Pronation is the inward rolling motion of the foot from when it makes initial contact with the ground and progresses to a full foot ground contact during a single step. The pronation motion occurs during the first half of each stance phase and is an essential part of how the body absorbs running impacts – so it’s not something runners should aim to eliminate. Different runners will go through different ranges of motion and we separate these into Neutral Pronation, Under Pronation, and Over Pronation categories in line with thresholds determined by previous research.
Over Pronation and Under Pronation
Over Pronation has typically been highlighted as an undesirable aspect of running technique, but both Over Pronation and Under Pronation have been linked to higher injury risk due to additional stresses placed on the soft tissues of the leg. Aiming for a Neutral Pronation is often recommended as a way of maintaining optimal biomechanics of the foot and ankle, aiding appropriate running technique and reducing the likelihood of running-related injuries.
If running pain-free, runners may be best advised not to change their pronation. However, to improve Under or Over Pronation, NURVV RUN provides the tools for runners to monitor whether their desired changes are working.
NURVV Run measures pronation for each left and right step taken during every run. The percentage of steps with neutral pronation is provided for each run in the Run Summary and is also tracked over longer periods of time as part of the Running Health app feature. A detailed breakdown of the distribution of pronation categories for the left and right foot are also available within Running Health - Pronation. Left and right pronation measures are also used to determine the Pronation Balance value in Running Health to evaluate the percentage bias towards a higher degree of pronation on the left or right foot.
Attempting to make any modifications to pronation levels should be made carefully, especially if there are no previous or current running injuries. However, if a runner is consistently having running-related issues (lower leg pain/discomfort), regardless of the distance ran or shoes worn, it might be useful to consider improving pronation, especially if their percentage of Neutral Pronation is low.
Approaches to modify pronation include foot mobility and ankle strengthening exercises, single-leg balance and stability exercises. It might be also useful to consider footwear selection. More information on these strategies is outlined in Running Health/Improving Pronation to Reduce Injury Risk.