The 35-year-old announced in May he had taken up kayaking in a bid to become the first person this century to compete in three different Olympic sports.
Taufatofua has already represented his country in taekwondo and cross-country skiing but he admits his bid to qualify for Tokyo in a new discipline is not going well.
Competing in heat five of the K1 200m sprint, Taufatofua, who has been struggling just to stay upright in his kayak, said he registered a personal best of 58.19 seconds. It was still the slowest time of all the heats.