Lake Biwa Marathon
Sato began running at an early age and represented his junior and senior high schools in Aizuwakamatsu in the 1500 metres and 5000 metres. He entered higher education at Waseda University and began running over longer distance while there. He made his debut in the marathon at the 2000 Lake Biwa Marathon and he came fourth in a time of 2:09:50 hours, which made him the fastest ever Japanese collegiate runner at that time. On his second outing at the 2001 Fukuoka Marathon he was less successful, as he finished out of contention in eleventh place.