Effect of beta-hydroxy-beta-methylbutyrate, arginine, and lysine supplementation on strength, functionality, body composition, and protein metabolism in elderly women.
OBJECTIVE
With advancing age, there is a gradual loss of muscle mass, strength, and functionality. The current studies were conducted to determine whether a mixture of specific nutrients, arginine and lysine, which support protein synthesis, and beta-hydroxy-beta-methylbutyrate (HMB), which can slow protein breakdown, could blunt the gradual loss of muscle that occurs in the elderly, thus improving strength and functionality.


METHODS
In double-blind studies conducted at two separate sites, women (mean 76.7 y) were randomized to a placebo group (n = 23) or an experimental treatment group (2 g beta-hydroxy-beta-methylbutyrate, 5 g arginine, and 1.5 g lysine daily; n = 27).


RESULTS
After 12 wk, there was a 17% improvement in the "get-up-and-go" functionality test in the experimental group (-2.3 +/- 0.5 s) but no change in the placebo group (0.0 +/- 0.5 s; P = 0.002). The improvement in functionality also was reflected by increased limb circumference, leg strength, and handgrip strength (all P < 0.05) and positive trends in fat-free mass (P = 0.08). Whole-body protein synthesis, estimated with the (15)N-glycine tracer technique over a 24-h free-living period, increased approximately 20% in the experimental treatment group as opposed to the placebo group (P = 0.03).


CONCLUSIONS
These studies indicated that daily supplementation of beta-hydroxy-beta-methylbutyrate, arginine, and lysine for 12 wk positively alters measurements of functionality, strength, fat-free mass, and protein synthesis, suggesting that the strategy of targeted nutrition has the ability to affect muscle health in elderly women.
Flakoll
Paul
P
Department of Health and Human Performance, Vanderbuilt University Medical Center, Nashville, Tennessee, USA. flakollp@iastate.edu
Sharp
Rick
R
Baier
Shawn
S
Levenhagen
Deanna
D
Carr
Christopher
C
Nissen
Steven
S
D000368:Aged; D000369:Aged, 80 and over; D000596:Amino Acids / Q000008:administration & dosage*; D001120:Arginine / Q000008:administration & dosage; D001823:Body Composition; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008239:Lysine / Q000008:administration & dosage; D018482:Muscle, Skeletal / Q000187:drug effects; D017698:Postmenopause; D011795:Surveys and Questionnaires; D016896:Treatment Outcome; D014631:Valerates / Q000008:administration & dosage
D000596:Amino Acids; D014631:Valerates; C004961:beta-hydroxyisovaleric acid; D001120:Arginine; D008239:Lysine