Marcos Duarte
Laboratory of Biomechanics and Motor Control (http://demotu.org/)
Federal University of ABC, Brazil
The measurement of spatial and temporal characteristics of a movement pattern is an important resource for the characterization of an observed movement. Such variables are typically the first description performed in gait analysis (Whittle, 2007) and also used in the study of other movements and biological systems. The determination of such variables is also an excellent and valuable example of the application of relatively simple concepts of kinematics.
Gait is the pattern of movement with the limbs by animals during terrestrial locomotion and for humans, gait consists of walking or running. Gait is typically a repetitive task where the overall pattern of movement repeats after a certain period or cycle. In the context of human gait, the movement of interest, walking or running, can be defined by steps or strides performed with the limbs. A step is the movement of one foot in front of the other and a stride is two consecutive steps with alternation of the limbs, as illustrated next.
The most commonly investigated spatial and temporal characteristics in the context of human gait (walking or running) analysis are:
Some of these variables can be normalized by a parameter to take into account individual characteristics or to simply make them dimensionless, for instance:
The article Bipedal animals, and their differences from humans by Alexander describes an interesting comparison of the spatial and temporal characteristics, as well as other biomechanical and physiological variables, of gaits by humans and other animals. Alexander found a lot of similarities across animals, particularly concerning the spatial and temporal characteristics, but at the same time he concludes that no animal walks or runs as we do.
With aging, typically it's observed a decrease in gait speed, an increase in double stance time, and an increase in step width, among other changes. See the website Gait Disorders in the Elderly for more details.
A study involving 26,802 individuals 60 years and older from 17 different countries found that the simple measurement of gait speed, combined with a kind of memory test, can be used to identify high-risk seniors that will develop dementia (Verghese et al., 2014).
from IPython.display import IFrame
IFrame('http://demotu.org/wp-content/uploads/2016/08/SampleReportWalking.pdf', width='100%', height=450)