Kings Of Leon frontman Caleb Followill has sparked rumours he has steroid injections to boost his voice.

The rocker insists life on the road with the Sex on Fire hitmakers is starting to take its toll after they resumed touring in May (13), and he has now detailed the steps he takes to ensure the show must go on.

Followill admits he regularly boozes before hitting the stage to give his performance an edge, and has even hinted he receives regular muscle-boosting steroid shots to strengthen his vocal cords.

He tells Q magazine, "When you're going as fast as we were going, or working as hard as we were, you get into a rhythm. Then it becomes a case of, well, if I'm gonna go out there and kick a** tonight then I need to grab a couple of drinks first. And I'm going to need a steroid shot just to sing. After a while, that gets on top of you."