NASA-STD-3001 Technical Brief

Relevant Technical 

Requirements

Bone Loss

OCHMO-TB-030

Rev C

NASA-STD-3001 Volume 1, Rev C

[V1 3002] Pre-Mission Preventive Health 

Care

[V1 3003] In-Mission Preventive Health Care

[V1 3016] Post-Mission Health Care

[V1 3017] Post-Mission Reconditioning

[V1 3018] Post-Mission Long-Term 

Monitoring

[V1 4020] In-Mission Nutrient Intake 

[V1 4026] Pre-Mission Bone Mineral Density 

[V1 4027] Pre-mission Bone 

Countermeasures

[V1 4028] Post-Mission Bone Reconditioning

NASA-STD-3001 Volume 2, Rev D

[V2 7038] Physiological Countermeasures 

Capability

[V2 7043] Medical Capability

[V2 7100] Food Nutrient Composition

Executive Summary

Bone density loss in microgravity (skeletal 

unloading) is a well-documented crew health 

concern since the Skylab mission, when it was 

observed that the flight crew had about 1-1.5% 

mineral loss per month. This was noted as being 

“significantly faster than normal osteoporotic 

individuals.” As a result, several technical 

requirements throughout Volumes 1 and 2 of 

NASA-STD-3001 provide countermeasures that can 

aid in the prevention of significant deterioration of 

overall crew heath. This will contribute to overall 

mission success and benefit other areas including 

crew mental well-being. Countermeasures such as 

exercise, adequate nutrition, and medications have 

been recommended or required in order to prevent 

demineralization, especially during long-duration 

missions such as planetary and deep-space 

exploration. Presently, NASA-STD-3001 Volume 1 

Rev C, [V1 4027] Pre-Mission Bone 

Countermeasures provides the range of acceptable 

loss. In addition, there is a need for appropriate 

nutrition to prevent loss from various areas of 

concern, including that of the skeletal, muscular, 

and immunological systems.
NASA-STD-3001 Technical Brief

OCHMO-TB-030

Bone Loss

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Background

Post-flight recovery of bone loss and demineralization can occur over a period of time, but the long-term 

effects (increased risk of osteoporosis) of these changes on the crew are not completely understood, 

especially in crewmembers’ later years following long-duration flights. As missions increase in duration, 

the prevention of bone loss is necessary to avoid injuries or fractures to the crew, especially as more 

strenuous activities are performed, and risks are increased with the exploration of other planetary bodies 

and longer durations of microgravity. 

Exercise as a Countermeasure1

It is noted in the Human Integration Design Handbook (HIDH) Section 5.2.4.2 that “it is critical for 

crewmembers to have frequent access (potentially multiple daily sessions) to exercise equipment that can 

provide high levels of loading, and diversity in load application, on the skeletal system. These exercise 

countermeasures should be targeted primarily toward protecting the lower body and hip regions.” It has 

been observed that the areas of most concern for skeletal unloading are in the lower areas of the body 

(i.e., hips and trochanter). 

As mentioned by Shackelford et al. “Spaceflight can be considered the ultimate model to determine the 

role of gravity on the human skeleton. There is a consensus among exercise scientists that both endurance 

(aerobic) and resistance exercises are needed as countermeasures to maintain overall crew health and 

performance during and after spaceflight. An exercise countermeasure has the advantage of benefiting 

multiple body systems (musculoskeletal, cardiovascular, 

immunological) and can be targeted to those body regions 

needing protection. Maintenance of muscle strength also 

reduces risk of injury during falls and impact. Increased 

muscle strength reduces the risk of impact injury by 

decreasing joint angular velocity, providing damping of 

impact loads. Muscles protect bone from fracture by 

resisting bending moments across long bones.”

11/29/2023

Rev C 2

Grimm et al.

