Meeting Abstract

138.1  Monday, Jan. 7  Making Olympic lizards: The effects of sprint and endurance training in lizards HUSAK, J. F.*; KEITH, A. R.; WITTRY, B. N.; Univ. of St. Thomas; Univ. of St. Thomas; Univ. of St. Thomas jerry.husak@stthomas.edu

Exercise training is well known to affect a suite of physiological and performance traits in mammals, but training effects are less clear in other vertebrate groups. We examined performance and physiological differences among green anole lizards that were trained for sprinting or endurance, or not trained at all. Trained lizards underwent an increasingly rigorous training regime over 8 weeks, whereas untrained lizards were handled as a control. Sprint-trained lizards were run an increasing number of times per day, three days a week, on an inclined racetrack. Endurance-trained lizards were run for 30 min per day, three days a week, on a treadmill that was progressively increased in incline. All three groups improved in endurance capacity by at least 10% on average, and all groups decreased in sprint speed on average, but there were post-treatment differences in performance capacity. Lizards trained for endurance had significantly higher post-training endurance capacity compared to the other treatment groups, but groups did not show post-training differences in sprint speed. Acclimation to the laboratory environment and training explain some of our results, but we explored potential mechanistic explanations for these results as well, including differences in hematocrit, heart size, muscle masses, proportion of muscle fiber types, and response of different muscle fiber types to specialized training. Our results offer some caveats for researchers, but they reveal insights into how muscles and performance are impacted by training.