An introduction to mobile running gait analysis
When most runners hear the term gait analysis they think of the same visual picture. Running on a treadmill in a lab or a clinic whilst being watched and possibly videoed by a professional. And for the most part this describes the vast majority of gait assessments that are performed all over the world every week. But this approach is known to be highly subjective and un-scientific and only evaluates the runner in controlled conditions, running on a machine in an unfamiliar and sterile environment.
Meanwhile in the background over the past 5 years significant advances have been made in the field of wearable technology and some of these advances have direct application to running data collection. Wearable devices have become smaller and lighter, battery life has improved, onboard memory has enabled enhanced local data storage, the range of metrics has increased and the accuracy and reliability of firmware algorithms has improved. This has all meant that wearable technology has now established itself as a credible method for measuring key parameters related to a runner’s gait.
Recent continued development of a small number of robust technologies has opened the door to a new approach to performing gait analysis. This approach is based around the concept of fitting wearable sensors to a runner during a typical outdoor workout and measuring various aspects of their gait. Even more than this, it can be used to collect extended duration data from multiple workouts over a period of days or weeks. Thus allowing a skilled specialist to form a complete profile of the runner's gait in different shoes, on different terrains and courses and at different speeds. And in all the cases that we have seen at Runfisx, the runners have forgotten very early in the workout that they are even wearing sensors and collecting data.
Fitting wearable sensors to a runner during a typical outdoor workout
Because running injury prediction and prevention is a very complex and multi-factorial subject, simply assessing one area or factor is not enough. With outdoor gait analysis and wearable technology some of the factors that cannot be addressed in conventional gait analysis can now be monitored. Factors such as terrain and course selection and workout frequency and training load. But most important of all is the nature of the data collection with wearable sensors. Firstly the sensors are measuring accurate and reliable values in an entirely objective way without human biasing. And secondly the sensors are mounted on the runner and hence are a measure of what the runner themselves is actually exposed to and not an indirect measure from a camera or gauge on the ground.
Collecting objective and repeatable data without the issue of human bias
So it is clear then that wearable gait analysis can move assessment methods much closer to the gold standard of what a purist specialist would need to ensure a truly valuable and realistic evaluation. However it is not just as simple as attaching one or two devices to a runner and then actioning the absolute results. There are some caveats to bare in mind. And they are related to the fact that any collected data requires due body coverage and correct data context. In a future follow-up article we will explain the workflow that we have refined in order to ensure that coverage and context are accounted for as well as how the same wearable technology can be used to improve treadmill assessments and how this data can be integrated with slow motion video capture and manual competency testing methods.
Here is a list of the main advantages that we’ve seen continually reinforced when applying wearable technology to running gait analysis:
The analysis can integrate with real workouts in real world conditionsThe sensors measure what the runner’s body actually feelsThe measured data is truly objective and free from human biasRepeat assessments can be compared more reliably Assessments can easily incorporate shoe, terrain and speed comparisons
In future articles we'll dig deeper into the specifics involved in an analysis, starting with the concept of bilateral measurement and asymmetry calculation. If there are specific topics that you would like to see addressed in our articles, just add a comment below.