A new overtraining protocol for mice based on downhill running sessions

Abstract

1. The purpose of the present study was to verify whether a downhill running protocol was able to induce non-functional overreaching in > 75% of mice. 2. Mice were divided into control (C), trained (TR) and overtrained (OTR) groups. Bodyweight and food intake were recorded weekly. The incremental load test (ILT) and the exhaustive test (ET) were used to measure performance before and after aerobic training and overtraining protocols. 3. Although the bodyweight of the OTR group was lower than that of the C group at the end of Week 7, the food intake of the OTR group was higher than that of the C and TR groups at the end of Week 8. Evaluation of results from the ILT and ET revealed significant intra- and inter-group differences: whereas the parameters measured by both tests increased significantly in the TR group, they were significantly decreased in the OTR group. 4. In conclusion, this new overtraining protocol based on downhill running sessions induced non-functional overreaching in 100% of mice.

Excessive training impairs the insulin signal transduction in mice skeletal muscles

“…Then, rodents performed the ILT with an initial intensity of 6 m.min −1 at 0% with increasing increments of 3 m.min −1 every 3 min until exhaustion, as defined by the time at which the mice touched the end of treadmill five times in 1 min. Mice were encouraged using physical prodding (Pereira et al 2012, 2014a,b, 2015a,b, da Rocha et al 2015a. If mice became exhausted without completing the stage, the exhaustion velocity (EV; m.min −1 ) was corrected according to Kuipers and coworkers (Kuipers et al 1985).…”

“…The performance evaluations of the experimental groups were performed on week 0 and 48 h after the last sessions of the OT protocols at the end of weeks 4 and 8, and consisted of the rotarod test (Turgeman et al 2008, Pereira et al 2015a, da Rocha et al 2015b, the ILT (Pereira et al 2012, 2014a,b, 2015a,b, da Rocha et al 2015a, the exhaustive test (Pereira et al 2012, 2014a,b, 2015a,b, da Rocha et al 2015a, and the grip force test (Anderson et al 2004, da Rocha et al 2015a,b, Pereira et al 2015a). On week 0, the experimental groups performed the ILT without inclination.…”

“…n = 10 mice/group): control (CT; sedentary mice), overtrained by downhill running (OTR/down; performed the OT protocol based on downhill running), overtrained by uphill running (OTR/ up; performed the OT protocol based on uphill running), and overtrained by running without inclination (OTR; performed the OT protocol based on running without inclination). The CT, OTR/down, OTR/ up, and OTR mice were manipulated and/or trained in a dark room between 06:00 h and 08:00 h (Pereira et al 2012, 2014a,b, 2015a,b, da Rocha et al 2015a.…”

Nonfunctional overreaching and hepatic adaptations of APPL1 and APPL2

“…The resting interval between daily sessions during the eighth week was 4h. The performance evaluations were made on week 0 and 48 h after the last sessions of the OT protocols at the end of week 8 and consisted of a rotarod test 12,14,15 , the ILT 3,12,14,[16][17][18] , an exhaustive test 3,12,14,[16][17][18] and a grip force test 3,12,14,[16][17][18] . The description of these tests and their results were recently published 3 using the same sample as the current study.…”

Hypothalamic endoplasmic reticulum stress of overtrained mice after recovery

“…The animals were maintained in individual cages with controlled temperature (22±2°C) on a 12:12-h inverted light-dark cycle (light: 6 pm to 6 am, dark: 6 am to 6 pm), with water and food (Purina chow) available ad libitum. The experimental procedures were approved by the Ethics Committee of USP (ID 14.1.873.53.0) and the experimental groups were manipulated and/or overtrained in a dark room between 6 to 8 am 13,[18][19][20][21][22] .…”