Risk of Bone Fracture 

due to Spaceflightinduced Changes to 

Bone

1. OCHMO-TB-031Exercise Technical 

Brief
NASA-STD-3001 Technical Brief

OCHMO-TB-030

Bone Loss

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Background

3

Reference Information

“Observations of astronauts and cosmonauts indicate that skeletal unloading causes loss of calcium from 

the skeleton, which increases the risk of kidney stones and bone fracture (both during the mission and 

potentially as a lifelong consequence). By using single photon absorptiometry, the bone density of the 

calcaneus in astronauts aboard Skylabs 2, 3, and 4 had a decrease of as much as 8% with an average of 4% 

on the longest flights of 59 and 84 days. Similar observations have been made in cosmonauts, where losses 

in bone density of the calcaneus have been reported to be as much as 19% after 140 days in microgravity” 

(Holick). Additionally, Shackelford et al. reported “to date, we have collected pre-and post-flight bone 

densitometry measurements on 47 individuals from such flights. Although losses show significant 

heterogeneity among individuals and between bones of a given subject, bone loss is a consistent finding 

after spaceflight. Among astronauts and cosmonauts who participated in long duration (average of 170 

days) flights aboard Mir and the ISS, >50% of the crew members had a 10% loss in at least one skeletal site, 

and 22% of the Mir cosmonauts had a 15–20% loss in at least one site. This bone loss has been shown to 

be a regional phenomenon in which the areas with the greatest decrease in weight bearing lose the most 

bone; losses average 1–2%/mo in such regions as the lumbar spine and hip compared with no change in 

the arms or radius (Mir and ISS astronauts, arms: 0.1%/mo; ISS astronauts, radius and ulna: -0.1%/mo).”

11/29/2023

Rev C
NASA-STD-3001 Technical Brief

OCHMO-TB-030

Bone Loss

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

In a review of the information from the Apollo Medical Summit, NASA/TM-2007-214755, it was noted that 

“the astronauts demanded exercise capability for the Command Module for rest and relaxation purposes,” 

which supports Volume 1 of NASA-STD-3001 stating that countermeasures should be used to “mitigate 

undesirable physical, physiological, and psychological effects of space flight upon crewmembers.”

Due to the rarity of persons in microgravity for the purposes of studying bone loss, numerous studies have 

been performed using bed-rest as an analogue to better understand the physiology during skeletal 

unloading, as well as efficacy of various prevention techniques (exercise, medications, diet, etc.). The 

following tables show the results of these studies and the impact of unloading, regardless of the presence 

of microgravity (Tables 1 and 2 from Grimm et al.).

Reference Data

4 11/29/2023

Rev C
NASA-STD-3001 Technical Brief

OCHMO-TB-030

Bone Loss

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Reference Data

5

Application

Information noted in the NASA-STD-3001 Volumes 1 and 2, 

along with details from the HIDH, provide reference details and 

guidance to aid in the understanding of crew needs. Some 

examples that have helped in the implementation of the 

exercise equipment include items from ISS, such as the 

Advanced Resistive Exercise Device (aRED) – This device, while 

similar to the Interim Resistive Exercise Device (iRED), is capable 

of higher concentric resistance and eccentric-to-concentric ratio 

close to that recommended by expert panels and confirmed 

effective by exercise scientists. The aRED also collects data 

regarding the parameters associated with crew exercise and 

transmits it to the ground.

aRED Diagram; NASA, 2012

NASA astronaut Chris Cassidy 

using the aRED device

11/29/2023

Rev C
NASA-STD-3001 Technical Brief

OCHMO-TB-030

Bone Loss

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Application

6

The crew is required to exercise a minimum of time dependent on the program mission as dictated by the 

medical team, however previous requirements have been as little as 2.5 hours per workday with a strict 

exercise program. Additionally, the medical team may instruct the crew to take medication, such as 

bisphosphonates, to prevent bone loss, but this is not currently required for all crew.

Furthermore, the food lab and nutritionists have developed appropriate nutritional foods to ensure that 

the crew have enough micro- and macronutrients to promote crew mental and physical health. The 

interactions of the various technical requirements from both NASA-STD-3001 Volumes 1 and 2, along with 

the supported information from the appendices, will allow for successful missions.1

While it is important to review and update the individual technical requirements that address crew health 

or related areas, considerations should be taken to ensure that all the technical requirements are reviewed 

holistically so they can be applied appropriately for planning and future requirements.

