3D Running Gait

To get started with MotionMetrix’s 3D Runnig Gait, you just need two depth sensing Kinect cameras and a computer. In less than a minute’s test at any speed 9-24 km/h on the treadmill, a complete 3D running analysis report is generated. No markers or tedious setup procedures, just running.

The report structure is very easy to understand even if you are not that experienced. All parameters are presented in relation to elite level performance or normative data from a group of over 50 000 runners to facilitate your assessment. The report is divided into three main categories, Running Performance, Gait Characteristics and Joint Loading.

A key parameter in the Running Performance page is MotionMetrix’s unique Running Economy (RE) value. It depends on the total mechanical work of the runner’s motion and also how efficiently the runner is able to store and release elastic energy in tendons and muscles (“elastic exchange”). Less work and more elastic exchange gives better RE. The stride parameters given in the Running Performance page all have impact on work and elastic exchange and they are evaluated in relation to long distance elite performance. The target is to minimize RE and a star rating guides you in the right direction.

Using cluster analysis on the big database of runners, we have found six fundamental runner profiles. We gave them names that match their characteristic style: Long Strider, Power Racer, Eco Sprinter, Quick Stepper, Constant Glider and Easy Strider. Some profiles are more efficient than others, some faster and some less prone to injuries. For each profile, we have collected informati0n about race performance, injury rates, primary injury sites, etc. Which category do you belong to?

 

The Gait Characteristics page gives detailed information about the runner’s kinematics in the sagittal and frontal planes. Large asymmetries or extreme parameter values are signs if abnormal gait which can increase the risk of  injuries. As always with MotionMetrix, all parameter data are put in context by relating to elite performance or the normal population.

 

More than 50% of all runners get injured each year and 50 % of the injuries involve the knee. While there may be many contributing factors to the development of an injury, it is ultimately the load applied to the lower limbs that is the trigger. No matter how experienced you are, there is no way to anticipate the loading level by visual inspection or video analysis. You need to calculate it and this is what we do in the Joint Loading page. The calculations are based on inverse dynamics which yield the net forces and moments acting on a joint. Focus is on the knee and hip joints. To assess if a joint loading variable may be harmful, it is compared with normative data from over 600 runners who have done the test. In addition, a built-in guide helps you to relate the joint loading variables to specific stride parameters. This allows you to make targeted stride corrections to reduce a specific force or moment from harmful level to normal. Once you have tried this approach to injury preventive work, you will never go back.