Space Nutrition

NASA research has long identified key nutrients that support astronauts in zero-gravity environments to mitigate muscle loss. Clinical data has now demonstrated that targeted nutritional supplementation to be effective in orthopaedics to preserve muscle mass and improve strength post surgery.

High performance athletes, along with elderly patients, face the demands of minimizing muscle loss post injury or surgery in order to return to previous activity levels. The ultimate goal for orthopedic patients is return to functional recovery, which is predicated on regaining muscle volume and strength.

(*download pdf here)

Microgravity causes significant muscle loss and weakness even after just one month of exposure.

Astronauts exposed to microgravity experience:

1 month

  • 20% decrease skeletal muscle mass.
  • 30% decrease skeletal muscle strength.

6 months-1 year

  • 8-10 years of MSK degeneration

The preservation of muscle mass and reduction of strength loss during bedrest and spaceflight have been demonstrated in multiple studies through the use of essential amino acid supplementation.

  • NASA studies aimed to preserve muscle mass have demonstrated Targeted Nutritional Supplementation to preserve muscle loss even in extreme conditions such as 28 of days of bed rest.

    J Clin Endocrinol Metab 2004(4)

  • Targeted nutritional supplementation can improve muscle gain in the most challenging patients.

    HIV patients who were supplemented with ARG/GLUT/HMB for 8wks had a significant increase in LBM in comparison to placebo.

    Clark JPEN May-Jun 2000 (5)

Skeletal Muscle Mass

Dynamic balance between:

Muscle Protein Synthesis (MPS)


Muscle Protein Breakdown (MPB)

The balance between muscle protein breakdown (MPB) and muscle protein synthesis (MPS) largely determines skeletal muscle mass, with both processes occurring continuously and simultaneously. 

Proteins in muscle tissue undergo constant remodeling through the actions of MPB, which utilizes various proteolytic systems to break down proteins and release amino acids and peptides into the muscle's intracellular pool. However, in healthy individuals, MPS usually offsets MPB, especially after protein meal ingestion, causing hyperaminoacidemia and mechanical loading stress on the skeletal muscle.

There are two main triggers that can activate muscle protein synthesis (MPS): Mechanical Loading and Amino Acid/Protein Consumption.

Each pathway can activate MPS distinctly with adequate stimulation, but the synergistic effect of both can have a more significant impact than either alone.

Advances in nutritional sciences and improved understanding of mechanisms, underlying muscle protein synthesis have lead to practical interventions in orthopaedic surgery such as the XR™ trifecta approach.

Watch this video to learn about MPS:

The XR™ Perioperative Optimization Program takes a trifecta approach:

  • Amino acid supplementation
  • Mechanical loading prehabilitation
  • High-protein diet

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(ref #1) Kortebein P, Symons TB, Ferrando A, et al., J Gerontol A Biol Sci Med Sci. 2008;63(10):1076‐1081.

(ref #2) Kortebein P, Ferrando A, Lombeida J, et al: Effect of 10 days of bed rest on skeletal muscle in healthy older adults. JAMA 2007;297:1772-1774.

(ref #3) Paddon-Jones D, Sheffield-Moore M, Cree MG, et al: Atrophy and impaired muscle protein synthesis during prolonged inactivity and stress. J Clin Endocrinol Metab 2006;91:4836-4841

(ref #4) Paddon-Jones D, Sheffield-Moore M, Urban RJ, et al: Essential amino acid and carbohydrate supplementation ameliorates muscle protein loss in humans during 28 days bedrest. J Clin Endocrinol Metab 2004;89:4351-4358

(ref #5) Robert. H. Clark MD, J Parenter Enteral Nutr May-Jun 2000;24(3):133-9.Nutritional Treatment for Acquired Immunodeficiency Virus-Associated Wasting Using β-Hydroxy β-Methylbutyrate, Glutamine, and Arginine: A Randomized, Double-Blind, Placebo-Controlled Study

(ref #6) Gao R, Chilibeck PD. Nutritional interventions during bed rest and spaceflight: prevention of muscle mass and strength loss, bone resorption, glucose intolerance, and cardiovascular problems.Nutr Res. 2020;82:11-24. doi:10.1016/j.nutres.2020.07.001