MONTERREY – Dripping with sweat, the burly footballers sprint across the pitch seeking to score in Mexico's Heavyweight Football league, where points are awarded not just for goals but for shedding weight.
Mexico is the second-most obese country in the world, after its neighbor the United States. But in the northern city of Monterrey, the amateur Heavyweight league is using Mexicans' passion for football to fight the problem.
Co-founder Raul Pequeno says he got the idea while watching a professional football match on TV with his daughters a little over a year ago.
"We were watching the (Monterrey) Rayados and I started criticizing a player named Edwin Cardona, because he looked a little fat," said Pequeno, 35.
"One of my daughters said to me, 'You don't even play,'" recalled Pequeno, who weighed 157 kilos (nearly 350 pounds) at the time. Today, he weighs 143 kilos (315 pounds).
"She was completely right," he told AFP.
The conversation got him thinking, and soon he was organizing a tournament for other men his size. A women's tournament soon followed.
A children's tournament is next: Mexico has the dubious distinction of having the world's worst childhood obesity problem.
That first edition of the tournament drew just 14 players. Today, there are nearly 150.
The women's league drew some 50 players in its first year.
Before each match, players have to step on the scales to record their weight loss since the previous match.
Winning on the pitch earns two points in the league table. Winning on the scales earns three.
"You can win every match, but if you don't give it your all (to lose weight), you can still lose," said Pequeno.
The league has its own nutritionist, who crafts personalized meal plans for the players each week and helps them reach their goals.
"We basically put them on a diet that applies to the overweight and obese population in general, to give them a better quality of life," said Larissa Carbonero, the nutritionist who advises the women's league.
Players' banter is as much about diets as it is about football.
"You gotta drink more water!" one player goaded another after a recent match.
Other cities in Mexico are looking to create their own overweight leagues, inspired by success stories like Jose Vargas's.
Vargas decided to lose weight when his daughter was born.
He weighed 152 kilos when he entered the tournament. He has lost 20 thanks to football, and says he feels more agile.
"It's been great to kick the ball again, play matches, get up to speed, and little by little it also helps you lose weight," said Vargas, 36, sporting the jersey of Spanish club Real Sociedad.
"I was too overweight to play anywhere else. This is the perfect opportunity."