All you need is a pair of sneakers! Twelve overweight people set off on the walk of a lifetime! It's an epic, life-changing journey that begins at the starting line for the Boston Marathon and ends in Washington, DC. The contestants and their two charismatic fitness trainers, Steve Pfiester and Lorrie Henry, will walk over 570 miles, passing through nine states, with the goal of shedding unwanted pounds and getting fit along the way in an attempt to permanently alter their lives. In addition, they all will compete for a prize pool of $1.2 million. Stressing team work, the more people who finish, the more money each person wins, on Fat March, premiering TUESDAY, AUGUST 7 (9:00-10:00 p.m., ET), on the ABC Television Network.

During each leg of the excursion there are "luxury reward challenges" where an individual or team can win incentives such as spa treatments, low calorie gourmet meals prepared by a private chef or deluxe accommodations for the night to help them on their trip. There are also amazing prizes at stake, such as get-aways to Hawaii and Las Vegas. The challenges are geographically specific to the area contestants are in. At the elimination, participants are able to expel a group member who is holding them back from reaching the finish line in the allotted time. However, eliminating a fellow competitor has a price: $10,000 is deducted from each competitor's potential prize money with each elimination.

As for their diet during the trip, the contestants eat five small meals each day, a combination of all natural whole grains, lean poultry, fresh vegetables and fruits.

In the premiere, "Episode 101," a huge surprise awaits the 12 contestants when they learn they will not be living in a mansion to lose the weight, but will be expected to walk over 570 miles to melt off the pounds, camping along the way. The march begins at the starting line of the Boston Marathon, where contestants walk alongside America's fittest athletes. During the first stage of the journey, they will take on their first exercise-based challenge in Massachusetts, harvesting cranberries in a flooded bog. The luxury prize for this test is a gourmet healthy meal and a night's stay at a luxe cranberry-themed bed and breakfast. Along the way, as they also hike through Rhode Island and Connecticut, one contestant, suffers a medical emergency and another has an emotional meltdown. Each competitor suffers through uncomfortable soreness and a fight against the elements that take significant wear and tear on their bodies.

Following are the 12 contestants walking through city streets and the countryside, completing special challenges along the way.

The six female competitors are:

Chantal, 35, 5'2", 250 pounds, comedian -- A student who resides in Brookline, Massachusetts. She dreams of one day owning a pair of slim designer jeans.

Jami Lyn, 30, 5'9", 226 pounds, military wife -- A housewife who resides in Daleville, Alabama. She is the mother of three children and finds it difficult to be so much larger than her husband and the only big person in the family.

Kimberly, 39, 5'5", 225 pounds, former rap diva -- A real estate investor who resides in Duluth, Georgia. She was once known as the rap artist Tempest with a top 20 album in Europe; her mother and father died four months apart due to weight-related issues when Kim was only 15.

Loralie, 30, 5'3", 233 pounds, wants to have a baby -- A marketing resources expert who resides in Milwaukee, Wisconsin. She's married and dreams of starting a big family, but her doctor demands that she lose weight first before having children.

Shea, 27, 5'7", 280 pounds, former college softball player -- A makeup/special effects artist who resides in Indian Rocks Beach, Florida. She is embarrassed that she is the biggest person in the makeup trailer, and her parents are worried about how her weight is affecting her health.

Wendy, 40, 5'6", 234 pounds, professional singer -- A bookkeeper who resides in La Canada, California. She is married with a six-year-old step-daughter and wants to return to the stage as a singer and songwriter, but needs to lose weight first.

The six male competitors are:

Anthony, 25, 6'3", 410 pounds, 25-year-old virgin - He is unemployed and resides in Addison, Illinois. He is determined not to let his being overweight kill him.

Matt, 36, 6'3", 386 pounds, professional wrestler -- He resides in Cincinnati, Ohio and is married with two children. He was released from pro wrestling in the U.S. last year when officials felt he was too heavy and it wasn't safe for him to compete. He must lose weight to return to his career.

Michael, 41, 6'2 &#189", 330 pounds, baseball coach - A lab technician who resides in Elwood, Illinois. He is married with two children and has tried every diet from A to Z.

Sam, 22, 5'9", 371 pounds, certified massage therapist - He resides in Everett, Massachusetts, is single, and believes that his weight has kept him from being hired.

Shane, 34, 6'0", 500 pounds, new dad - A youth minister who lives in Mesquite, Texas. He is married with a two-year-old child and another due in October, but wants to be around to watch them grow up.

Will, 26, 6'2", 470 pounds, competitive eater -- He works in retail and resides in Brooklyn, New York. He is single with no children and would like to inspire others to lose weight and get in shape.