President Barack Obama is getting plenty of exercise to start the year.

The president worked out for about an hour at Marine Corps Base Hawaii yesterday before playing a round of golf with friends at Luana Hills Country Club.

The scenic links are located in a lush valley along the Koolau mountains, a few miles from the oceanside home that Obama is renting.

Obama golfed with friends Marty Nesbitt, Bobby Titcomb and Mike Ramos, leaving in the motorcade at 6:20 p.m.

Luana Hills also hosted former President Bill Clinton when he was in office.

Yesterday, Obama took time out of his vacation to sign into law one of the surprise accomplishments of the lame-duck Congress: a measure covering the cost of medical care for rescue workers and others sickened by toxic fumes and dust after the 2001 terrorist attack on the World Trade Center.

"We will never forget the selfless courage demonstrated by the firefighters, police officers and first responders who risked their lives to save others," Obama said in a statement. "I believe this is a critical step for those who continue to bear the physical scars of those attacks."

To become law, the bill required Obama’s signature before he returned to Washington tomorrow, so he signed it at his rented beachfront home on Kailuana Place. The official copy was flown to Hawaii by a White House staff member who was traveling here anyway, said deputy press secretary Bill Burton.

Dozens of aides and support personnel have been stationed at the Westin Moana Surfrider in Waikiki while Obama has vacationed here.

Typically before sunup, press aides already have read through the morning news and begun reaching out to reporters. National security staff members prepare an intelligence briefing for Obama, often delivered in person by aides Nick Rasmussen and Ben Rhodes.

Advance teams and Secret Service agents fan out across the island in preparation for any trips the president might take beyond his rental home.

With a five-hour time gap between Honolulu and Washington, the day is sometimes even longer for officials who must tend to concerns in each city.

"It’s not that hard to give the impression that you’ve really been working on vacation when the work keeps coming," said Burton.

Obama and his family are expected to leave Hawaii for Washington, D.C., today.