Steven Lawrence

The extinction of healthy bacteria in our bodies could escalate a new global health crisis. The good news: the field’s top two scientists are on the case, examining the impact microbiomes have on our wellbeing.

Follows six extreme sports stars as they prepare for and then compete in the 2008 Summer X-Games in Los Angeles. Kyle Loza practices a new motocross trick, landing in a pit of foam. Can he do it in front of thousands and land safely on dirt? Travis Pastrana shifts from a bike to a rally car - in part because he's broken so many bones. Shaun White finishes his snowboard season and jumps immediately onto his skateboard. Retired motocross champion Ricky Cunningham takes up a new event. In the finale, after practicing together as friends and competitors, Bob Burnquist and Danny Way face off on the mega ramp