MOSCOW, DEC. 30 -- Cosmonaut Yuri Romanenko grew four-tenths of an inch taller during his record 10 1/2 months in space, and crewmate Alexander Alexandrov grew six-tenths of an inch, a Soviet newspaper said today.

Alexandrov also gained weight, but Romanenko lost a few pounds, including some muscle, according to Sovietskaya Rossiya.

"During prolonged flights in the absence of normal gravity, human height increases," Georgy Grechko, a former astronaut, was quoted as saying. Grechko was at ground control outside Moscow when the cosmonauts landed on a snow-covered steppe in Soviet Kazakhstan yesterday.

Soviet papers said Romanenko, 43, and Alexandrov, 44, would spend the next few weeks at Baikonur cosmodrome in Kazakhstan undergoing medical tests. They were helped from their Soyuz TM3 return spacecraft by doctors and landing crew.

Soviet test pilot Anatoly Levchenko, who returned with them from the space station Mir after just one week in orbit, emerged separately from the craft and then piloted a passenger jet to Moscow as an experiment for a future space shuttle program.

Soviet television today showed extracts from a news conference given by Romanenko, Alexandrov and Levchenko at the Baikonur cosmodrome.

"I feel well. This is no phenomenon, but shows the success of Soviet space medicine," said Romanenko, who looked relaxed and cheerful as he sat between his two colleagues.

He said he was sure the next space mission would last even longer and that a mission to Mars was "getting closer and closer."

The television showed Romanenko walking with his wife, the commentary drawing attention to "his confident stride."

Alexandrov also said he felt fine: "We're not jumping or sprinting -- that's on doctor's orders -- but we are fit."

Levchenko, whose stay in space was the shortest, confessed to a "momentary weakness" after being helped from the space capsule.

"But then, I had spent the previous 15 minutes on my head," he said.