A thread on knee injuries in females and strategies to help minimize their potential
Weakness of the hip abductor & external rotator (ER) muscles is surprisingly common in otherwise normal & healthy females (Malinzak et al, 2001; Robinson, 2007).
That is just one piece of the..
overall puzzle.
Females tend to have a higher Q-Angle due to wider hips. The research is murky whether or not higher Q-Angle leads to more injuries, but honestly I’m not concerned about that as much as the biomechanical relevance of a higher angle.
When hips are wider, the sacrum is in a relatively higher amount of counter-nutation and the pelvic bones follow it into:
- External rotation
- Abduction
- Flexion
You can see how this could cause the deep hip external rotator (ER) muscles to become “shorter” or more “tight”, like the piriformis, glutes, and obturators.
Maclntyre et al, 2008 compared patellar mechanics between knees with no pain and with pain. They found the painful group had a statistically greater lateral shift of the patella, which happens often when Q-Angle is higher.
So if many females have a bias towards ER, why do they have weak ER muscles?
In my opinion it’s because muscles need to stretch to contract effectively. Just because muscle is “tight” does not at all mean it is strong.
What I often see is females
lacking strength in those muscles because they can’t effectively recruit them due to a lack of internal rotation (IR) capabilities of the pelvis and femurs.
There are a TON of theories why they are more predisposed ACL tears, but one aspect of it is related to a lack of hip IR.
If the pelvis and femurs can’t find IR, the femur has a tendency to collapse inwards in an attempt to “find” that IR. Since the lower leg is biased towards ER, the tibia typically likes to stay in ER.
Femoral IR + Tibial ER = Knee valgus.
If there is concurrent femoral IR + Tibial IR + good pronation at the foot, this is normal and knees slightly coming inwards isn’t necessarily bad.
So a key to helping females stabilize knees would be to improve their IR. I have a thread on that here:
Other things that help reduce knee injury potential are:
- Increasing relative max strength
- Emphasizing training in three planes of motion
- Plyometrics programmed appropriately
- Adequate nutrition and sleep
• • •
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If you want to:
- Be agile
- Be fast
- Get through the sticking point of a squat
- Deadlift
You want to have adequate hip internal rotation (IR).
However, in my experience it is often missing to some degree in many people.
The hip musculature responsible for hip IR are primarily:
- Adductors
- Inner Hamstrings
- Anterior fibers of the Gluteus Medius
- Tensor Fasciae Latae
In human movement, IR is necessary for mid-stance when we have our bodyweight on one leg and we need to propel it to the next leg. In cutting, we obviously need hip internal rotation to drive out of it effectively in a propulsive manner.
Many people are generally aware that the Serratus Anterior (SA) is an important player in shoulder health, but are unsure how to train it.
It has two main functions: Shoulder protraction & assisting in elevation of the arm...
The SA is actually a massively important player in overhead mobility.
It needs to hold and “pull” the scapula (shoulder blade) on the ribcage, or else the scapula would be very unstable & overhead mobility is limited.
When it can’t do it’s job (usually other factors at play here too), the scapula will be “lost” on the ribcage and won’t have adequate congruency on it.
We see this all the time with “winged out” scapulas.
A thread on the biomechanics of the Front Rack position and how to improve your mobility for it
The Front Rack position can be really challenging for some people because it requires maintaining around 90 degrees of shoulder flexion under load (Levangie, 2010).
To improve the..
mechanics of this position, let’s understand what’s happening:
Beyond around 60 degrees of shoulder flexion, the scapular external rotator muscles need to work harder to get the arm overhead due to the progressive upward rotation of the scapula (Neumann, 2016).
This means that the Serratus Anterior, Upper and Lower Traps all need to work together to accomplish this.
The Rhomboids, Lats and Pecs need to let go and relax.
This is often the part that is challenging for people.
A thread on how mechanics in the foot drives action at the hips
The body is made to interact & react with the ground.
Extension at the knee and hip is cued in the lower body when the foot arch falls/pronates & the supinator muscles are stretched (Neumann, 2010).
As Gary Ward says, joints act & muscles react. A stretch on a muscle will trigger it to contract.
The stretch places elastic recoil on the supinator muscles which then spring the foot back into supination upon toe-off in running and gait.
This also allows for a nice reaction
up the chain that causes extension at the knee and hip.
However, if the foot is excessively pronated, the supinator muscles are constantly placed on a “stretched” position. This limits them from being able to sense the stretch needed to then spring the foot into supination.