Final answer:
Clenbuterol use by athletes can cause cardiac arrhythmias as one of the side effects.
Step-by-step explanation:
The use of Clenbuterol by athletes can cause cardiac arrhythmias as one of the side effects. Clenbuterol is a beta-agonist that is commonly used as a bronchodilator and for its thermogenic (fat-burning) properties. However, it can also stimulate the heart and cause irregular heartbeats known as cardiac arrhythmias.