“George Clinton and Parliament Funkadelic may perform for anything from 1.5 hours to 2.5 hours,” declares a notice from the venue, which proves a conservative prediction. Since giving up crack, George Clinton is rejuvenated. A few years ago, he could be on and off the stage – a peripheral figure in his own band. Here, wearing a suit and hat that makes him look like a psychedelic George Melly, the 73-year-old is involved in every single minute of a three-hour marathon.

He conducts the huge ensemble – one of his tightest – with the authority of a band leader, sings, gives trademark monologues (“Free your ass and your mind will follow…”), and leads the audience by waving his arms and, unfeasibly, jumping up and down. It’s a party-meets-aerobics-class hosted by a legend of the funk.

Although a new Parliament album is apparently on the way, the set – and rightly so – rattles through the catalogue that made his name. As soul, rock, funk and hip-hop are put through a psychedelic blender, the virtually continuous jam of songs still sounds futuristic.

There are elongated guitar solos, space odysseys, a topless man in furry trousers walking on his hands, and three fresh-faced, leather and leopard-print-clad female backing singers, the latest generation of the Brides of Funkenstein.

Classics pile up – a pulverising Give Up the Funk (Tear the Roof Off the Sucker), a sweet Atomic Dog and a unifying One Nation Under a Groove – and when the house lights go up, it seems it may take industrial machinery to get the band off stage. There’s a lovely moment when one of the co-singers asks, “Everybody give it up for Mr George Clinton,” and the entire room honours one of music’s great elder statesmen, who is right back on his game.

• At Birmingham Academy, 19 April. Box office: 0121-622 8250. Then touring until 24 April.