• Treadmill 2 

(COLBERT) – An 

exercise treadmill 

that can also be used 

to collect data such as 

body loading, 

duration of session, 

and speed for each 

crewmember.

CEVIS Diagram; Ambrose et al, 2014

COLBERT Diagram; NASA, 2009

• Cycle-Ergometer with Vibration Isolation System (CEVIS) – A structurally isolated aerobic exercise 

cycle that serves as a countermeasure to cardiovascular deconditioning on orbit.

ESA astronaut Luca Parmitano 

exercising on the COLBERT

ESA astronaut Samantha Cristoforetti exercising 

on the CEVIS

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Rev C

1. OCHMO-TB-013 Food and Nutrition 

Technical Brief
NASA-STD-3001 Technical Brief

OCHMO-TB-030

Bone Loss

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Back-Up

7 11/29/2023

Rev C
NASA-STD-3001 Technical Brief

OCHMO-TB-030

Bone Loss

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Rev B  Rev C

• Updated information to reflect the revisions to language 

throughout both volumes of NASA-STD-3001.

• Updated/added website links due to new NASA website 

launch

Rev A → Rev B

• Updated information to be consistent with NASA-STD-3001 

Volume 1 Rev B and Volume 2 Rev C.

Original → Rev A 

• Overview

• Added executive summary

• Updated standards to Volume 2 Rev B

• Background

• Added subcategory “Exercise as a countermeasure” 

after description in order to have more separation in 

the information

• Added picture to support subcategory for more visual 

interest

• Application

• Added diagrams of exercise equipment for more visual 

interest

• Other

• Added revision page

• Added referenced standards page

Major Changes Between Revisions

8 11/29/2023

Rev C
NASA-STD-3001 Technical Brief

OCHMO-TB-030

Bone Loss

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

NASA-STD-3001 Volume 1 Revision C

[V1 3002] Pre-Mission Preventive Health Care Pre-mission preventive strategies shall be used to reduce inmission and long-term health medical risks, including, but not limited to: (see NASA-STD-3001, Volume 1 Rev C 

for full technical requirement).

[V1 3003] In-Mission Preventive Health Care All programs shall provide training, in-mission capabilities, and 

resources to monitor physiological and psychosocial well-being and enable delivery of in-mission preventive 

health care, based on epidemiological evidence-based probabilistic risk assessment (PRA), individual 

crewmember needs, clinical practice guidelines, flight surgeon expertise, historical review, mission parameters, 

and vehicle-derived limitations. These analyses consider the needs and limitations of each specific vehicle and 

design reference mission (DRM) with particular attention to parameters such as mission duration, expected 

return time to Earth, mission route and destination, expected radiation profile, concept of operations, and 

more. In-mission preventive care includes, but is not limited to: (see NASA-STD-3001, Volume 1 Rev C for full 

technical requirement).

[V1 3016] Post-Mission Health Care Post-mission health care shall be provided to minimize occurrence of 

deconditioning-related illness or injury, including but not limited to: (see NASA-STD-3001, Volume 1 Rev C for 

full technical requirement).

[V1 3017] Post-Mission Reconditioning All programs shall provide the planning, coordination, and resources for an 

individualized post-mission reconditioning program, specific to each crewmember, mission type, and mission 

duration. The post-mission reconditioning starts with crew egress at landing and includes a guided, phased 

reconditioning protocol. The goals of the reconditioning program include the following:

a. To ensure the health and safety of returning crew.

b. To actively assist the crew's return to full functional abilities and return-to-flight status. 

c. To actively assist in the crew’s return to pre-mission fitness 

[V1 3018] Post-Mission Long-Term Monitoring Crewmembers returning from spaceflight shall be monitored 

longitudinally for health, behavioral health, and well-being parameters in a standardized manner. 

[V1 4020] In-Mission Nutrient Intake Programs shall provide each crewmember with 100% of their calculated 

nutrient and energy requirements, based on an individual’s age, sex, body mass (kg), height (m), and appropriate 

activity factor. 

[V1 4026] Pre-Mission Bone Mineral Density Crewmembers’ pre-mission bone mineral density (BMD) T-scores for 

total hip and lumbar spine (L1-L4), as measured by mass dual energy X-ray absorptiometry (DXA) shall be consistent 

with an age, sex, gender, and ethnic-matched population.

