What is the Aluminium Curl Bar? The Aluminium Curl Bar is a high grade aluminium bar by Inspire Fitness that has been designed for use as a bicep isolation movement. By providing selective resistance to the bicep, the muscle is forced into a state of isolation which allows it to grow effectively. The Aluminium Curl Bar allows bodybuilders & fitness enthusiasts to achieve the recognisable & much sought after peak at the centre of the muscle which is best achieved using focused contractions which isolate the muscle & cause growth in a specific area.