A high school reunion. An October wedding. A vow renewal ceremony.

These are some of the special occasions for which the 2018 Daily Herald Fittest Loser Challenge participants are preparing.

Of course, the Fittest Loser title -- which is also celebrating a milestone -- is at stake as well. This is the 10th year that the Daily Herald and Push Fitness have worked together on the Fittest Loser Competition.

While all the contestants have their eye on the prize, what they're most excited about is the opportunity to make permanent life-changing transformations from the inside out.

Contestants have already begun training at Push Fitness in Schaumburg -- aiming to get fit by the final weigh-in and finale event in May. The contestants will work with their trainers at Push twice per week. In addition, they will complete Saturday morning boot camps together, and follow eating plans tailored to their specific needs.

It can be a grueling 12 weeks, but the results are worth it.

Meet the five contestants vying to become the 2018 Fittest Loser.

Chad Lowry

Chad Lowry, 44, a manager of customer engagement from Mount Prospect, is training with Mick Viken for an occasion that's just around the corner.

In March, he's heading back to Akron, Ohio, to celebrate his 25th high school reunion.

"I didn't go to my last high school reunion because I was so overweight," said Lowry. "I didn't' want another reunion to pass me by."

Fittest Loser contestant Chad Lowry, left, and his trainer Mick Viken. Steve Lundy | Staff Photographer

Lowry is hoping to go from 245 pounds to 165 pounds. He said his focus is more on accomplishing his goal and developing habits that will allow him to keep the weight off in the future, than it is on winning the challenge.

Shelly Daley

Shelly Daley, 42, of Arlington Heights applied to be a contestant at the urging of her mother, who follows coverage of the challenge every year.

Daley hopes the challenge will get her out of a diet and exercise rut, as this is the third time she's working to lose a significant amount of weight. She's lost 95 pounds on her own before, but said she struggles with keeping weight off.

Fittest Loser contestant Shelly Daley, right, and her trainer Michelle Jeeninga. Steve Lundy | Staff Photographer

A mother of two, Daley is hoping for a third child. She said she knows that at her current weight of 280 pounds, the odds of in vitro fertilization being successful are slim and her pregnancy would be considered high risk.

She said it was difficult to become pregnant with her first two children and wants things to be different this time. She's also hoping to gain more energy to play with her 5-year-old daughter and 1-year old son.

"Right now, my daughter wants to play at the park and I don't; I want to sit on the bench," said Daley, who stays at home with her children. "I just want to feel happy, not embarrassed, and play with my kids."

She knows the challenge is only the beginning of her journey. In the end, she hopes to be down to 170 pounds.

Michelle Jeeninga is training Daley at Push Fitness. Daley is looking forward to the workouts and believes that the most challenging part of the competition will be following the new diet plan because she "likes to eat everything I shouldn't."

Cullen, Daley's husband, and her family will offer her plenty of support. She is determined to win the challenge and keep the weight off for the long-term.

"My mind is in it. I'm so motivated and mentally ready to make this lasting change," said Daley.

Kirsten Binder

Kirsten Binder, 43, of Schaumburg recently expanded her marketing and communications company, Noon Key Productions.

As a new business owner, Binder said she found herself in more public facing roles and as she saw photos of herself at networking events and business functions, she felt that who she was on the outside didn't align with who she is on the inside.

Fittest Loser contestant Kirsten Binder, right, and her trainer Steve Amsden. Steve Lundy | Staff Photographer

She's excited to take on the challenge and be a role model for a healthy lifestyle for her four daughters.

Binder said her family will be there to support her throughout. The Binders make it a priority to eat together every evening. Binder said her husband Tom doesn't want her to feel like the odd man out at the table, eating something different because she's following her specific nutrition plan. Instead, Tom and the girls will eat what she's having.

"It's going to change our household," Binder said.

Binder is excited to work with her personal trainer Steve Amsden and looks at the challenge as the first step to a lifetime of better health and fitness.

"This transformation is holistic. It's not just food and it's not just burpees. It's about creating a mindset that's more positive," said Binder.

Kim Rosewell

An October wedding date led Kim Rosewell, 30, an account manager from Roselle, to apply for the Fittest Loser Challenge.

This life-changing event, plus knowing that she and her fiancé are planning to start a family soon after their wedding, makes now the perfect time to develop new eating and exercise habits.

Fittest Loser contestant Kimberly Rosewell, left, and trainer Nicole Steinbach. Steve Lundy | Staff Photographer

Rosewell said she has a history of yo-yo dieting and hopes this competition will end that cycle for good.

"I want to feel my best for the wedding," said Rosewell, who will train under Nicole Steinbach and hopes to lose 50 pounds through the challenge.

Rosewell said she is most excited to work with a personal trainer, learn more about nutrition, and understand the different nutrients and their importance.

"If I won it would be awesome. It would help me stay motivated," said Rosewell.

Nicole Mueller

Nicole Mueller, 42, of Schaumburg is also focused on upcoming nuptials, but of a slightly different variety.

When Hurricane Wilma hit Florida in 2005, Mueller had to forgo experiencing her dream wedding in Clearwater. But this year, that's about to change.

Mueller, her husband Tim, and their kids are set to head to Clearwater this September for a vow renewal ceremony and the wedding day they never got to have.

Fittest Loser contestant Nicole Mueller, right, and her trainer Patrick Stille. Steve Lundy | Staff Photographer

Mueller wants to make permanent healthy lifestyle changes ahead of that special occasion.

"It would mean the world to me to win this competition," said Mueller, who has had two ACL replacements. "It would mean that I have learned enough to create that lifestyle change needed to make me healthier , happier and more able to be a better wife and mom to the people I love most."

Mueller will train under Patrick Stille.

This medical receptionist describes herself as very competitive and can't wait to take on the competition. She'll have the support of her husband, parents, siblings, friends, and an amazing group of co-workers who are covering her shift every Saturday so she can attend boot camp.

She's friends with two former contestants -- Cheryl Rawski (2014) and James DeBouver (2017) -- who both inspired her to apply to the challenge and are supporting her throughout her journey.