Guimard was an ardent advocate of modern methods of rider preparation. LeMond described him as the first professional cycling coach to formally study physiology in order to apply it to rider training. He also took riders to the Equipe Renault Elf Formula One team's wind tunnel to perfect their positioning on the bike and maximise their aerodynamic efficiency. Guimard's wind tunnel work with Hinault led to the development of the Gitane Profil, the first bike to use teardrop-shaped tubes and handlebars, which Hinault claimed gained him one and a half seconds per mile in time trials, and he also experimented with internal cabling. His interest in aerodynamics also led to his teams introducing other innovations in bicycle design during the 1980s, including sloping bike frames and disc wheels. At the 1986 Tour de France, his rider Thierry Marie won the prologue by a quarter of a second with the aid of a "lower back rest" on his bicycle which functioned as an aileron to reduce aerodynamic drag, although the design was subsequently banned.