Is Chris Martin the hardest-working Brit in show business?

There the singer was, Saturday night at Mohegan Sun, breaking a sweat literally after the first song of Coldplay's concert. He didn't just play guitar. He hopped and sprang while he did, doubling over or throwing his head back. When he took to the piano for songs like "Paradise," he didn't merely tap the keys. He thumped them, and he bounced on the stool. He bounded down the stage runway with his so-unhip-they're-hip dance moves and then dropped to his knees and bent backwards like a latter-day Springsteen.

He made sure to play to every part of the arena — scampering up to the top tier to perform a couple of songs, taking a few tours around the ramp behind the stage to give audience members back there their due.

If that makes him sound manic, he wasn't. He was just a really effective frontman.

If Martin was a rock 'n' roll dervish, the concert as a whole was just as spirited and entertaining. The band was tight, with drummer Will Champion in particularly vigorous form. Coldplay's songs, when played live, crackled with more vitality than they do in their recorded versions.

One segment did bog down, with a trio of underwhelming songs — "Princess of China," with Martin dueting with a videotaped Rihanna, "Up in Flames" and "Warning Sign." The band, though, immediately bounced back with "Don't Let It Break Your Heart" and the always wonderful "Viva La Vida."

And, oh, the cool stagecraft on display! When concert-goers entered, they were each given wristbands that lit up and flashed at various points in the show, making it look as if the auditorium suddenly filled with vibrantly colored fireflies. Cannons showered the audience with a snowfall of confetti during "In My Place" — the second song of the night. Hey, why wait for the finale to shoot off the cannons? For the remainder of the evening, the confetti littered the stage runway like rose pedals scattered down a wedding aisle.

Neon-shaded graffiti covered some of the set and even some of the instruments. Lights, naturally, zapped and glowed.

All that visual extravagance could have overwhelmed the music or seemed like shtick, but it worked.

Coldplay found a fab opening act in Naturally 7. The seven guys created all the sounds with their voices — no instruments, although you'd be hard-pressed to tell based on the full-bodied songs they produced. Hearing a performer create the equivalent of a drum solo using just percussive vocals was pretty astounding.

k.dorsey@theday.com