Thomas represented Kiribati in the men's 85 kg event at the 2004 Summer Olympics in Athens. He was, at that time, ranked 63rd in the world. He finished 13th, having lifted 292.5 kg. He was also his country's flagbearer during the Opening Ceremony. He had previously won gold in the same event at the 2003 South Pacific Games in Suva. He did not take part in the 2008 Olympics.