In July, men’s national team midfielder Stuart Holden tore his right ACL during the Gold Cup final against Panama, renewing interest in PEP—a program that reduces the risk of knee injuries by strengthening core muscles.

We often think of ACL tears as fluke injuries, part of the dice roll that comes with playing in the NFL. As the narrative goes, the dreaded “pop” of the ruptured knee ligament afflicts elite athletes not for a lack of conditioning, but because it was simply time—a fait accompli that sends players like Eagles wideout Jeremy Maclin crumpling to the turf untouched during training camp. But Dr. Bert Mandelbaum, a surgeon from Santa Monica and a team physician with U.S. Soccer, says that’s not the case.

At least nine players tore an anterior cruciate ligament in either training camps or preseason games, including a second Eagle, linebacker Jason Phillips. In the first two weeks of the NFL season the Steelers’ Maurkice Pouncey and the Colts’ Vick Ballard suffered ACL tears. Mandelbaum, who has spent more than a decade developing a program for young athletes to avoid knee injuries, says many of those painful and costly injuries can be avoided by doing preventative exercise three times a week for 15 minutes. He started his research with female youth soccer players and recently performed a study of 60 men’s college soccer teams. He found that players who did the prescribed drills were 66% less likely to tear an ACL over the course of the season, and he believes those results can translate to the NFL.

Mandelbaum’s prevention routine—termed the PEP program—doesn’t focus on the knee but instead involves a combination of plyometrics, stretching and hip-strengthening exercises. “When we first looked at this thing, we found that the deficit was not in the knee. It was actually in the hip,” Mandelbaum says. “No matter the sport, the relative weakness and lack of control in the hip musculature was putting the knee in a bad position, loading the ACL, and then causing it to tear.”

Dr. James Andrews says Mandelbaum is on to something, though he isn’t sure to what degree Mandelbaum’s exercises might affect pro athletes. “As a consequence of ACL injuries, soon, prevention programs will become more sophisticated, especially for younger athletes,” Andrews says. “It is most effective for younger, developing players.”

Steelers center Maurkice Pouncey tore his right ACL and MCL in Week 1 against the Titans, ending his season.

In 2002, Ariko Iso became the NFL’s first female full-time athletic trainer and spent 10 years with the Steelers before joining Oregon State. She subscribes to the prevailing belief that NFL players already boast elite core strength, flexibility and body awareness, meaning ACL tears at that level are often fluke occurrences. But, she says, “That doesn’t mean they don’t need work in certain areas.”

Iso’s staff performs tests known as FMS—Functional Movement Systems—on Oregon State athletes to determine trouble spots. She agrees that core exercise can help reduce ACL injuries in collegians. Oklahoma football trainer Scott Anderson, the president of the College Athletic Trainers Society, says the Sooners have seen anecdotal evidence supporting the knee bracing of linemen and choosing the right shoe for the playing surface as ways to diminish risk of ACL tears. He believes core strength is a factor, but hasn’t looked for a causal link between it and ACL injuries.

Perhaps the largest obstacle for Mandelbaum’s program, however, is the individualist strength and conditioning culture of the NFL. Most clubs do not have extensive team-specified workout plans. Players arrive with their own regimens, often developed at college, and for the most part they stick to them. “Many athletes have their own routine coming from different colleges or working with a personal trainer,” Iso says. “They don’t really have a program the entire team does together.”

The obstacle for Mandelbaum’s program is the NFL's individualist strength and conditioning culture. Most clubs don't have extensive team-specified workout plans.

The same goes for U.S. Soccer’s various teams at the youth and senior levels. Coaches are largely unreceptive to Mandelbaum’s program until disaster strikes. In July, men’s national team midfielder Stuart Holden tore his right ACL during the Gold Cup final against Panama, renewing interest in PEP. But Mandelbaum anticipates that it will fade with time.

“Coaches get complacent because they’re not seeing a large number of ACL injuries,” he says. “Because of Stuart, everyone will call me and say we’ve got to have prevention programs. That will go on for a year or two, then everybody will get bored again, and we’ll go back to square one.”

Such a cycle prevents Mandelbaum from collecting conclusive data on adult athletes, leaving him with little ammo against those who believe pros can do little to prevent knee damage. He says there’s an educational hurdle to overcome: Strength and conditioning coaches are largely uneducated on the control points in the hip.

If anybody is going to break the mold, it could be the Eagles. First-year coach Chip Kelly has instituted a sports science program unprecedented in its comprehensiveness. And for motivation: He’s already lost two players—including a No. 1 wideout—to an ACL tear.

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