Determination of anaerobic threshold in rats using the lactate minimum test

Autor(es)

F.A. Voltarelli ^[1] ; C.A. Gobatto ^[2] ; M.A.R. de Mello ^[3]

Afiliação do(s) autor(es)

^[1] Universidade Estadual Paulista. Instituto de Biologia. Departamento de Educação Física - Brasil

^[2] Universidade Estadual Paulista. Instituto de Biologia. Departamento de Educação Física - Brasil

^[3] Universidade Estadual Paulista. Instituto de Biologia. Departamento de Educação Física - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Journal of Medical and Biological Research; v. 35, n. 11, p. 1389-1394, 2002-11-00.

Resumo

The break point of the curve of blood lactate vs exercise load has been called anaerobic threshold (AT) and is considered to be an important indicator of endurance exercise capacity in human subjects. There are few studies of AT determination in animals. We describe a protocol for AT determination by the "lactate minimum test" in rats during swimming exercise. The test is based on the premise that during an incremental exercise test, and after a bout of maximal exercise, blood lactate decreases to a minimum and then increases again. This minimum value indicates the intensity of the AT. Adult male (90 days) Wistar rats adapted to swimming for 2 weeks were used. The initial state of lactic acidosis was obtained by making the animals jump into the water and swim while carrying a load equivalent to 50% of body weight for 6 min (30-s exercise interrupted by a 30-s rest). After a 9-min rest, blood was collected and the incremental swimming test was started. The test consisted of swimming while supporting loads of 4.5, 5.0, 5.5, 6.0 and 7.0% of body weight. Each exercise load lasted 5 min and was followed by a 30-s rest during which blood samples were taken. The blood lactate minimum was determined from a zero-gradient tangent to a spline function fitting the blood lactate vs workload curve. AT was estimated to be 4.95 ± 0.10% of body weight while interpolated blood lactate was 7.17 ± 0.16 mmol/l. These results suggest the application of AT determination in animal studies concerning metabolism during exercise. (AU)

• Processo FAPESP: 96/05425-2 - Mecanismos celulares e moleculares envolvidos na secreção e na ação periférica da insulina em diferentes modelos experimentais
• Beneficiário: Maria Alice Rostom de Mello
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 01/03356-3 - Limiar anaerobio e "steady-state" maximo de lactato em ratos durante exercicio de natacao.
• Beneficiário: Fabrício Azevedo Voltarelli
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica