Sorry for the interruption, but the light is composed by photons. My recommendation is that you should check again how much is the photon mass... On the other hand the energy gained thanks to the "light absorption" would mean extra mass (or weight) assuming tristan's head and helmet had quantic behaviour...
Although it's true that the race results proved something! At least he's nearest to the speed of light than us. By the way congrats to tristan!