Frew, from Grangemouth, featured on tonight's edition of the popular programme Ninja Warrior UK which aired on ITV at 7pm.
Contestants are challenged with completing a obstacle course in the fastest time possible with the top ten qualifying for the semi-finals.
Frew, who turns 44 on February 6, was the final contender shown in the episode and, although he finished the course with relative ease, there was a nail-biting moment at the end when he forgot to press a button to clock his time.
He eventually realised his mistake quickly enough to qualify in ninth position.
Frew represented Scotland and Great Britain over 100 times at various international gymnastics competitions.
But the highlight of his career undoubtedly came in the 2002 Commonwealth Games - the fourth of five he competed in - when he took gold in the men's rings at the Manchester event.
It was the first time Scotland had landed a such a medal in gymnastics in the history of the Games.