Table 2.
Human Spaceflight and Skeletal Adaptations.
| Author | Yr | Space Era | N (Gender) |
Flight Duration |
Exercise Countermeasures | Highlighted Adaptations |
|---|---|---|---|---|---|---|
| Whedon [23,32] | 1976 | Skylab 2 | 3M | 28 d | Bicycle Erg | ↑Urinary calcium, ↑hydroproxyproline, ↑nitrogen and phosphorus excretion |
| Whedon [23,32] | 1976 | Skylab 3 | 3M | 59 d | Bicycle Erg., MK-I, MK-II | ↑Urinary calcium, ↑hydroproxyproline, ↑nitrogen and phosphorus excretion |
| Whedon [23,32] | 1976 | Skylab 4 | 3M | 84 d | Bicycle Erg., MK-I, MK-II, Thorton Passive Treadmill | ↑Urinary calcium, ↑hydroproxyproline,↑nitrogen excretion, phosphorus excretion |
| Stupakov [33] | 1984 | Salyut 6 | 8(NR) | 75–184 d | KTF and penguin suit | Calcaneus BMD (Photon absorptiometry): ↓0.9% to19.8% |
| Organov [34] | 1991 | Salyut 7 | 7(NR) | 4–8 mo | NR | Lumbar spine BMD (CT): ↓−7.5% to −10.8% |
| Miyamoto [16] | 1998 | STS | 2(1M1F) | 8–14 d | Cycle Ergometer | Spine (DEXA): ↓3%, ↓Metacarpal (MD): 1%–3% |
| Smith [35] | 1999 | STS/MIR | 3M | 115 d | NR | ↑50% Urinary calcium, ↑50% Collagen crosslink excretion |
| Vico [36] | 2000 | MIR | 15(14M1W) | 1–6 mo | Not Reported | BMD(DEXA):↓1.8% Tibial cortical bone, BMD(DEXA):↓5.4% Tibial cancellous bone |
| Leblanc [37] | 2000 | MIR | 18(17M1W) | 4–14 mo | Bunge Resistance, Treadmill, Cycle Ergometer | Total BMD(DEXA): ↓0.35% per month, Trochanter BMD(DEXA): ↓1.56 per month |
| Smith [38] | 2004 | ISS | 11(9M2W) | 128–195 d | NR | ↓25-hydroxycholecalciferol, ↑75% deoxypridinoline, ↑40% n-telopeptide |
| Smith [39] | 2005 | STS/MIR | 13(12M1F) | 4–6 mo | NR | N-telopeptide, pyridinoline, and deoxypyridinoline ↑>55% above preflight levels |
| 2005 | STS/MIR | 6M | 4–6 mo | NR | Calcium absorption ↓49% in-flight | |
| Lange [40] | 2004 | ISS | 14(13M1W) | 4–6 mo | NR | Hip aBMD(DEXA): ↓1.4%–1.5% per month, Spine vBMD(QCT):↓0.9% per month |
| Smith [31] | 2012 | ISS | 8(6M2W) | 48–215 d | CEVIS, TVIS, iRED | Total BMC(DEXA):↓4%, Total BMD(DEXA): ↓3%, Pelvic BMC(DEXA): ↓12% |
| Smith [31] | 2012 | ISS | 5(3M2F) | 48–215 d | CVIS, TVIS, ARED | Total BMC(DEXA):↓1%, Total BMD(DEXA): ↔0%, Pelvic BMC(DEXA): ↓2% |
STS = Space transport system, ISS = International space station, CEVIS = Cycle ergometer with isolation system, TVIS = Treadmill with isolation system, iRED = Interim resistive device, VELO = Russian velociped bicycle exercise device, DEXA = Dual x-ray absorptiometry, BMD = Bone mineral density, BMC = Bone mineral content, QCT = Quantitative computer tomography, CT = Computer tomography, d = Days, Yr. = Year, mo = Months, KTF = Exercise device (acronym unknown), M = Men, W = Women, NR = Not reported.