Characteristics of a Force Portrait
We describe each force portrait by the following metrics.
- Vertical, Lateral, and Running Direction Magnitude.
- Volume
- Vertical and Running Direction Symmetry
By tracking these metrics and observing their changes over time, valuable insights into the nuances of your movement under different conditions can be obtained.
These metrics measure the peak force in each direction. Minimizing lateral forces and maximizing vertical forces are associated with enhanced running efficiency.
- Vertical Magnitude ( higher ~ better )
- Lateral Magnitude ( lower ~ better )
- Running Direction Magnitude
This is a measure of the overall size of your Force Portrait, taking into account peak forces in all directions. A smaller volume typically means you're running more efficiently.
We can separate the full gait cycle into left and right steps. Each magnitude is measured independently for each leg then compared. This gives us a symmetry score in each of the three directions.
Symmetry is critically important in running. Asymmetries may lead to injury over time, or may be useful indicators of progress when recovering from injury. Ideally a runner should be as close to 100% symmetrical as possible in each direction.
- Vertical Symmetry: This shows how balanced your forces are when moving up and down. A perfect score of 100% would mean that the forces on your left and right sides are evenly balanced. If you score lower, it may indicate that one side is absorbing more shock than the other.
- Running Direction Symmetry: This looks at how balanced your forces are when moving forward and backward. Ideally, your left and right sides should be evenly balanced, meaning your running is more efficient.
- In addition to a visual perspective, Force Portraits can be characterized using key quantitative values.
- Vertical Symmetry and Running Direction Symmetry are crucial parameters to focus on when analyzing Force Portraits. By scrutinizing these key parameters, valuable insights into your running form can be gained, enabling adjustments for improved performance.