In an attempt to investigate the role of the endogenous opioid peptides in substrate utilization and hormonal responses to exercise, eight trained cyclists completed two exercise trials at each of two distinct intensity/duration combinations. Briefly, cyclists completed two trials at 70% VO2max for 90 minutes and two trials at 90% VO2max until exhaustion. Trials were conducted following the administration of the opiate antagonist naloxone (NAL) (0.1 mg-kg-1 bolus + 0.1 mg-kg-1-·hr-1) or volume matched saline (SAL). Serum glucose was maintained at significantly higher levels at 60 and 90 minutes of exercise in 70% NAL vs 70% SAL. Serum glucose was significantly higher at all points during exercise and at 30 and 60 minutes of recovery in 90% NAL vs 90% SAL. Serum insulin was not altered by naloxone administration at either 70% or 90% trials. Serum Cpeptide was significantly higher at 60 and 90 minutes in 70%-NAL vs 70% SAL, and was significantly lower during exercise in 90%-NAL vs 90% SAL. Plasma glucagon was not different during exercise in the 70% trials, but was significantly higher during exercise in 90%-NAL vs 90%-SAL. The glucagon:insulin molar ration was not significantly altered by naloxone administration in any trial. Rating of peceived exertion was significantly higher during exercise in 70%-NAL, but was not different during exercise in the 90% trials. However, time to exhaustion was significantly (18%) reduced in 90%-NAL vs 90%-SAL. No systematic differences were observed in the cardiorespiratory responses to exercise at either intensity, although pulmonary ventilation was modestly (7%) elevated in 90%-NAL. Thus, opiate antagonism prevents the decline in serum glucose seen in prolonged exercise without altering substrate oxidation, and with minimal influence on the pancreatic hormone response. In contrast, opiate antagonism potentiates the hyperglycemic response to high intensity exercise at least in part by altering pancreatic hormone responses which may contribute to the hyperglycemia. / School of Physical Education

Thesis (M. Phil.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 99-[110]).

Thesis (M. Phil.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 79-98).

Thesis (M.Phil.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 99-[110]) Also available in print.

abstract: The thrill of a live performance can enhance endorphin, serotonin, dopamine, and adrenaline levels in the body. This mixture of heightened chemical levels is a result of "performance adrenaline." This phenomenon can positively and/or negatively affect a performing singer. A singer's body is her instrument, and therefore, any bodily change can alter the singing voice. The uptake of these chemicals can especially influence a central aspect of singing: breath. "Performance adrenaline" can induce shallow or clavicular breathing, alter phonation, and affect vibrato. To optimize the positive effects and counteract the negative, diaphragmatic breathing, yoga, and beta-blockers are explored as viable management tools. When managed properly, the boost offered by "performance adrenaline" can aid the singer in performing and singing. After a review of medical and psychological studies that reveal the physiological and emotional effects of endorphins, serotonin, dopamine, and adrenaline, this paper will explore the biological changes specific to vocalists and methods to optimize these effects in performance. / Dissertation/Thesis / Doctoral Dissertation Music 2015

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Because endorphin receptor activation alters the function of the central noradrenergic system, opiates may change the regenerative sprouting of neurons in response to adrenergic neurotoxins. To test this hypothesis, newborn rats were treated with several opioids and 6-hydroxydopa (6-OHDOPA) and the development of the noradrenergic system was evaluated. In combination with 6-OHDOPA morphine and naloxone potentiated the development of norepinephrine (NE) levels in the pons-medulla and cerebellum by four weeks of age. β-Endorphin, Leu- and Met-enkephalin and d-Ala2-enkephalinamide produced a similar effect in the pons-medulla. The effect of morphine was partially attenuated by naloxone. Increased cerebellar noradrenergic histofluorescent staining was observed with the morphine + 6-OHDOPA and naloxone + 6-OHDOPA treatments. Both naloxone and morphine decreased NE levels in the pons-medulla of adult rats treated with 6-OHDOPA. These results suggest that opiates and endorphins may enhance sprouting of noradrenergic neurons following neonatal treatment with 6-OHDOPA, by increasing the toxicity of this neurotoxin.

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Title: Effect of passive stretching on current patient's mental state Objectives: This thesis presents a pilot theoretical - empirical experiment, where the main subject of the experiment is to evaluate the effect of passive stretching hypertonic or shortened muscles, i.e. decreased muscle tone on current patient's mental state. The theoretical part summarizes the neurophysiologic basis of emotions by search form. Through the implementation and follow-up experiment, we aim to demonstrate the positive impact of stretching exercise on current psychological state. Methods: Two groups of patients participated in this research, thirty without pain and thirty with pain. We chose questionnaire PANAS-X (Watson, Clark, 1994) to diagnose their current mental state. The first group, patients without pain, completed the questionnaire before and immediately after the experimental intervention, i.e. passive stretching hypertonic muscles. The second group, patients with pain, went through stretching exercise unit twice a week for three weeks. As for this group, we compare the situation before the first therapy with the state after six sessions. We evaluated the change in the individual sublevels of positive and negative emotions by the methodology of the questionnaire. Results: During the experiment three out of...

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