JENNIFER LOPEZ is training furiously to be fit enough to take part in a triathlon, just eight months after giving birth to twins.

The Latina superstar was snapped on vacation in Italy this week (ends11Jul08) with her bikini body back, following the February birth of tots Max and Emme.

And her husband Marc Anthony reveals Lopez is on a tough training schedule; on foot, on bike, and in water.

He tells TV show Extra, "Jennifer is training for a triathlon. In October."

But crooner Anthony confesses he will be watching from the sidelines, instead of working up a sweat with Lopez.

He says, "I'm very supportive. I'll be on my Segway (encouraging her)."