Week 7 - Mechanics, analysis & training of standing up Flashcards
Kinematics of standing up from a chair
- Go from large BoS (thighs/feet) > smaller BoS (just feet)
- Inclining of trunk fwd. + ext. of hip/knee during standing w/ DF @ ankle.
- Thighs off at 30% movement duration
- Knees move forward slightly/sh’ moves fwd, upw
At thighs off, force thru feet is:
150% BW to propel the body upwards to stand
Muscle activity when standing up from a chair:
(1) Tib ant.: translates knee fwd during DF
(2) Quads (hip/knee extensors): Extend up, active just before thighs turn off
(3) Gastroc/soleus: break the prog. fwd. + pull you back to upright.
Pre-extension phase of standing up from chair:
- Feet placed back so that ankles are behind knees (knee flx. / ankle DF)
- Inclination of trunk fwd. by flexion @ hips w/ extended trunk
Extension phase of standing up from a chair:
- DF of ankle to bring knees fwd.
- Sequence of lower limb extensions @ knees/hips/ankles.
Adaptive behaviours in pre-extension phase of standing up:
- weight thru good side
- widens base of support
Adaptive behaviours in extension phase of standing up:
- Falls backwards
- Pushes thru arms
- Use good side
- Final alignment flexed
Describe BoS, + movements @ hip, knee, & ankle during standing up in sagittal plane (starting position)
Hips: flexed
Knees: flexed
Ankles: plantargrade w/ slight DF
BoS: Butt, thighs, feet
Describe BoS, + movements @ hip, knee, + ankle during standing up in sagittal plane (pre-extension = pre-thighs off)
Hips: >90 flx.
Knees: slight flexion
Ankle: DF
BoS: butt, thighs, feet
Describe BoS, + movements @ hip, knee, + ankle during standing up in sagittal plane (extension phase = after thighs off)
Hips: extending
Knees: extending
Ankle: start DF, throughout PF
BoS: feet
Describe BoS, + movements @ hip, knee, + ankle during standing up in sagittal plane (finished position=standing)
Hips: extended
Knees: extended
Ankle: plantargrade
BoS: feet
