The Olympic gymnastics competition next year looks wide open after narrow wins saw China\'s men and a young US women\'s squad take the team titles at the world gymnastics championships in Tokyo. The medal table at the end of the 10-day championships on Sunday saw China, who won both men\'s and women\'s team titles at the 2008 Beijing Olympics, finish top with 12 medals, including four golds. The United States also grabbed four golds, with a total medal haul of seven, while hosts Japan and superpower Russia won two titles each. \"Our advantage over other countries is not apparent. Personally I have many things to reflect on,\" 26-year-old Chen Yibing said after winning his fourth world rings title, to add to his Olympic gold. The Chinese men\'s squad, starring Olympic and world champions in different apparatus but lacking all-arounders, lifted their fifth straight world team title with Japan second for the third time in a row. Triple Olympic champion Zou Kai regained the world horizontal bar title, which he lost in his absence last year, by narrowly beating defending champion and teammate Zhang Chenglong. The United States finished third, just one hundredth of a point behind Japan, for their first podium finish since 2003. The team contest went down to the wire and China made sure of their victory only after Japan\'s last two performers, Yusuke Tanaka and all-around champion Kohei Uchimura, fell from the horizontal bar. \"We are a bit short on stability as a team, including myself,\" Uchimura, 22, said on Sunday after wrapping up his campaign with two golds -- including an unprecedented third straight all-around title -- one silver and a bronze. Japan won the Olympic title in 2004 for the first time in 28 years but fell behind China in Beijing. They have been without a world team title since 1978. Jordyn Wieber, 16, led the United States to win the women\'s title for the first time since 2007 and she went on to win the all-around title in the absence of injured Russian holder Aliya Mustafina. The Russian women, led by another 16-year-old, Youth Olympic champion Viktoria Komova, lost their crown, blaming their defeat partly on Komova\'s fitness problem following her leg injury. China were third, as they were last year. Wieber, making up for the absence of injured senior teammates, including world multiple-medallist Rebecca Bross and 2009 all-around champion Bridget Sloan, beat Komova into second spot in the all-around. But Komova won the uneven bars and teammate Kseniia Afanaseva triumphed on the floor. In a boost to the US, McKayla Maroney, who will turn 16 in December, conquered the vault for her first global title. Their squad had been further diluted after Beijing Olympic captain Alicia Sacramone, 24, the 2010 world vault champion, went home for surgery on an Achilles tendon she tore in training. \"It\'s quite exciting to have a younger generation of girls coming up, including myself,\" Wieber said. Romanian-born US team coordinator Martha Karolyi said the team performed well with the squad available, adding she was not worried about the US shortage of event specialists in the run-up to next year\'s Olympics. \"I think gymnastics is about all-around,\" she said, adding that her girls were \"strong\" and endowed with \"all-around power\".