Purpose: The ergogenic effect of acute beta 2-adrenergic agonist administra
tion in nonasthmatic individuals has not been clearly demonstrated Therefor
e, the acute effects of oral administration of the beta 2-adrenergic agonis
t salbutamol (4 mg) on muscle strength and endurance performance were studi
ed in 16 nonasthmatic men in a double-blind randomized cross-over study. Me
thods: Peak expiratory flow (Mini Wright Peakflowmeter), isokinetic strengt
h of the knee extensors and knee flexors at four angular velocities (Cybex
II dynamometer), and endurance performance in a cycle ergometer test until
exhaustion at 70% of maximal workload were measured. Results: Peak expirato
ry flow increased from 601 +/- 67 L.min(-1) to 629 +/- 64 L.min(-1) after s
albutamol (P < 0.05). Peak torque was higher after salbutamol than after pl
acebo (4.4% for the knee extensors, 4.9% for the knee flexors) (P < 0.05).
Mean endurance time increased from 3039 +/- 1031 s after placebo to 3439 +/
- 1287 s after salbutamol (P = 0.19). When four subjects complaining about
adverse side effects were excluded from the analysis, the increase in endur
ance time (729 +/- 1007 s or 29%) was statistically significant (P < 0.05).
Salbutamol did not affect (V)over dotO(2), respiratory exchange ratio, hea
rt rate, and plasma free fatty acid and glycerol concentration during exerc
ise; plasma lactate and potassium concentrations were increased (P < 0.05).
Conclusions: Under the conditions of this study, oral salbutamol appears t
o be an effective ergogenic aid in nonasthmatic individuals not experiencin
g adverse side effects.