Diuretic Therapy and Exercise Performance

Abstract

Drugs that induce an increased urine flow are used both legitimately (treatment of hypertension and oedema) and otherwise (rapid weight loss) in sports and exercise. There are 5 major categories of diuretic drugs based on their mechanisms and loci of action. Common to all classes is hypohydration, which has been shown to have an array of adverse effects on performance, including impaired strength, power and endurance. Postural hypotension can be particularly troublesome in the elderly. Also common to all diuretics, except those interfering with the aldosterone mechanism in the distal nephron, is hypokalaemia. Severe symptomatic hypokalaemia (serum K+ concentration less than 3.0 mmol/L) is rare except in clinical situations in which additional hypokalaemic factors are present. Moderate levels of hypokalaemia (serum K+ concentration 3.0 to 3.5 mmol/L) can increase the risk of adverse reactions as has been shown in a variety of prospective clinical studies. Hypokalaemia has effects on cardiac rhythm, muscle function and integrity, local blood flow, carbohydrate metabolism, and the blood lipid profile. Performance studies generally show diminished exercise tolerance in direct proportion to the degree of hypohydration induced. This is not the case, however, in a clinical setting of compromised cardiopulmonary function, in which diuresis has direct and indirect inotropic effects which augment exercise tolerance and decrease symptoms. The ability of the carbonic anhydrase inhibitor, acetazolamide, to induce a hyperventilatory response to the obligatory metabolic acidosis is taken advantage of in mountaineering to prevent or ameliorate the symptoms of acute mountain sickness, thereby improving exercise performance at high altitude. It is suggested that in clinical situations in which the use of a diuretic is considered appropriate, every effort be made to maintain or restore the serum concentration and the total body store of potassium to normal. To some degree this can be accomplished through diet, although potassium chloride supplements or potassium-sparing diuretics or diuretic combinations may be necessary.

Peak week recommendations for bodybuilders: an evidence based approach

“…Water and sodium are frequently manipulated by bodybuilders, either independently or concurrently, employing a variety of strategies involving “loading” and restricting both [ 11 ], with the goal of minimizing subcutaneous water to maximize the underlying skeletal muscle definition [ 8 , 11 , 12 , 14 , 19 , 20 ]. Bodybuilders have been reported to self-prescribe potentially dangerous pharmaceutical diuretics to facilitate the process [ 8 , 19 – 21 , 34 , 35 ]. Bodybuilders may also employ these strategies to drop down to lower weight classes, which can provide a competitive advantage if the competitor is able to regain some of weight in the form of intramyocellular volume (“filling out” via glycogen and/or intramyocellular triglyceride storage) prior to competition.…”

“…volume), (2) minimizing subcutaneous water (in an effort to look “dry” as opposed to “watery,” thus enhancing muscularity), and (3) minimizing abdominal bloating to maintain a smaller waistline and optimize physique proportion and overall aesthetics [ 11 , 12 , 14 – 17 ]. While competitors may use natural methods to achieve these goals, self-prescription of potentially hazardous drugs such as insulin and diuretics have been widely reported [ 8 , 18 – 21 ].…”

“…Although many peak week protocols exist that attempt to enhance aesthetics, research is lacking in regards to the efficacy and safety of the methods commonly used by bodybuilders. Among enhanced bodybuilders, the self-prescription of drugs such as insulin and diuretics have been reported with potentially dangerous outcomes [ 18 – 21 ]. The purpose of this article is to: (1) review the current literature as to the peaking protocols most commonly employed by bodybuilders; (2) provide evidence-based recommendations as to pre-contest peaking strategies for competitors and coaches.…”

The abuse of diuretics as performance‐enhancing drugs and masking agents in sport doping: pharmacology, toxicology and analysis

“…Even after rehydration, muscular endurance and performance are greatly compromised by diuretic use (Caldwell et al ., 1984). Additional studies performed on middle‐distance runners (Armstrong et al ., 1985) and wrestlers (Caldwell, 1987) confirmed that diuretics decrease the effects on overall athletic performance. Although insufficient data are available to establish the effect of long‐term diuretic treatment on exercise capacity, it has been clearly shown that both single dose and short‐term diuretic treatment adversely affect maximal exercise capacity and the duration of prolonged submaximal exercise (Fagard et al ., 1993).…”

Cardiovascular Considerations in Middle-Aged Athletes at Risk for Coronary Artery Disease

“…Effects of diuretics on exercise performance have not been studied extensively (4), but the common effect of hypohydration has been shown to adversely affect strength, power, and endurance (9).…”