Changes in Gait due to Ankle Plantar Flexor Muscle Fatigue
Advisor Information
Jenna Yentes
Location
Dr. C.C. and Mabel L. Criss Library
Presentation Type
Poster
Start Date
6-3-2015 9:00 AM
End Date
6-3-2015 10:30 AM
Abstract
In this case study, a protocol was created in attempt to examine gait characteristics before and after fatigue on the plantar flexor muscles. The lone participant was a healthy 25 year-old female. Kinematics were recorded using a 12 camera motion analysis system (MAC, Santa Rosa, CA) and kinetics were recorded using AMTI force plates (AMTI, Watertown, MA). Two separate conditions were completed within this test. The first condition established a baseline for walking and served as a control to compare within the experiment. The participant then completed a fatigue protocol, which consisted of standing calf raises on a wooden 2x4 for 90 seconds at approximately 0.8 Hz. Immediately following the fatigue protocol, the participant returned to the original starting point and the post-fatigue walking trial was completed. An approximately one to two degree increase in range of motion was discovered pre- to post- fatigue protocol in the ankle and hip, while a six degree decrease was seen in the knee. Pre-test ankle moments decreased 17%, while peak knee and hip moments increased 38% and 28% respectively. In the same way, peak power both produced and absorbed at the ankle decreased 7% and 6%, while knee (41%, 48%) and hip (17%, 140%) increased. Since peak propulsion power is reduced within the ankle plantar flexors due to fatigue or weakness, more power must be produced across the more proximal joints to compensate. This provides an example of how gait can change in order to generate similar powers when distal muscle weakness occurs.
Changes in Gait due to Ankle Plantar Flexor Muscle Fatigue
Dr. C.C. and Mabel L. Criss Library
In this case study, a protocol was created in attempt to examine gait characteristics before and after fatigue on the plantar flexor muscles. The lone participant was a healthy 25 year-old female. Kinematics were recorded using a 12 camera motion analysis system (MAC, Santa Rosa, CA) and kinetics were recorded using AMTI force plates (AMTI, Watertown, MA). Two separate conditions were completed within this test. The first condition established a baseline for walking and served as a control to compare within the experiment. The participant then completed a fatigue protocol, which consisted of standing calf raises on a wooden 2x4 for 90 seconds at approximately 0.8 Hz. Immediately following the fatigue protocol, the participant returned to the original starting point and the post-fatigue walking trial was completed. An approximately one to two degree increase in range of motion was discovered pre- to post- fatigue protocol in the ankle and hip, while a six degree decrease was seen in the knee. Pre-test ankle moments decreased 17%, while peak knee and hip moments increased 38% and 28% respectively. In the same way, peak power both produced and absorbed at the ankle decreased 7% and 6%, while knee (41%, 48%) and hip (17%, 140%) increased. Since peak propulsion power is reduced within the ankle plantar flexors due to fatigue or weakness, more power must be produced across the more proximal joints to compensate. This provides an example of how gait can change in order to generate similar powers when distal muscle weakness occurs.