Ergolytic Agents: Substances and Other Agents that Impair Performance

Posted on 09 May 2012 01:23

Ergolytic is the opposite of ergogenic. It is derived from the Greek word ergon, meaning "work" and -lytic, which is the adjective form of the Greek word lysos, meaning "loosing, dissolving, or dissolution." The term ergolytic is used to refer to an agent, device, or factor that impairs athletic performance rather than enhances it. This impairment can be the result of physiological or psychological factors. Some common ergolytic agents are alcohol, tobacco (including smokeless), and marijuana.

Some supplements or other products that are thought to be ergogenic for one aspect of performance may be ergolytic for other aspects of performance. For instance, although creatine is thought, with good evidence, to enhance short-term anaerobic metabolism, it has been suggested that this increase could produce more lactate and subject an athlete to more lactic acidosis.

Diet can be potentially ergolytic. A caloric excess resulting in weight gain, for instance, could impair performance for endurance athletes and relative strength athletes. A diet without adequate carbohydrate could impair performance for an endurance athlete, as well. The following sections discuss other potentially ergolytic products.

Beta Blockers

Beta blockers are used as an ergogenic aid in archery and shooting, but will likely impair performance, perhaps greatly, in endurance and strength athletes. These drugs, such as Inderal (propranalol) and Tenormin (atenalo), are used to treat high blood pressure. These drugs attenuate the heart rate and blood pressure response to exercise and also decrease tidal volume, increasing respiratory rate. They can speed time to exhaustion and impair the body's ability to regulate temperature. It is possible that some eye drops used to treat glaucoma, such as timilol, another beta blocker, may be absorbed into the body and worsen performance.

For more on beta blockers see Peformance Enhancing Drugs Other Than Anabolic Steroids Used in Sports. Most of the substance used as ergogenic aids discussed there are also potentially ergolytic, because of their often serious side-effects.

Calcium Channel Blockers

Calcium channel blockers are blood pressure and angina medications such as Diltiazem and Verapamil. They decrease heart rate response to exercise and may decrease myocardial contractility.

Alpha blockers are other blood pressure medications that are potentially ergolytic.


Anthihistamines are commonly used over-the-counter remedies for cold and allergy symptoms such as diphenhydramine, chlorpheniramine, and loratadine. They can cause drowsiness, which would certainly impair performance. They can also decrease psychomotor performance.


Other common over-the-counter medicines may also be ergolytic. Among them are antacids such as Tagamet (cimitidene), which has been found to be anti-androgenic to a small number of men, causing breast enlargement and inhibited sexual function. Interference with testosterone could reduce muscle mass and interfere with performance.


Caffeine is one of the most widely consumed drugs in the world, readily available in coffee, tea, and soft drinks, is also one of the most wildly popular ergogenic aids, with proven benefits to performance. However, it can also become an ergolytic for several reasons.

People who are not used to caffeine or consume it in very large doses may experience nervousness, tremors, restlessness, insomnia, headache, and gastrointestinal problems. Disrupted sleep patterns can obviously impair performance. Since it acts as a diuretic, it may put athletes at risk for dehydration in hot environments. Also, caffeine is physically addictive, and abrupt cessation of use can cause severe headache (caffeine headache), fatigue, irritability and gastrointestinal distress.


Inosine is a purine based nucleotide which is a structural component of ATP. It is obtained in the diet or produced endogenously in the body. It has been marketed as a dietary supplement and claimed by manufacturers to increase ATP stores, and so increase muscle strength and training performance. It has also been said to increase oxygen delivery to the cells to improve endurance. This is based on the role that inosine plays in the formation of 2-3-diphosphoglycerate, a substance in erythrocytes that facilitates the release of oxygen to the tissues. Other benefits have also been postulated. No studies have provided support for these claims or theories and one study found an ergolytic effect, where time to fatigue was decreased. Perhaps more importantly, it increases uric acid levels to amounts associated with gouty arthritis, which cause joint pain, particularly in the knee and foot.


Kenney, W. Larry., Jack H. Wilmore, David L. Costill, and Jack H. Wilmore. Physiology of Sport and Exercise. Champaign, IL: Human Kinetics, 2012.

Baker, Arnie. Bicycling Medicine: Cycling Nutrition, Physiology, and Injury Prevention and Treatment for Riders of All Levels. New York: Simon & Schuster, 1998.

Miller, Mark D., Jennifer A. Hart, and John M. MacKnight. Essential Orthopaedics. Philadelphia, PA: Saunders/Elsevier, 2010.

This page created 09 May 2012 01:23
Last updated 20 Jul 2016 05:03

© 2020 by Eric Troy and Ground Up Strength. All Rights Reserved. Please contact for permissions.