Study Guide - Week 1
Foundational Principles
Name:
1. How does the diaphragm function in respiration (inhalation and exhalation)?
Exhalation – diaphragm ascends, eccentric action
Inhalation – diaphragm descend, concentric action
2. Why is every muscle considered tri-planar?
Every muscle is helical in nature and helical structures (fibers & bundles of fibers)
contract via rotation.
3. How does inhalation and exhalation affect the Sacrum and Pelvic Innominate
bones?
Inhalation – Counternutation (tipping backwards/extension), pelvic bones going into
external rotation and abduction – top of the pelvis opening/bottom closing
Exhalation – Nutation (tipping forward/flexion), pelvic bones going in internal
rotation and adduction – top of the pelvis closing/bottom opening
4. Why might a barbell front squat feel better for someone’s low back compared to a
barbell back squat?
Barbell Front Squat is going to allow to get their ribcage backwards in space and
start in more of flexed – so we’ll be in more counternutation and external rotation
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and abduction at the pelvis, at the foot we will have more plantarflexion and
supination. This will create a less extend/less arched low back
5. Why would someone’s knees want to cave in during the sticking point of a squat
around 90 degrees of hip flexion?
They’re unable to access nutation at the pelvis (nutation of sacrum and internal
rotation and adduction of the pelvic bones) so they are creating an orientation to
make up for it.
6. Why would the neck want to engage/be overactive during someone’s inhalation on a
corrective exercise?
They are using muscles of the neck like SCM, scalenes, upper traps are assisting us
in getting air in and have an ability to get enough expansion of the ribcage. It can
also be because some are in a sympathetic state which will increase the rate of
respiration and kick in secondary muscles.
7. What is the difference between pelvic relative motion and pelvic orientation?
Orientation is the whole structure moving as unit – this can be seen all throughout
the body – anterior orientation – the pelvis dumping excessively forward or rolling
through the ankle at the foot to supinate or pronate.
Relative Motion is bones or segments rotating on one another in the same direction
at different speeds/magnitudes – the pelvis nutating as the lower limb internal
rotates, and the foot pronates.
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