The Washington Post quotes the London Daily Telegraph quoting speculative details about a possible profile for a manned Mars mission. It's a shame the guy from the Telegraph fails to understand what he just wrote (working from NASA notes, obviously) about how much of the mission will be spent in zero-G.
C'mon, guys, Mars has about a third of a gee. For a trip that long, NASA's been talking for years about designing a ship that can be spun on a tether to provide artificial gravity. It would even be entirely feasible to adjust the spin rate during the mission, to vary between a third of a G at the Mars end and about, say, two-thirds G at the Earth end, in both directions. This would likely almost eliminate mineral loss and provide progressive gravity acclimation throughout the trip.
(Linky from koyote)