Effect of aspartate and asparagine supplementation on fatigue determinants in intense exercise.
OBJECTIVE
This study evaluated the effect of aspartate (ASP) and asparagine (ASG) supplementation on fatigue determinants in Wistar rats exercised to exhaustion by swimming.


METHODS
The animals were tested for anaerobic threshold (AT) determination and then supplemented with 350 mM ASP + 400 mM ASG x day(-1) (AA group, n = 16) or 2 ml x day(-1) of distillated water (PLC group, n = 16) for 7 days. On the 7th day of supplementation, the animals were divided into 4 new groups and killed at rest (RAA, n = 8; RPLC, n = 8), or immediately after the swimming exercise to exhaustion (EAA, n = 8; EPLC, n = 8). R: No significant differences were observed between amino acids and placebo rest groups for muscle and liver glycogen, blood glucose, lactate, alanine, and glutamine concentrations. However, in the exhaustion groups, the EAA group showed higher exercise time (68.37 +/- 25.42 x 41.12 +/- 13.82 min, p <.05) and lower blood lactate concentration (8.57 +/- 1.92 x 11.28 +/- 2.61 mmol x L(-1), p <.05) than the EPLC group. Moreover, the ASP+ASG supplementation decreased the rate of glycogen degradation of gastrocnemius (1.00 +/- 0.51 x 3.43 +/- 0.99 microg x 100 mg of tissue sample(-1) x min(-1), extensor digitorius longus (5.70 +/- 2.35 x 8.11 +/- 3.97 microg. 100 mg of tissue sample(-1) x min(-1) and liver (0.51 +/- 0.34 x 3.37 +/- 2.31 microg x 100 mg of tissue sample(-1) x min(-1) for EAA.


CONCLUSIONS
These results suggest that ASP+ASG supplementation may increase the contribution of oxidative metabolism in energy production and delay fatigue during exercise performed above the AT.
Marquezi
Marcelo Luis
ML
Laboratory of Experimental Nutrition and Metabolism Applied to Physical Exercise in the Physical Education and Sport School at São Paulo University, Brazil CEP 05508-900, São Paulo, Brazil.
Roschel
Hamilton Augusto
HA
dos Santa Costa
André
A
Sawada
Letícia Aiko
LA
Lancha
Antonio Herbert
AH
D000409:Alanine / Q000097:blood; D000818:Animals; D001216:Asparagine / Q000494:pharmacology*; D001224:Aspartic Acid / Q000494:pharmacology*; D001786:Blood Glucose / Q000378:metabolism; D019587:Dietary Supplements; D005973:Glutamine / Q000097:blood; D006003:Glycogen / Q000378:metabolism; D019344:Lactic Acid / Q000097:blood; D008112:Liver Glycogen / Q000378:metabolism; D008297:Male; D018763:Muscle Fatigue / Q000187:drug effects / Q000502:physiology*; D018482:Muscle, Skeletal / Q000378:metabolism; D010805:Physical Conditioning, Animal / Q000502:physiology; D005082:Physical Exertion / Q000187:drug effects / Q000502:physiology*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013550:Swimming
D001786:Blood Glucose; D008112:Liver Glycogen; D005973:Glutamine; D001224:Aspartic Acid; D019344:Lactic Acid; D001216:Asparagine; D006003:Glycogen; D000409:Alanine