Madonna and Guy Ritchie's marriage broke down because the singer's muscular physique repulsed her husband, according to the latest reports.

Madonna is said to have restricted her days to long and enduring work outs to maintain her impressive biceps.

And, according to a UK publication, Guy told close pals that making love to Madonna was like 'cuddling up to a piece of gristle'.

A close friend told the News of the World: “When the cracks began to show in their marriage, Madonna wouldn't budge.

“Guy was pleading with her to spend more time with him but she wouldn't have it. She'd insist she did her four-hour workout and that would be half the day gone.”

Guy reportedly found this a turn off

The source added, “They've been apart so much in the last two years the times when they could have made love have been pretty limited.

“And they've been in separate bedrooms a lot after rows so there has been no making-up. They might as well be brother and sister.”

See Madonna's ever-expanding muscles here