Forced Swim Reliability for Exercise Testing in Rats by a Tethered Swimming Apparatus

Author(s)

dos Reis, Ivan G. M. ^[1] ; Martins, Luiz E. B. ^[2] ; de Araujo, Gustavo G. ^[1] ; Gobatto, Claudio A. ^[1]

Affiliation

^[1] Univ Estadual Campinas, Sch Appl Sci, Lab Appl Sport Physiol, Limeira - Brazil

^[2] Univ Estadual Campinas, Sch Phys Educ, Campinas, SP - Brazil

• Document type: Journal article
• Source: FRONTIERS IN PHYSIOLOGY; v. 9, DEC 19 2018.
• Web of Science Citations: 1

Abstract

To assess the physical capacity of rats in forced swim tests, the animal should perform a continuous activity (CON) at the surface to avoid apnea. Bobbing movement (BOB), vigorous paddling known as climbing (CLI), and diving activity (DIV) are inadequate swimming patterns known to increase the exercise intensity variability, impairing the test reliability. Thus, the exercise work accomplished and related physiological variables, such as the blood lactate concentration, may be unreproducible in forced swim. This study aimed to verify the exercise work reproducibility in rats with a 30-min test-retest at maximal lactate steady state (MLSS) intensity using a tethered-swimming apparatus that analyzes swimming patterns by the direct measurement of swimming force. Additionally, it was determined the swimming force and duration of CON, BOB, CLI, and DIV at physiologically different exercise-intensities. The swimming force at MLSS (n = 64) was 38 +/- 7 gf.Kg(-1), while the blood lactate concentration was 4.2 +/- 1.6 mmol.L-1. In the test-retest (N = 23), swimming force (36.6 +/- 7 gf.Kg(-1) vs. 36.4 +/- 7 gf.Kg(-1)) and blood lactate concentration (4.7 +/- 1.7 mmol.L-1 vs. 4.2 +/- 1.7 mmol.l(-1)) were similar, but only the swimming force was highly correlated (0.90 and 0.31). Although it was not statistically different, the swimming force for CON tends to be slightly lower than CLI and slightly higher than BOB independently of exercise-intensity. The CON pattern predominates (similar to 52.8 +/- 18%) at intensities below and of MLSS but BOB was the swimming pattern more often observed above MLSS-intensity (52.6 +/- 18%). The present study used a tethered swimming apparatus to investigate the reliability of forced swim tests for exercise testing in rats and better understand the swimming patterns when determining the MLSS, but the results can be extended to any study that rely on forced swim for exercise testing and training. The result suggests that, at least at intensities of physiological stability, the exercise work accomplished by rats is reproducible in forced swim, but the blood lactate concentration seems to be affected by other factors, such as the apnea and stress caused by the possibility of drowning, besides the exercise-intensity. (AU)

• FAPESP's process: 11/08284-2 - Acute effect of exercise in the intensity of maximal lactate steady state on protein and mRNA expressions of HIF-1±, MCTs 1 e 4 e PGC-1±, in heart, hepatic and skeletal muscle of swimming rats
• Grantee: Ivan Gustavo Masselli dos Reis
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 08/03445-5 - Analysis of the force and swimming pattern parameters in control and obese rats from a signs acquisition system, in tethered swimming. influence of the exercise intensity and body density
• Grantee: Ivan Gustavo Masselli dos Reis
• Support Opportunities: Scholarships in Brazil - Master