[V1 4027] Pre-mission Bone Countermeasures Countermeasuresshall maintain bone mineral density of the hip and 

spine at or above 95% of pre-mission values and at or above 90% for the femoral neck. 

[V1 4028] Post-Mission Bone Reconditioning Post-mission reconditioning shall be aimed at returning bone mineral 

density to pre-mission baseline values.

Referenced Technical Requirements

9 11/29/2023

Rev C

View the current versions of NASA-STD3001 Volume 1 & Volume 2 on the 

OCHMO Standards website
NASA-STD-3001 Technical Brief

OCHMO-TB-030

Bone Loss

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

NASA-STD-3001 Volume 2 Revision D

[V2 7038] Physiological Countermeasures Capability The system shall provide countermeasures to meet 

crew bone, muscle, sensorimotor, thermoregulation, and aerobic/cardiovascular requirements defined in 

NASA-STD-3001, Volume 1. 

[V2 7043] Medical Capability A medical system shall be provided to the crew to meet the medical 

requirements of NASA-STD-3001, Volume 1. 

[V2 7100] Food Nutrient Composition The system shall provide a food system with a diet including the 

nutrient composition that is indicated in the Dietary Reference Intake (DRI) values as recommended by the 

National Institutes of Health, with the exception of those adjusted for spaceflight as noted in Table 7.1-2—

Nutrient Guidelines for Spaceflight.

All referenced tables and figures are available in NASA-STD-3001 Volume 2 Revision D.

Referenced Technical Requirements

10 11/29/2023

Rev C

View the current versions of NASA-STD3001 Volume 1 & Volume 2 on the 

OCHMO Standards website
NASA-STD-3001 Technical Brief

OCHMO-TB-030

Bone Loss

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Reference List

1. National Institutes of Health. Bone Mass Measurement: What the Numbers Mean. 

https://www.bones.nih.gov/health-info/bone/bone-health/bone-mass-measurement-what-numbersmean

2. Apollo Medical Summit, NASA/TM-2007-214755 

3. Shackelford et al. Resistance exercise as a countermeasure to disuse-induced bone loss. J Appl Physiol

97: 119–129, 2004.

4. D Grimm, J Grosse, M Wehland, V Mann, JE Reseland, A Sundaresan and TJ Corydon. The impact of 

microgravity on bone in humans. Bone 87 (2016) 44–56

5. Holick, M.F. 2000. Microgravity-induced bone loss - will it limit human space exploration? Lancet, 

355:1569-70. 

6. Reference Guide to the International Space Station. Utilization Edition September 2015. NP-2015-05-

022-JSC

7. Internation Space Station Facilites: Research in Space 2017 and Beyond. NP-2017-04-014-B-JSC

8. Schneider SM, Amonette WE, Blazine K, Bentley J, Lee SM, Loehr JA, Moore AD Jr, Rapley M, Mulder 

ER, Smith SM (2003) Training with the International Space Station interim resistive exercise device. 

Med Sci Sports Exerc 35(11):1935–1945

9. Hilliard-Robertson PC, Schneider SM, Bishop SL, Guilliams ME (2003) Strength gains following different 

combined concentric and eccentric exercise regimens. Aviat Space EnvironMed 74(4):342–347

10. Smith SM, Heer MA, Shackelford L, Sibonga JD, Ploutz-Snyder L, Zwart SR (2012) Benefits for bone 

from resistance exercise and nutrition in long-duration spaceflight: evidence from biochemistry and 

densitometry. J Bone Miner Res 27(9):1896–1906

11. R. Ambrose, P. Bevill, M. Murray, S. Reddy, D. Blank, and H. Goetz, “Sustaining Engineering Description 

for the Treadmill with Vibration Isolation and Stabilization (TVIS) System,” NASA JSC63712, Rev. B, 2011

12. Human Integration Design Handbook (HIDH), Revision 1. (2014). 

https://www.nasa.gov/sites/default/files/atoms/files/human_integration_design_handbook_revision_

1.pdf

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