By Burke Selbst, PT, Owner of Focus Physical Therapy
Today we’re all about hips. This often overlooked joint may have a significant influence on your bike fit and riding comfort.
Let’s break down the biomechanics of hip joint alignment and address the more common cycling compensations I see in road and gravel cyclists related to hip joint alignment and mobility.
On your last group ride, whether that’s a weekend morning coffeeneuring run or a Mckenzie Pass out and back, have you noticed riders with a distinct knee bob to the outside at the top of their pedal stroke? When runners do this with their arms we call this a flyaway arm, so for this article I’m calling it the “flyaway femur”. This is a common compensation and although cycling is a fantastically low impact sport, this pattern can lead to a few of the more typical complaints I treat among cyclists including lateral knee pain, anterior hip/groin pain and low back and pelvis strain.
Here are the four most common causes of this compensation and how to fix them.
The hip joint is a deep ball and socket, and it’s oriented outwards, slightly forward and slightly up but this varies significantly between genders. Males have a socket that is oriented more laterally than women. This is important because at the top of the joint, when the femur is maximally flexed, the average male’s knee will be further to the outside than the average female’s (See Picture).
You can test this yourself.
Lay on your back with both legs straight and something under your low back to preserve your lumbar lordosis (the arch there) and to keep your pelvis from rocking backwards. Bring one leg up in a straight line as if you were pedaling as far as you can. Notice when your leg needs to move to the outside in order to keep coming towards your chest. If you did this well without compensating in your pelvis and low back, this test shows you a relatively ‘pure’ range of hip flexion.
Stand about 4-5 feet away from a wall and lean into the wall with your hands while keeping your body straight (this position begins to mimic the slight forward tilt of your pelvis on a bike saddle). Raise one knee actively while keeping your body straight with core tension. Raise your knee straight up as if you were cycling. Notice the height of the stopping point, and what happens if you allow your knee to move to the outside. Can you raise it higher? This test shows you a more ‘functional’ cycling applicable range of motion.
Now, take the previous test and repeat it with your hands planted on either a table/desk (a higher “endurance” style geometry) or a chair seat (a more aggressive geo). Notice the relative change in how high your knee goes in each position.
Chasing down the culprits
As we’ve seen above, this compensation is about the pelvis and femur and how they work together. Anything that causes the pelvis to tilt too far forward or the femur to come too high will lead to compensations based purely on joint anatomy.
Don’t Miss These Important Causes:
Reach is too far
This could be caused by a too-long stem, too much seat setback or both, which leads to too much anterior pelvic tilt and a lower (ie more aggressive) trunk angle.
To fix this, we typically start at the feet and work upwards and forwards. Make sure you are rock steady on your saddle at your preferred trunk angle, then adjust in your reach to meet where your hands can naturally ‘hover’ with minimal effort. In our bike fitting world we use sizing stems to help dial this in.
Bars are too low
Your reach may be good but if you slam that stem or are trying to make a short steering tube work, your bars may be just too low, forcing you again into a lower more aggressive trunk angle.
Fix this with a stem that has some rise and make sure you’re on a bike with a frame size and design that’s appropriate for you.
Seat is too setback
Without changing the front end of your bike (handlebar reach and drop), adding more seat setback will lower your trunk angle (more aggressive, more hip joint crowding) and less seat setback will open up your hip joints. This is a measurement that has a number of ‘right’ solutions and is interactive with not just your anatomy but also the style of bike and the type of rider you are. Your saddle choice and alignment will also be a factor here.
Although many bike manufacturers spec their bikes with the seatpost and saddle combos they think will work for most riders, everyone is different. Start with a very neutral mid-saddle rail position on the seatpost your bike came with and with your saddle set comfortably for you (more on this in another blog), begin to micro-adjust forward or backward to find your sweet spot. Need help? schedule yourself a fit with our team and we can help you dial it in.
Saddle is too low or cranks are too long or both
Our previous examples all dealt with how bike fit influences your pelvis on top of your femur. This problem is simply about how high your femur comes at the top of your stroke.
Fix this by ensuring you are on the right length cranks (find a very interesting article on this here: https://ridefar.info/2017/02/crank-length-and-comfort-for-long-distance-cyclists/), and that your saddle is at the proper height.
Off The Bike Solutions?
So far everything we’ve explored has involved an on-the-bike solution. There’s a good reason for this. With the hip maximally flexed and the knee bent, there’s very little muscle tension preventing the hip joint from travelling through its full range. There’s no muscle stretch that will change the end point of hip joint travel. There are however many general things cyclists can and should be doing off the bike to get more out of their riding. This includes in general hip flexor and quadraceps stretching, hip joint self mobilizations, hip, pelvis and core strength training and muscle balancing and neuromuscular reeducation techniques for hip, pelvis and low back proprioception and movement awareness.
For hip soreness and stiffness after riding, a good recovery program will include hip joint circles, supine bent knee fallouts, bridge variations and hip joint circles laying down, kneeling and standing.
Interested in developing your own recovery program and plan? Talk to our team.
Wrapping things up
A good bike fit performed by a physical therapist strikes a perfect balance between ergonomics and performance. In today’s article we looked at a number of ways body positioning and bike fit can lead to hip joint based compensations. If you or someone you know is experiencing stiffness or pain from riding and needs help getting your bike dialed in for your body and riding goals, reach out to our team. We look forward to helping you with your cycling goals and to make sure you are cycling comfortably for years to come!
Burke Selbst PT