tilt which is very harmful to the discs, especially the L5-S1.
Learn from expert bike fitter, Ryan Ignatz about how posture changes can fix lower back pain and anterior knee pain while cycling.
A common test we use in the clinic to assess hip flexor and quadriceps tightness is the Thomas Test. To perform this test at home: lay face up on a firm table with lower gluteal folds at the end of the table and hips and knees bent. (Patient may hold the legs in flexion with their hands). Keep one leg flexed and slowly lower the other leg letting it extend as far as it can. The test is positive for hip flexor tightness if the affected hip cannot fully rest on the table or remains slightly flexed (i.e. another person could slide their fingers under your leg). The test is positive for quad tightness if your foot wants to kick out and your knee is not resting at a 90 degree angle. Lastly, this test can be positive for lateral hip and quad tightness if your knee wants to move away from centerline as you lay face up. This could be an indication that soft tissue is pulling your knee away from center as you ride ( seen in the video below).
In the clinic, we tend to find that anterior pelvic tilt is less likely to be purely a mobility problem and tends to associate more with a movement coordination deficit. If you can't produce the stability from your core musculature to keep the spine stiff and rigid so you can produce power on the bike you will compensate by dropping into excessive lumbar lordosis. Due to the anatomy of the joints, mechanically your spine becomes more rigid due to your vertebrae locking which takes the place of a strong and coordinated core function. Basically, you are relying on your bones for core stability instead of muscles. You are most likely lacking core strength to provide stability and rigidity to the spine to produce power on your bike. Mechanically you have produced the stiffness needed to produce power. Commonly, clients who exhibit this posture on the bike for prolonged periods of time want to bend forward when getting off the bike to relieve pressure in their low back.
A good test for core stability is how long you can hold a plank for. Typically I like to see a client be able to hold a solid or correct plank for 60-90 seconds. If the drop between your handlebars and your saddle is high or a more aggressive position, you likely need more core stability.
If someone exhibits increased anterior pelvic tilt (belly falling forward) on the saddle we tend to see them drop into this position in the plank position. Your pelvis should be tucked slightly into a posterior pelvic tilt (belly button tucked towards the chest), actively engage your shoulder blades by pushing them away from midline, and think about pushing your head and heels apart.
Most people perform the plank incorrectly. Most people that exhibit increased lordosis on the bike drop right into that same positioning in the plank. This is why it is a really good idea to have an objective set of eyes on your plank to ensure proper form and a neutral spine. You probably don't have the core strength unless you have been working on core strength.
If you find that you have adequate mobility and strength but still experience low back pain, your bike position or posture on the bike needs to be assessed. As seen in the video above with Ryan, posture coaching can make a huge difference in addition to having your bike set up correctly.
If you are experiencing pain while riding, schedule an appointment with us or with Ryan at Colorado Multisport to have a full assessment performed.
Email us or call at 303-444-5105 to schedule.
Ryan can be reached at https://www.coloradomultisport.com/