Identifying symmetry in running gait using a single inertial sensor

Area of Science:

• Biomechanics
• Sports Science
• Wearable Technology

Background:

• Running gait is sensitive to changes in intensity.
• Accurate measurement of center of mass (COM) vertical acceleration is crucial for understanding running dynamics.
• Existing methods may be complex or costly.

Purpose of the Study:

• To validate a novel technique using a single sacral inertial sensor for measuring COM vertical acceleration.
• To assess the influence of running intensity on COM vertical acceleration and its symmetry.
• To quantify gait symmetry using COM vertical acceleration.

Main Methods:

• Ten athletes completed 5-minute running trials at self-selected pace, plus 1km/h above and below.
• COM vertical acceleration was measured using a sacral-mounted inertial sensor and compared to a six-camera infrared system.
• Validity was assessed via correlation, typical error of estimate, and mean bias.

Main Results:

• The inertial sensor demonstrated high validity against the criterion measure (r=0.96, TE=1.84, MB=0.02).
• COM vertical acceleration was greatest at the slowest pace and decreased with increasing speed.
• Sixty percent of athletes showed asymmetry in COM vertical acceleration at one or more paces; 30% were asymmetrical across all paces.

Conclusions:

• A single inertial sensor is a valid tool for measuring COM vertical acceleration during running.
• This technique effectively detects alterations in COM vertical acceleration related to running velocity.
• The inertial sensor can quantify running gait symmetry using COM vertical acceleration.