Accession Number : ADA319644

Title :   The Energetics of Non-Sustainable, Burst Locomotion in the Desert Iguana, Dipsosaurus Dorsalis.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH

Personal Author(s) : Nedrow, Jeffrey M.

PDF Url : ADA319644

Report Date : 12 DEC 1996

Pagination or Media Count : 82

Abstract : Excess post-exercise oxygen consumption (EPOC), once known as 'oxygen debt,' has been well documented in a wide variety of organisms. There are many factors implicated as responsible for EPOC. These include elevated lactate and hormone levels, depressed glycogen concentrations, increased body temperature (in endotherms), increased ventilation and heart rate, decreased phosphagen levels, and depressed oxygen concentrations in hemoglobin and myoglobin. Both the intensity and duration of exercise have been found to influence the length and magnitude of EPOC. Most of the previous research done on EPOC has focused on long duration, sustainable locomotion. For many animals, exercise of short duration is more ecologically relevant, yet little is known about EPOC under these conditions. There were three purposes for this study. First, I have focused on determining the influence of exercise duration on EPOC for short, (<= 60 seconds) maximal burst locomotion in the desert iguana, Dipsosaurus dorsalis. I have found that the length and magnitude of EPOC is positively affected by sprint duration. Secondly, I investigated the relationship between the adrenal hormones, epinephrine and norepinephrine, and EPOC. These hormones are known to elevate recovery metabolism and previous research has revealed that these hormones are increased in D. dorsalis following five minutes of treadmill exercise. I have found that administration of the alpha-blocker, phentolamine, and the beta-blocker, propranolol, prior to treadmill exercise significantly reduces EPOC duration and magnitude below saline injected control values. A third purpose of this research was to establish the energetic cost of non-sustainable transport, C(ns), for these animals.

Descriptors :   *ENERGETIC PROPERTIES, *REPTILES, *LOCOMOTION, HORMONES, VENTILATION, THESES, METABOLISM, TIME, NOREPINEPHRINE, MUSCLES, DESERTS, HEMOGLOBIN, HEART RATE, CONCENTRATION(CHEMISTRY), ECOLOGY, SALINE SOLUTION, PHOSPHORIC ACIDS, OXYGEN CONSUMPTION, ENDOTHERMIC REACTIONS, BODY TEMPERATURE, EXERCISE(PHYSIOLOGY), LACTATES, ADRENAL GLANDS, TREADMILLS, GLYCOGEN, CREATINE, EPINEPHRINE, MYOGLOBULIN.

Subject Categories : Biochemistry
      Stress Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE