Research

Mixed

High-load resistance exercise combined with adequate energy and vitamin D intake maintains bone mineral density during long-duration spaceflight, whereas lower-load resistance exercise without optimized nutrition fails to prevent bone loss.

To maintain bone health in microgravity, you must perform high-load resistance exercises (up to 600 lbs) at least 6 days a week, combined with eating enough calories and protein to maintain body weight and taking vitamin D. Low-load exercise or aerobic activity alone will not stop bone loss.

GoodSupportsHIGH confidence
These data document that resistance exercise, coupled with adequate energy intake (shown by maintenance of body mass determined by dual-energy X-ray absorptometry [DXA]) and vitamin D, can maintain bone in most regions during 4- to 6-month missions in microgravity.
Scott M. Smith et al. · Journal of Bone and Mineral Research · 2012

Why this rating

Observational cohort study with a small sample size (n=13) and historical controls, but with rigorous biochemical and densitometry measurements.

Source

Benefits for bone from resistance exercise and nutrition in long-duration spaceflight: Evidence from biochemistry and densitometry

Scott M. Smith et al. · Journal of Bone and Mineral Research · 2012

DOI 10.1002/jbmr.1647

cohort · n=13Cited 339×
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DOI resolved against Crossref · corpus check 2026-06-10

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