Looking tired and speaking slowly but firmly, President Boris Yeltsin took the oath of office Friday for his second term, promising to defend democratic freedom.

Dogged by concerns about his health and ability to run his vast country, Yeltsin walked slowly onto the stage of the State Kremlin Palace and stood stiffly before thousands of dignitaries. He spoke loudly, but his speech seemed slurred in an address lasting less than a minute."While carrying out my duties as president of the Russian Federation, I pledge to respect and uphold the rights and freedoms of the individual and the citizen," said Yeltsin, his hand resting on a copy of the Russian constitution.

At a reception afterward, Yeltsin pledged to continue the course he began five years ago, and added, "The people's support gives me the right to act resolutely and firmly."

Yeltsin also promised to bring "prosperity and order" to every Russian home and raised a toast "to the great multi-ethnic Russian people . . . to glorious, thousand-year-old and eternally young Russia."

The ceremony was brief and simple with, aides said, an eye to keeping costs down. But the scaled-back plans again raised questions about Yeltsin's health and stamina.

Aides said Yeltsin - who suffered two heart attacks last year - would start a long vacation after being sworn in. He returned to work just this week from a break begun after last month's election victory.

The president is exhausted after the long campaign, aides say, and simply needs rest. Opposition groups say privately Yeltsin is unlikely to serve a full four-year term and they already are quietly discussing election strategy.

Yeltsin smiled broadly when the presidential chain of office was placed around his neck. Soldiers in blue and black ceremonial uniforms flanked the president; an army band played the national anthem and the choir sang during the 20-minute ceremony.