Rittweger et al. 2010's own prose describes 56-day bed-rest cortical loss as delayed-onset and steady at both tibial sites, not front-loaded and decelerating

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Read directly, Rittweger et al. 2010's descriptive language for the control arm's cortical loss during 56 days of bed rest points away from a front-loaded, decelerating trajectory at both tibial sites it measured — the Berlin BedRest study being Böcker et al. 2026's reference 22, already read in this vault for its compartment split but not for the shape of the loss over time.

At the distal tibia epiphysis, onset is late rather than early. After establishing that nothing moved in the first two days — "there was no significant change in the bone measurements obtained on days BDC and BR.2," used by the authors to fix their short-term measurement error — the Results report that "cortical BMC started to decline on day BR.17," roughly a third of the way into the 56-day period, while trabecular BMC barely moved during bed rest at all. A loss that does not begin until day 17 is the opposite of a front-loaded curve, which would place the heaviest loss earliest.

At the tibia diaphysis (66% site, Fig. 5), the paper's own word is "continuously": cortical BMC "tended to continuously decrease during the bed rest and until 4 weeks thereafter, and to return to baseline values by 12-month follow-up." That describes a steady decline spanning the whole bed-rest phase and into early recovery, with no inflection noted.

Neither characterization establishes strict linearity: the paper reports no statistic distinguishing a constant rate from a decelerating one, because the numbers underlying these figures were never tabulated (claim-rittweger-2010-bed-rest-time-course-measured-but-not-published-numerically). But delayed onset and a "continuous" decline are both evidence against front-loading — the kinetic that Böcker's dose-equivalence conclusion implicitly requires and that the linearity-vs-deceleration assumption turns on.