Clinical Pilates in Practice: Biomechanics of Functional Tasks
This small study of healthy volunteers explored differences in the coronal biomechanics of the trunk, pelvis, hip, and knee joints, as well as gluteus medius muscle activity during walking and step down tasks.
Komsak Sinsurin, Raul Valldecabres & Jim Richards (2020) An exploration of the differences in hip strength, gluteus medius activity, and trunk, pelvis, and lower-limb biomechanics during different functional tasks, International Biomechanics, 7:1, 35-43, DOI: 10.1080/23335432.2020.1728381
Key Points: Biomechanics of Functional Tasks
Functional impairment of glute med can lead to excessive lateral trunk bending, which is often observed in people with knee problems.
During gait, the following was observed:
→ Increased contralateral pelvic drop and pelvic obliquity excursion, compared to step-down tasks.
→ Increased lateral bending versus step-down tasks.
→ Significantly greater knee adduction, compared to step-down tasks.
→ Peak hip adduction moments were greater than in step-down tasks.
Greater glute med activity was recorded during step-down tasks, compared with level walking.
Greater stability and balance are required for step-down tasks, than for gait, which is why less lateral trunk bending and pelvic obliquity should be observed in healthy adults.
Loading on the medial knee increases with step-down tasks, and increases as the height of the step increases.
Glute med activity is greater in the first 50% of stance phase in gait, and greater in the second 50% stance phase during step-down tasks.
The hip has greater control in the frontal plane than the knee joint.
A value of 1.4 Nm/kg is posited as a threshold to determine hip abductor weakness that requires rehabilitation.
Clinical Pilates in practice
Functional increases in glute med strength need to be trained in a variety of activities, rather than static single leg loading.
Because of the increased task demands during step-down for glute med strength, adding these exercises in early will likely lead to carry-over into gait.
→ Step Ups and Step Downs on the Wunda Chair.
Work on hip/knee adduction/abduction through flexion/extension in alternative positions.
→ Sleeper on the Reformer.
→ Bend/Stretch with feet in straps (Reformer) or leg springs (Cadillac).
Using alternative spring load positions on the Trapeze Table can challenge adduction/abduction during hip/knee flexion exercises.
Trunk lateral bending is also influenced by oblique strength, so increasing oblique strength will decrease the load requirements on the glute med, and can thus decrease load on the medial knee.
→ Side Leg Kick.
→ Side Lift.