Related Experiment Video
Updated: Nov 30, 2025
Conducting Maximal and Submaximal Endurance Exercise Testing to Measure Physiological and Biological Responses to Acute Exercise in Humans
Published on: October 17, 2018
Effects of theophylline and theobromine on exercise performance and implications for competition sport: A systematic
1Department of Clinical Pharmacology and Toxicology, St. Vincent's Hospital Medical School, UNSW, Sydney, Australia.
Abstract:
A systematic review was undertaken to evaluate studies on the effects of theophylline and theobromine on exercise performance in normal (healthy) subjects. Theophylline was found to have been studied on eight occasions and theobromine on one, the number of subjects per study ranging from seven to 15. In two exercise investigations, theophylline was superior to placebo at a p < 0.05 level and no different in four including one that was conducted in artificial hypoxia. In a treadmill time trial over 3 km, theobromine was superior to placebo and equal to caffeine, at the <0.05 level. In strength studies, theophylline increased wrist strength in one and showed a slight but not statistically significant increase in limb strength in four of the seven subjects in the other. Theophylline caused adverse effects in six participants. There were no adverse effects in the theobromine investigation. Although the studies showed contradicting results and/or insufficient data to draw solid conclusions, it appears both drugs have potential to enhance performance and could be considered for inclusion on the WADA banned list.
More Related Videos
07:40Impact of High-intensity Interval Exercise and Moderate-Intensity Continuous Exercise on the Cardiac Troponin T Level at an Early Stage of Training
Published on: October 10, 2019
10:00Supramaximal Intensity Hypoxic Exercise and Vascular Function Assessment in Mice
Published on: March 15, 2019
Related Concept Videos
01:24Antiasthma Drugs: Methylxanthines
Theophylline is thought to inhibit phosphodiesterase enzymes, increasing intracellular levels of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). This rise in cAMP and cGMP concentrations stimulates cardiac function,...
01:20Exercise and Cardiovascular Response
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...
01:28Adrenergic Agonists: Mixed-Action Agents
Ephedrine and pseudoephedrine lack a catecholamine group, making them less susceptible to degradation by metabolic enzymes. They have increased oral bioavailability and lipophilicity, resulting in a longer duration of action. Their response is reduced by...
01:27Adrenergic Antagonists: Pharmacological Actions of β-Receptor Blockers
01:29Pathophysiology of Cardiac Performance
01:27Exercise and Muscle Performance
Endurance exercises
Endurance exercises involve running, swimming, or cycling, which require repetitive movements with low force output. When a person engages in endurance exercise, a few noticeable changes occur in their skeletal muscles. For instance, the number of capillaries...