From left: Jim Bob Duggar, former NFL player and trainer Steve Conley and Josh Duggar
Courtesy of Duggar Family
03/12/2013 AT 01:30 PM EDT
The Duggar clan is shrinking – by over 50 pounds.
Jim Bob Duggar, 47, and his oldest son Josh, 25, of TLC's 19 Kids & Counting
airing on Tuesday nights at 9, are in a fierce weight-loss challenge with each other.
"I got back from Asia and looked at myself on camera and realized something had to change," says Josh.
Married to Anna, 24, and looking forward to the addition of the couple's third child
this summer, Josh says he was at 238 lbs. and not feeling healthy. In October, he started to cut back and make healthier choices – and began to see the weight drop.
"I have learned not to grab that bag of potato chips or all that stuff full of sugar," says Josh, who last weighed in at 202 lbs.
Meanwhile, his father, Jim Bob, was starting to feel a little pudgy himself, he says, after his wife, Michelle, 46, started to leave him in the dust when they were out together.
"A few years ago, Michelle had put on some weight and her back was hurting, and the doctor said that if she walked every day and lost some weight she would feel better," he says. "She lost 40 pounds, did Weight Watchers and learned how to eat healthy and exercise. Then she started doing the elliptical, and she almost can run off and leave me. I could hardly keep up with her."
The busy father of 19 blames poor eating habits for his hitting 220 lbs., and says, "I wasn't feeling that great."
He and Josh discussed a weight challenge and both began eating healthier and working out. Jim Bob's third son, Joseph, 18, initially set up a workout plan for the pair. To make the contest more interesting, they've agreed that on April 1 whoever has lost the most weight will be waited on – think breakfast in bed – by the other. Right now, Jim Bob says he's about 199 lbs.
"There are so many benefits to getting in shape and losing 10 percent of your body fat. It just makes you feel better," he says. "I feel like I'm thinking clearer, it is easier to get up out of a chair."
In addition to cutting out on fried food and sugary food and replacing daily sodas with water, he's been building up to at least three miles per day on the elliptical, sometimes going as many as seven miles.
Both Jim Bob and Josh are both working with former NFL Pittsburg Steelers linebacker Steve Conley, who is now a personal trainer.
Josh says that getting fit is good for his whole family.
"My daughter [Mackynzie] didn't tell me I was fat," he says. "But now she thinks I have strong muscles. I know I need to set an example of being healthy for my children."
And as far as the competition goes, both are determined to be victorious.
"The competition is working out perfectly," says Josh. "Maybe it will inspire others."