Performance optimization in time-trial cycling has traditionally relied on compartmentalized approaches
(aerodynamics, biomechanics, thermoregulation), without dynamic integration of these parameters. This study presents a
novel multiphysics algorithm, coupling in real time biomechanics, aerodynamics, thermoregulation, and structural mechanics
to optimize a cyclist’s position and the design of a time-trial extension for a given course.
The results reveal strong interactions between the cyclist’s posture, pedal-generated power, aerodynamics, and
thermoregulation. This posture, itself modulated by the position of the extensions, interacts with speed and course profile. A
more upright position on the bike, by increasing the hip angle, enhances muscular power production and improves
thermoregulation through increased convection; however, it is accompanied by higher aerodynamic drag, which is detrimental
to performance. Conversely, a more aerodynamic position reduces drag at the expense of muscular efficiency. There is therefore
a trade-off corresponding to an optimal position for a given time-trial course, aiming to minimize course time while respecting
the cyclist’s physiological limits.
Structural and topological optimization of the extension is then performed to reduce its mass and adapt its shape to the optimal
position derived from the multiphysics model. This approach minimizes aerodynamic drag and mechanical stress on the object,
while respecting the cyclist’s ergonomics.
Future perspectives include the integration of dynamic environmental data (wind, humidity) as well as the optimization of
equipment such as helmets and clothing. This tool, validated by robust physical principles, paves the way for applications in
endurance sports and high-performance sports equipment design.