The FES Bike Race
The "Functional Electrical Stimulation (FES) Bike Race" of the Cybathlon 2020 is a race of tricycles propelled by the muscles of the paralysed legs of riders with a complete spinal cord injury.
The muscles are activated through the application of electrical impulses which trigger the contraction. Classically, an angular sensor placed in the pedal crankset triggers pre-programmed stimulation sequences to activate the quadriceps and hamstrings of both lower limbs. This is a technical-sports event where performance depends on technology and the capacity of the muscles to produce prolonged efforts.
2016 : First Cybathlon
The approach of the Camin team with its Freewheels project is to work on a pedalling platform and a training protocol that is accessible to the greatest number of people with a spinal cord injury (cost, implementation, autonomy of use).
In 2016, the team took part in the very first edition of the Cybathlon by equipping itself with a commercial tricycle and adapting it for use with a commercial electric stimulator. The team was new to FES cycling and set up a pedalling platform and training protocol with a first pilot, Jérôme, who also had a full paraplegia. The proposed solution was mainly based on the state of the art in the field. The event consisted of covering 750 metres in less than 8 minutes. Jérôme qualified for the finals and finished in 6th position.
Les recherches continuent
For the new competition, initially scheduled for May 2020, the event consists of covering 1200 metres in less than 8 minutes. The team has worked on a new training protocol by equipping Xavier, our new pilot, with an ergocycle allowing him to train at home 3 to 4 times a week according to a training plan established by the team. Xavier is paraplegic and a great sportsman (handbike, plane piloting, etc).
During this 7-month period, a precise monitoring of performance was carried out in order to gain knowledge and eventually be able to offer the same training approach to patients in the rehabilitation centres. Indeed, the final objective is to give as many people as possible access to this technology, which allows physical training to be carried out while practising a fun activity.
The pedalling platform has been completely revised by equipping it with new sensors: inertial control units and power sensors to allow more precise control of stimulation sequences and more complete performance measurements.
A software programme, IMUSEF, has been developed: it offers the possibility of triggering muscle activation based on angular measurements of the thighs according to a calibration carried out on the basis of the forces applied to the pedals.
A clinical research protocol validated by a Personal Protection Committee (CPP) and the ANSM (National Agency for Safety and Medicines and Health Products) has been set up for both studies (2016 and 2020).
La compétition, version 2020
The health situation has led the Cybathlon organisers to postpone the competition to November 13-14 in a remote version. As far as our discipline is concerned, the tricycles will be installed on instrumented "hometrainers" that will transmit the pedalling data live.
Xavier has continued to train at home during the confinement until now to take part in the competition. The team has maintained close contact with him throughout these months. As in 2016, scientific, technological and medical advances imply a great personal investment by the different team members in an adventure that is above all human.
Last July, after the confinement, Xavier was able to come to Montpellier to try out the tricycle indoors on a "hometrainer" as well as outdoors on a cycle track and a karting track. Thanks to his determination throughout this protocol, his training today allows him to pedal in conditions that bring him pleasure and relaxation which is the main result of our work. If the health situation allows it, Xavier will come to take part in the Cybathlon 2020 event next November in Perpignan, an experience of remote sharing between the different teams.
Testimony of Xavier, pilot of the experiment
The fact that my legs are the driving force in my physical activity is huge and unexpected for me. I did a lot of running before my accident and it was an activity that was very good for me. I loved to run and my mind would escape when I was running. After my accident I quickly saw my legs as useless, as dead weight, and often made my life difficult.
Participating in the Cybathlon, but especially the research work of the team and the opportunity it gave me, allowed me to rediscover forgotten sensations, sensations that I only had when I was running, and on top of that it is through my legs that I find them again today!
La préparation en images
En coulisses : que ce soit en salle, sur une voie cyclable ou sur un circuit de Karting, tous les environnements sont là pour améliorer la préparation à la compétition.
Crédits : © Inria / Photo H. Raguet