In tonight's episode the five leaders return to the DCU School of Health and Human Performance to visit Professor Niall Moyna and re-take their fitness tests to see if the past eight weeks have had any effect.
According to the good professor, twenty-four-year-old Sean has gone from having the fitness of an eighty-year-old to being average for his age.
"Your average fitness the last day we measured you was that of an 80-year-old. In the last eight weeks you've increased your fitness by 33% - that puts you average for someone your age."
Working mum Marie Grace had a shocking 30% increase in her fitness levels while Yvonne found out she has fantastic increase of 15%. Prof Niall told Yvonne that she was "moving towards the average for your age."
As an amputee, Chris faced numerous hurdles by taking on the Operation Transformation challenge but his determined attitude meant he came out swinging. His fitness increased by 13% which left Prof Moyna very impressed:
"For an able bodied person to increase their fitness by 13% would be incredible. It can not have been easy for him but I've never seen a guy so driven and so motivated."
Maireád, the youngest leader of the series, also made great progress and now has made it to the average fitness for her age group.
Also on tonight's episode, we watch Operation Transformation's 5k run in the Phoenix Park from last Saturday. The event had a fantastic turnout of five thousand people including 2fm Breakfast Republic's Keith Walsh who DJ'd the event and Ray D'Arcy who is the Operation Transformation radio partner on RTÉ Radio 1.
Operation Transformation airs at 8.30pm tonight on RTÉ One and at 7pm and 8.30pm tomorrow night.
Want to read more of our Operation Transformation inspirational weight-loss stories, get behind-the-scenes info or healthy, recipe tips? Click here. Catch up on OT on the RTÉ Player here.