An ambulance was called for Britney Spears' 33-year-old ex after he complained of chest pains while filming a weight loss show in Australia. And local reports say the former dancer suffered a minor cardiac arrest and is now staying in Sydney's Mt Druitt hospital for further tests. Kevin was taking part in a challenge against football club Greater Western Sydney for the Channel 9 show, Excess Baggage, when he complained of a roaring pulse and stabbing pain. Paramedics gave him an oxygen mask before calling an ambulance. A spokesperson for Channel 9 said: "Kevin was at Doonside with the Giants, completing an AFL-related challenge. "He did his challenge, which was running and catching the ball, then while his (in-series weight-loss partner) was taking the same challenge, he reported chest pains and a racing heart. Health scare ... Kevin Federline became ill while filming fitness show Frank Thorne "Obviously on this show we have a lot of paramedics on stan...