After 136 hectic days in space, outgoing station commander Bill Shepherd and his two cosmonaut colleagues, Yuri Gidzenko and Sergei Krikalev, were happy to shift into low gear.

"We've been very busy on our expedition, and we're kind of enjoying a somewhat slower pace today," Shepherd told reporters during a space-to-ground news conference. "So I think that's good for us. We're happy to stay one more day."

After all, Gidzenko and Krikalev, both of whom are veterans of long stays on the Russian space station Mir, already are warning him about the tough days ahead.

Now at the tail end of his first long-duration spaceflight, Shepherd will be weak and woozy when he returns to normal gravity after four-and-a-half months in weightlessness.

"To be honest, I'm not that anxious to see what it's going to be like," Shepherd admitted. "Sergei and Yuri have done this before, and they're telling me it's going to be arduous."

Launched Oct. 31 from Baikonur Cosmodrome in Kazakhstan, the so-called Expedition One crew is in the home stretch of a "shake-down cruise" aboard the international station.

A relief crew that includes incoming Russian skipper Yuri Usachev and two American flight engineers, Susan Helms and Jim Voss, is replacing the trio.

Between now and late July, the three Expedition Two crew members will be busy outfitting the newly arrived U.S. Destiny science laboratory, starting up the station's first research experiments and overseeing further outpost construction.

"That is a long time to be away from home no matter where you are -- if you're just on a business trip or if you're in space. But I'm looking forward to the work we're going to be doing up here," Voss said.

"I'm just anxious to get started," he added. "And I hope that it's going to be a great four-and-a-half months for Susan and Yuri and myself."

During their tenure at the station, Shepherd and company started up all crucial life support and other key operational systems while overseeing the delivery and activation of a $600 million U.S. electric power tower and the $1.4 billion Destiny lab.

The former Navy SEAL said he was proud of those accomplishments and happy that people now refer to the station by the radio call sign "Alpha," which was selected by the crew shortly after a Nov. 2 arrival at the outpost.

"We did basically put the space station in commission [and] we gave it a name that seems to be sticking," Shepherd said. "We have taken something that was an uninhabited outpost and we now have a fully functional station where the next crew can do research. And I think that's the substance of our mission."

The joined crews will set out late Friday to finish packing up the Leonardo cargo carrier.

That job entails hauling 1,644 pounds (740 kilograms) of dirty laundry, dead batteries, empty food containers, surplus gear and other garbage into the pressurized freighter, which is to be stowed back in Discovery's cargo bay Saturday night.

A formal farewell and command handover ceremony now is scheduled to take place at 8:27 p.m. EST Sunday (01:27 GMT Monday), a few hours prior to Discovery's delayed departure from the outpost.

With Shepherd and his Russian crewmates in tow, Discovery now is scheduled to land here at Kennedy Space Center at 12:55 a.m. EST (05:55 GMT) Wednesday.

"The first thing I plan on doing when I get back to Earth is saying hi to my wife and playing with my two dogs," Shepherd said.

The two cosmonauts have similar plans, but after a season of sponge baths, Gidzenko has one other pressing want.

"I'm going to meet with my family, my wife and my sons," he said. "And then a little bit later, I'm going to take a shower."