Entitled “Rods fitness routine, round 1″, the first clip shows the star on an exercise bike before he tackles a rowing machine and a treadmill for one minute bursts.

Sir Rod then shows off his weightlifting skills in another piece of footage, captioned “Round 2″.

But the Celtic fan admits weights are not his favourite thing and soon puts them down to dash out on to his football pitch, yelling “yay!” and immediately scoring a goal.

Model Penny, 46, shared another clip with her 31,300 followers on the social networking site, showing Sir Rod and one of his sons working out in a pool.

She wrote: “A normal pool workout to keep fit for life (heart monitor on)!

“Who’s keeping up with who! Not bad Sir Rod!”