Functional Electrical Stimulation Bike Race
Pilots with complete Spinal Cord Injuries (SCI) will be equipped with Functional Electrical Stimulation (FES) devices, which will enable them to perform a pedaling movement on a cycling device in order to ride along a circular course. These are the characteristics of the course:
- The circular course will be about 200 m long (i.e. one round in the Kolping Arena, Zurich; the arena size is 80 m by 40 m). There will be 2 or 3 lanes; each of them will have a width of 122 cm.
- The ground of the circular course should have good friction properties to avoid drifting in the curve. The flexing resistance will be low, to avoid too much energy dissipation due to rolling.
- A start ramp with a negative slope will be used to overcome the initial acceleration problem in FES cycling. The dimensions of the ramp are still to be defined.
- There will be two categories of sub-disciplines. The first one will be a sprint race, over a distance of 200 m (about one round in the stadium). The second one will be an endurance race over the distance of 1000 m (about 5 rounds taking about 60 – 80 s per round). Each single pilot will have to participate in both disciplines. Scores will be added to determine the overall winner. To overcome muscle fatigue and possible performance loss of the pilot, the races will start with the short-distance category.
- Two or three competitors will start together. Maximally three can start next to each other when using three lanes. The first one reaching the finishing line will be the winner of the race.
- Depending on the number of participating pilots, further races will be performed with the winners of previous races.
- One person from each team should accompany the pilot during the race to take care of the pilot in case of an emergency (e.g. tilting). If they tilt, the accompanying person will be allowed to rectify the pilot and her/his bike and the pilot will be allowed to continue the race.
- If a cycle device stops due to a technical problem or tilting, and if the pilot cannot restart with his or her own force, the accompanying person will be allowed to slightly push the pilot. For each push the pilot will get a penalty time of 5 s directly verified by a standing pause (or added at the final score).
- The pilots can build up their muscles in FES training prior to the race. During the race, besides strength, also the temporal apportionment of strength will play a crucial role to minimize muscle fatigue effects.
Inclusion Criteria for the Pilots
Participating pilots must fulfill the following inclusion criteria
- Pilots must have paraplegic or tetraplegic lesions due to spinal cord injury, above 12th thoracic segment (T12). Most competitors are expected to be in the category of mid-thoracic paraplegia.
- ASIA A or B, with a complete loss of motor function (http://www.sci-info-pages.com/levels.html). The pilots will have to give testimony about the completeness of their lesion. A stimulator-based test will be developed and applied to confirm completeness of the lesion.
- The lower motor neuron will have to be intact, thus the lesion must be spastic (rather than atonic)
- Pilots will have to have sufficient voluntary control of trunk, arm and neck to be able to steer the bike and stabilize the upper body while riding over uneven terrain and curves.
- Pilots must be at least 18 years old.
Inclusion Criteria for the Technology
The following criteria should apply for the bicycle and FES technology:
- A passive cycling device without any motor will have to be used. The only actuation will be provided through the FES-stimulated legs of the pilot. Arms must not be used to support the propulsion (but for steering).
- The FES stimulator can be commercially available or self-designed. If it is self designed, it will have to fulfill the standard rules for electrical safety. Stimulation devices will have to fulfill the latest IEC standards 60601-1 and 60601-2-10 which describe particular requirements for the basic safety and essential performance of transcutaneous nerve and muscle stimulators. If the participating teams do not certify the stimulator against these standards, they will be required to provide serious and complete documentation and quality control process.
- Any control strategy or stimulation pattern will be allowed to be used for stimulating lower extremity muscles such as quadriceps, hamstrings, gluteals and calf muscle groups. It will not be necessary to stimulate all these muscles (adapted from FES Sports Day.pdf).
- FES stimulation intensity can be adjusted by the cycling athletes during the race so that they can apply their own strategy to minimize muscle fatigue effects.
- Surface and implanted stimulation technologies will be allowed. To ensure that technology is safe, that safety standards are met and that any health risks are avoided, participating teams must have expert approval (e.g. CE, FDA) or an approval from a clinical expert if it is a development technology.
- The number of stimulation channels will not be specified.
- The FES stimulators can apply closed-loop control strategies using sensors applied to the pilot or bike.
- FES stimulators and required sensors will have to be powered by batteries, which will have to be embedded in the cycling device. External power supply will not be allowed.
- The cycling device structure and functioning can be optimized for better mechanical efficiency.
- The number and size of wheels will not be specified. Bikes with two wheels may use stabilizing wheels to avoid tilting.
- Maximum width of the cycling device will be limited to 90cm to enable proper use on the ramps and lanes, and transfer through doors.
- Power and controller will have to be on board the bike or worn by the pilot. Any remote connection to the stationary team members is forbidden
- The pilot’s team must fulfill predetermined safety criteria about the technology that is going to be used during the race. The participating pilot and team must commit to the rules and inclusion/exclusion criteria of the device and prove technical function and safety prior to the race by submitting photographs with longshots and clear close-up views, videos, certification of local boards, risk analysis etc.