(CNN) -- How on earth could a teenage swimmer at her first Olympic Games knock five full seconds off her previous best performance? That's what has left so many people scratching their heads after watching China's Ye Shiwen smash the world record in the women's 400-meter individual medley. The Chinese swimming prodigy's extraordinary swims during the first few days of the Olympics may have drawn praise from across the sport, but they've also raised suspicions of drug doping. The 16-year-old world champion won gold Tuesday in the women's 200-meter individual medley, three days after coming from behind to take one second off the world record -- and a whopping five seconds off her personal best -- during her gold medal swim in the 400-meter individual medley.
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China's Ye Shiwen wins second gold in London Tuesday in 200m individual medley
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16-year-old beat 400m individual medley world record by a second on Saturday
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John Leonard called Ye's swim 'unbelievable' and 'disturbing'
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IOC spokesman calls doping allegations 'sad' and 'pure rumor'
But while Ye's swimming has caused the most controversy in the first week of the @placeholder, the swimming prodigy herself isn't exactly an unknown quantity.