This randomized, double-blind, placebo-controlled study investigated whether 30 days of oral supplementation with a special mixture of amino acids (2 packets of amino acids per day for a total of 8 grams per day), could improve exercise capacity as well as post-exercise recovery of a group of 95 elderly outpatients with congestive heart failure.
Table 1 shows the composition of the oral nutritional mixture. It consisted of the nine essential amino acids and 2 conditionally-essential amino acids. The human diet must contain adequate quantities of nine amino acids (the essential amino acids) because the body cannot synthesize these amino acids in sufficient amounts to meet the metabolic demands of infant growth or to maintain adult health. Conditionally-essential amino acids become essential under certain clinical conditions and can only be synthesized if their indispensable amino acid precursors are provided in the diet.
Table1. Amino acid composition of a single 4 g supplemental packet
Total Amino Acids
The results of this investigation demonstrate that oral supplementation with a mixture of essential and conditionally-essential amino acids along with standard pharmacologic therapy effectively improves exercise capacity in elderly outpatients with congestive heart failure. The investigators conclude that improving circulatory function, increased muscle oxygen consumption, and greater production of energy via aerobic pathways may be responsible for the improved exercise tolerance. Likewise, amino acid supplementation shortened post-exercise recovery by improving circulatory function and quickening the muscle replenishment of energy.
These findings suggest that amino acid supplementation may improve nutritional and metabolic status in patients with congestive heart failure.
- Aquilani R, Viglio S, Iadarola P et al. Oral Amino Acid Supplements Improve Exercise Capacities in Elderly Patients with Chronic Heart Failure. The American Journal of Cardiology 2008;101:S104-S110.