European Journal of Applied Physiology and Occupational Physiology

, Volume 65, Issue 5, pp 394–398

Branched-chain amino acid supplementation during trekking at high altitude

The effects on loss of body mass, body composition, and muscle power
  • F. Schena
  • F. Guerrini
  • P. Tregnaghi
  • B. Kayser
Article

DOI: 10.1007/BF00243503

Cite this article as:
Schena, F., Guerrini, F., Tregnaghi, P. et al. Europ. J. Appl. Physiol. (1992) 65: 394. doi:10.1007/BF00243503

Summary

To investigate the influence of a branched-chain amino acid (BCAA) supplementation on chronic hypoxia-related loss of body mass and muscle loss, 16 subjects [age 35.8 (SD 5.6) years] participating in a 21-day trek at a mean altitude of 3,255 (SD 458) m, were divided in two age-, sex- and fitness-matched groups and took either a dietary supplementation of BCAA (5.76, 2.88 and 2.88 g per day of leucine, isoleucine and valine, respectively) or a placebo (PLAC) in a controlled double-blind manner. Daily energy intake at altitude decreased by 4% in both groups compared with sea level. After altitude exposure both groups showed a significant loss of body mass, 1.7% and 2.8% for BCAA and PLAC, respectively. Fat mass had decreased significantly by 11.7% for BCAA and 10.3% for PLAC, whereas BCAA showed a significantly increased lean mass of 1.5%, as opposed to no change in PLAC. Arm muscle cross-sectional area tended to increase in BCAA, whereas there was a significant decrease of 6.8% in PLAC (P<0.05 between groups). The same tendency, although not significant, was observed for the thigh muscle cross-sectional area. On the whole it seemed that PLAC had been catabolizing whereas BCAA had been synthesizing muscle tissue. Single jump height from a squatted position showed a similar tendency to increase in both groups. Lower limb maximal power decreased less in BCAA than in PLAC (2.4% vs 7.8%, P<0.05). We concluded that BCAA supplementation may prevent muscle loss during chronic hypobaric hypoxia.

Key words

Branched chain amino acid supplementationAltitudeTrekkingLoss of massBody compositionHypoxiaNutrition

Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • F. Schena
    • 1
  • F. Guerrini
    • 2
  • P. Tregnaghi
    • 2
  • B. Kayser
    • 3
  1. 1.Institute of Human PhysiologyUniversity of VeronaVeronaItaly
  2. 2.Institute of Sports MedicineVeronaItaly
  3. 3.Department of Physiology, CMUGeneva 4Switzerland