California Gov. Arnold Schwarzenegger pulled out of an environmental conference Saturday to have his knee examined after injuring himself while exercising.

The governor had been scheduled to co-host a climate change summit in South Lake Tahoe, but Sen. Dianne Feinstein told the crowd Saturday morning that Schwarzenegger had called her to say he couldn't make it.

He injured his knee while working out and it has been bothering him all week, Schwarzenegger spokesman Matt David said. A doctor was expected to examine Schwarzenegger's knee for a possibly torn meniscus at the governor's home in Los Angeles.

The 61-year-old bodybuilder-turned-actor-turned politician has suffered numerous physical injuries over the years, most recently when he shattered his femur during a skiing accident in 2006.