Journal Article

effect of L-ornithine hydrochloride ingestion on performance during incremental exhaustive ergometer bicycle exercise and ammonia metabolism during and after exercise

Yamada, T, Demura, S, Komatsu, M, Yamaji, S, Morishita, K

2010

Overview

Objectives: L-ornithine has an important role in ammonia metabolism via the urea cycle. This study aimed to examine the effect of L-ornithine hydrochloride ingestion on performance during incremental exhaustive ergometer bicycle exercise and ammonia metabolism during and after exercise. Subjects/Methods: In all, 14 healthy young adults (age: 22.2±1.0 years, height: 173.5±4.6 cm, body mass: 72.5±12.5 kg) who trained regularly conducted incremental exhaustive ergometer bicycle exercises after -ornithine hydrochloride supplementation (0.1 g/kg, body mass) and placebo conditions with a cross-over design. The exercise time (sec) of the incremental ergometer exercise, exercise intensity at exhaustion (watt), maximal oxygen uptake (ml per kg per min), maximal heart rate (beats per min) and the following serum parameters were measured before ingestion, 1 h after ingestion, just after exhaustion and 15 min after exhaustion: ornithine, ammonia, urea, lactic acid and glutamate. All indices on maximal aerobic capacity showed insignificant differences between both the conditions. Results: Plasma ammonia concentrations just after exhaustion and at 15 min after exhaustion were significantly more with ornithine ingestion than with placebo. Plasma glutamate concentrations were significantly higher after exhaustion with ornithine ingestion than with placebo. Conclusions: It was suggested that, although the ingestion of L-ornithine hydrochloride before the exercise cannot be expected to improve performance, it does increase the ability to buffer ammonia, both during and after exercise.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 631/443/319 / 692/700/459/1994 / administration & dosage / Aerobic capacity / Aerobic exercises / Amino acids / Ammonia / Ammonia - blood / Ammonia - metabolism / Athletes / athletic performance / Athletic Performance - physiology / Bicycles / Biological and medical sciences / biomarkers / blood / Body height / Body mass / buffering capacity / buffers / Clinical Nutrition / Cross-Over Studies / Dietary Supplements / Double-Blind Method / Epidemiology / ergogenic aids / Exercise / Exercise - physiology / Exercise Test / Feeding. Feeding behavior / Fundamental and applied biological sciences. Psychology / glutamates / Glutamic Acid / Glutamic Acid - blood / Heart Rate / human nutrition / Humans / Ingestion / Internal Medicine / L-ornithine / L-ornithine hydrochloride / Lactic Acid / Lactic Acid - blood / Male / Medical sciences / Medicine / Medicine & Public Health / Metabolic Diseases / Metabolism / Muscle Fatigue / muscle physiology / nitrogen balance / nitrogen metabolism / nutritive value / original-article / Ornithine / Ornithine - administration & dosage / Ornithine - blood / Oxygen Consumption / Oxygen uptake / Performance enhancement / Physical Endurance / Physical Endurance - physiology / Physical training / Physiological aspects / physiology / Placebos / Public Health / Recovery (Medical) / sports nutrition / Supplements / Time Factors / Urea / Urea - blood / Vertebrates: anatomy and physiology, studies on body, several organs or systems / Young Adult / Young adults