IRVINE, Calif. -- By the end of the season Brandin Cooks will be drooling for a burger.

And that’s a long time when you’re eating nothing but greens, beans and the occasional lean white meat and fish.

Vegetarians (a person who doesn’t eat any meat) are rare in the NFL, according to Los Angeles Rams dietitian Joey Blake, because of the grueling nature of the season and a player’s need to maintain their weight. Some, however, like Rams receivers Brandin Cooks and Cooper Kupp, are trying to eliminate as much meat as possible from their diet.

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For Cooks, it’s a diet that has evolved over several years. He has found the foods to get him through a 17-week schedule, plus training camp and playoffs, and allow for expedited recovery after practices and games.

“It’s just getting to know my body and what foods it likes,” Cooks said. “What food that it takes a tougher time to break down.”

Kupp, a rookie last season, grew perplexed as the season wore on as he continually got questions about the so-called rookie wall. That never happened after he implemented a diet in which fish is the only animal-based protein.

“It’s something that I’m working on,” Kupp said. “But I felt good doing it, just in terms of anti-inflammatory stuff. I wanted to kind of help myself in terms of recovery.”

Blake calls Cooks and Kupp “hybrid versions” of different diets. Pescatarians (those whose only meat is fish) and flexitarians (those who eat less meat or try to avoid other animal products) are popular terms all over the food world. Both Kupp and Cooks have eliminated red meat and strictly limit other meats from their intake.

“For the most part I am vegan [a person who does not eat any animal products],” Cooks said. “Definitely no egg or dairy for me, just because my body, it has a sensitivity to that. Not necessarily allergic, but just want to be able to take as much as I can and keep the inflammation down internally.”

The challenge becomes fueling a player who engages in rigorous daily activity and burns endless amounts of calories like NFL receivers.

“The biggest issue is not getting enough protein and from that standpoint, getting high-quality protein,” Blake said, adding that there is no one-size fits all method when it comes to determining how many calories and how much protein an individual needs. “That can vary so much and it’s all what your metabolism is like and what your body is like.”

For Kupp, it was his wife Anna, a former collegiate athlete, who first turned him on to clean eating. She would cook dinner and make a meat-filled side dish for Kupp. Eventually, she only had to focus on the main course as Kupp eliminated meat and turned pescatarian, discovering an improved feeling throughout his body.

“It comes down to inflammation and how do you keep the inflammation down during the season,” Kupp said. “You can gain back a day just based on getting your body recovered and getting inflammation down so you can go back out there and compete and work. That can be a huge advantage based on what you’re eating.”

Blake said the Omega 3 fatty acid found in fish was key in Kupp’s ability to recover after enduring the physicality of games.

“With that fish, it’s really manageable high antioxidant content,” Blake said.

Brandin Cooks tries to avoid dairy and drinks a lot of vegan protein shakes. Kirby Lee/USA TODAY Sports

At 6-foot-2 and 205, Kupp said the biggest challenge was not keeping the meal interesting -- it's a rotation that also includes a lot of beans, quinoa and pasta -- but keeping his weight up, staying hydrated and maintaining enough calories to burn.

“You’ve got to be constantly refueling,” Kupp said. “In the morning, it’s fueling for the day. At night, it’s fueling for the next day. It’s a constant, never-ending deal.”

Cooks, on the other hand, always had an interest in his diet, but said he was inspired to take it to the next level by former teammate Tim Hightower with the New Orleans Saints and Tom Brady with the New England Patriots. Cooks’ does not follow Brady’s famous TB12 Method -- no avocado ice cream yet -- but he has molded a diet to fit his needs.

“It’s a huge difference on how I’m recovering, how I’m sleeping and just my energy and my fuel source,” Cooks said.

So what does the 5-foot-10, 189-pound Cooks actually eat?

Gluten-free, non-egg pasta and marinara sauce. Quinoa, brown rice and beans, sometimes with pieces of grilled chicken. Kale and spinach. And his go-to vegan protein shake.

All the time.

The diet can become repetitive, Cooks said. But in order to maintain his weight, he has to continue eating.

“Definitely my portion sizes are a lot bigger than they were before to be able to get to that full feeling,” Cooks said. “So it’s definitely a challenge because I’ve got to eat a lot more and I’m not the type of person that actually likes to sit there and eat.”