Nicolás Palomares Olivares, Enrique Medina Ripoll, Bruno Bazuelo Ruiz, Christian Conca de la Asunción, Juan Carlos González García, Sergio A. Puigcerver Palau, Joaquín Villodre Jiménez, Sara Gil Mora
Instituto de Biomecánica de Valencia
The Instituto de Biomecánica de Valencia (IBV) and KELME have developed a prototype running shoe with a built-in electronic device which enables runners to better plan their training and prevent possible injuries during sports activities. The RUNSAFER system offers real-time information on the runner's biomechanical and physiological parameters. Information on the runner’s running pattern is transmitted wirelessly to their mobile phone while training. A cellular phone app informs the runner in real-time of their planned training session and objectives achieved, suggesting modifications to the activity to alter the biomechanical pattern and thus prevent injury. After each session, the runner can download all the information recorded from a website. Through this site, they can generate training plans, recommendations and monitor improvements made to the training session itself.
INTRODUCTION
The world of runningis currently experiencing a boom. There are currently more than 80 million runners in Europe, accounting for approximately 36% of the European population between 15 and 65 years of age. In recent years running has become one of the most popular sports, and with a growing number of enthusiasts.
Nonetheless, the sport is associated with injuries which force runners to interrupt their activity and lose the level of fitness attained until recovery or, even, in some cases, to abandon the activity all together. 38% of recreational runners are currently suffering or have suffered from running-related injuries and between 37% and 56% have been injured at least once during the last year. The majority of running-related injuries affect the knees, ankles or feet.
Injuries may be due to a number of different factors, such as possible training errors, unsuitable running technique, the use of unsuitable footwear, the type of surface run on, or not warming-up sufficiently. The majority of these causes of injury can be worked out by analyzing changes in the runner's biomechanical and physiological parameters while running.
The aim of the RUNSAFER project is to develop running shoes with a built-in electronic device which records and analyses the main biomechanical and physiological parameters in real-time, providing runners with information on possible injury risks.
SOLUTION PROPOSED IN THE RUNSAFER PROJECT
The RUNSAFER system (Figure 1) comprises a running shoe fitted with a micro-electronic measuring system capable of recording biomechanical parameters which characterize the runner's technique. The system is also capable of recording physiological parameters, supplied by a heart rate monitor. This information is transmitted wirelessly in real-time to the runner's cellular phone for analysis.
Figure 1:RUNSAFER system.
While running, both biomechanical and physiological parameters are modified, which means that the running technique is also affected. When the RUNSAFER system detects that the user's running pattern has been excessively modified, reaching a state of peripheral fatigue and leading to a possible injury risk, the user is notified via the cellular phone app, which offers a series of recommendations, such as reducing speed or terminating the training session.
The cellular phone app also provides all the additional information which is supplied by other commercial devices often used by runners, such as speed, exercise time, distance covered, GPS monitoring, calories consumed, running speed and heart rate.
At the same time, the athlete may also download all the information generated from a website, which has a specialist app for planning training sessions. This online application offers different training plans, depending on the runner's level. Based on the biomechanical analysis of the running action, the application offers recommendations for adjusting the training plan, with the aim of improving the runner's performance and preventing injuries. This website also includes features which are characteristic of online social networks, enabling the user to keep in touch with runners all over the world and to share other content, such as running routes and information on the most suitable footwear.
The following partners have participated in the project: Instituto de Biomecánica de Valencia (IBV), New Millenium Sports SL (KELME), Nuromedia GmbH, Dukosi Ltd, Fraunhofer-IPMS and Eesti Innovatsiooni Instituut (EII).
METHODOLOGY USED IN THE PROJECT
The Instituto de Biomecánica de Valencia (IBV) coordinated the project, while also participating in the following phases:
Definition of specifications to be met by the RUNSAFER system
Firstly, with the aim of identifying which biomechanical parameters measured on the runner's lower limbs could be related to the athlete’s degree of fatigue, a number of biomechanical evaluations were performed on a representative sample of runners. Based on these results, they decided which sensors the electronic devices should be fitted with to properly characterize the runner's biomechanical pattern.
Training plans were also generated in this phase in line with the runner's profile. These training plans, which have since been launched on the RUNSAFER system website, include a correction and adjustment system based on the evolution of the runners themselves and on the measurements obtained while running.
Lastly, other features which the RUNSAFER system required to meet runners' needs and expectations were defined, including content for the website and the cellular phone app, as well as usability requirements. In order to make a product which would be in line with runners’ desires, the opinions of users gathered in discussion groups and questionnaires completed by over 300 participants were taken into account.
Integration of the electronic device into the running shoe
Once the measuring system had been developed, in accordance with the initial specifications, the IBV and KELME integrated the electronic device into the mid-sole of the running shoe (Figure 2). This was carried out in such a way that the functional properties of the running shoe were maintained and the comfort for the runner was not affected.
Figure 2:Electronic device built into the KELME running shoe.
Assessment of the RUNSAFER system
Lastly, the IBV performed a series of tests with runners to assess the training plans defined, as well as to develop the algorithms implemented in the cellular phone app. These algorithms are capable of predicting the runner's risk of injury based on the biomechanical and physiological parameters measured. A total of 60 runners from different EU countries participated in this assessment phase.
Before commencing with the system assessment tests, a stress test was performed to ascertain the physical fitness levels of each runner and detect any possible heart problems. A constant velocity test was then performed to determine the evolution of the biomechanical and physiological parameters with the RUNSAFER system, starting from a state of rest and reaching a state of muscular fatigue (Figure 3).
Figure 3: Test at constant speed.
CONCLUSIONS
The RUNSAFER project has led to the development of a running shoe fitted with instruments for recording the runner's main biomechanical parameters. The main innovative feature of the RUNSAFER system, as opposed to other systems, is that it is the first device which characterizes running technique based on biomechanical parameters and which, along with information from the heart rate monitor, detects fatigue and provides the user with recommendations in real-time to prevent injuries and improve performance.
Consequently, this system could help millions of European runners to reduce running-related injuries, making the sport safer and more attractive.
Further information is available on the project's website: www.runsafer.eu
ACKNOWLEDGMENTS
The RUNSAFER project was funded by the Seventh European Framework Program (FP7/2007-2013) under number 285800.
