Did you notice the way that Fabio Aru was standing as he got off his bike and waited for one of his many bike replacements on Stage 12 of this years Tour de France? He adopted that all too common 'duck's arse' posture where he was so locked up around the lumbar spine and hip flexors that he was 'fixed' in lordosis.
Speed forward to just over a kilometre from the finish on the same shortened Mt. Ventoux stage (due to high winds) and Froome ends up riding into the back of a stationary moto with Richie Porte and Bauke Mollema. His bike was so severely damaged he couldn't run with it. He ditched 'said' bike and starts running towards the finish.
Putting this into context Froome had just put in a huge effort up that climb, mostly seated and had dropped most of the other GC contenders. 99% of all riders getting off their bike after that would be incredibly loaded and stiff in their lumbar spine. Not Froome however. He was bolt upright and his lower back was nice and flat. There was a little too much lateral trunk instability for my liking, but in this instance he's well and truly forgiven. No 'duck's arse', more a running technique associated with a seasoned runner.
So what can we possibly assume from this, and how does it make him clearly a very efficient bike rider? I'm not going to use this blog to go into the minutiae of the complete pedal stroke and how that relates to efficiency in endurance riding (that will come in a further blog post soon), but what I have seen over the years is that there is a very high correlation between upstroke movement patterns/kinematics and efficient riding and I'm going to take that today.
Lombard's Paradox has been a fiercely debated subject within the cycling mechanics community for many, many years, and once you get your head around it, it's truly fascinating. It describes the paradoxical muscle contraction (when considered wrt cycling) between the hamstrings and quadriceps during the pedal stroke. The quads/hamstrings, like biceps/triceps are what's called antagonists - they work in opposition to each other, so when one is on the other is off. Do a bicep curl and hold the hand still. The bicep will be on, and the tricep will be off.
In cycling however, particularly when transitioning from peak power (3 o'clock on the crank) to half way up the upstroke, both the quads and hamstrings play the lead role in force development - at the same time. The rationale behind this is to do with moment arm length (torque production) the muscles are exerting on a particular joint. The higher the moment arm, the more the torque it can generate, and this dynamic changes depending on where within the pedal stroke we're discussing.
It breaks down as follows:
3 - 6 o'clock (downstroke): quads acting on knee extension, hamstrings acting on hip extension
6 - 9 o'clock (upstroke): quads acting on hip flexion, hamstrings acting on knee flexion
There are a few inhibitors to this relationship however, which get in the way of this very finely balanced Paradox, as there are other muscles that can do the same job (1.) Hamstrings that have poor eccentric-to-concentric abilities, dominant gastrocnemius vs soleus, and most notably, overactive hip flexors (psoas in particular). Oh, and a cadence that lowers in a fatigued state.
So I pose this scenario, wholly based on supposition, but it's a real-world scenario I see in 85% of cyclists riding with back pain. Hamstrings have poor concentric 'recoil' on the upstroke due to low cadence/poor muscle balance training. Gastrocs (as a two-joint muscle) compensate as a knee flexor by locking the ankle and the hip flexors as a hip flexor on the upstroke to assist the quads. Since Psoas attaches to the lumbar spine, here is the source of your back pain and 'duck's arse' posture (coupled directly with poor lower abdominal/core strength - but this is another blog).
Froome: high leg turnover thereby enabling good hamstring recoil, reducing the need of the hip flexors to compensate, allowing him to get upright and go full gas running up a hill in cycling shoes....
So what's the take home from all this, and most importantly, does it apply to you, a non-TdF rider?
1. Via reciprocal inhibition, start unloading the hip flexors but doing truck loads of accurate glute max and hip disassociation training. Think Bridging, Hip Extensions and ACCURATE Squatting.
2. Start building awareness of Eccentric Hamstring control. Think Eccentric Swiss Ball Curls and Nordic Drops.
3. Soleus - as discussed earlier try and avoid locking the ankle joint on the upstroke. Build awareness and strength in Soleus to allow Gastrocs to do less.
4. Cadence - too low and the hamstring concentric 'recoil' wont work.
5. DON'T THINK ABOUT PULLING UP, LET THE HAMSTRING 'RECOIL'/RESPOND
6. And yes, it certainly applies to you. Aside from the fact that TdF riders tend to be in more aero positions on the bike (thereby affecting pelvic tilt), it's still the same bike. And I'm seeing less aggressive front ends on the pro's now, so that's an interesting shift. #ItsAllAboutTheGlutes
1.: it is for this exact reason that I see a significant number of cyclists who are riding with pain and blame their bike for the issues. In a lot of cases their dynamic angles are fine, it's the way they're recruiting that is causing the pain. #ItsNotAllAboutTheBikeFit