This article is part of our Injury Analysis series.
Adrian Peterson and Ezekiel Elliott
Hamstring injuries are some of the most commonly reported ailments in the NFL preseason with several notable players already managing injuries to the area. The hamstring muscle group is directly involved in motion at two joints, the hip and knee, and is a critical component of acceleration and deceleration. As a result, the violent start and stops that skill positions like running back, wide receiver and cornerbacks face leave the hamstring particularly vulnerable to strains. An intricate healing process that is easily disrupted only further complicates the injury.
The healing process for a muscle strain starts with the inflammatory phase. This initial phase is marked by swelling and the body's first clotting response. The next step, the proliferative phase, begins while the inflammatory phase is ongoing. The proliferative phase is where the real repair work to the muscle tissue is done. During this phase, specialized cells utilize protein fibers, like collagen and elastin, to fill in the gaps created when the muscle fibers tore. This results in scar tissue that will be further addressed in the final phase of healing, the remodeling phase.
During remodeling, collagen fibers within the newly developed scar tissue are continually broken down and reformed. The goal here is to increase the strength of the new tissue. Unfortunately this is a somewhat inefficient process as it is completed in a haphazard and random manner. This is where a good athletic trainer or physical therapist comes into play, as these professionals can
Adrian Peterson and Ezekiel Elliott
Hamstring injuries are some of the most commonly reported ailments in the NFL preseason with several notable players already managing injuries to the area. The hamstring muscle group is directly involved in motion at two joints, the hip and knee, and is a critical component of acceleration and deceleration. As a result, the violent start and stops that skill positions like running back, wide receiver and cornerbacks face leave the hamstring particularly vulnerable to strains. An intricate healing process that is easily disrupted only further complicates the injury.
The healing process for a muscle strain starts with the inflammatory phase. This initial phase is marked by swelling and the body's first clotting response. The next step, the proliferative phase, begins while the inflammatory phase is ongoing. The proliferative phase is where the real repair work to the muscle tissue is done. During this phase, specialized cells utilize protein fibers, like collagen and elastin, to fill in the gaps created when the muscle fibers tore. This results in scar tissue that will be further addressed in the final phase of healing, the remodeling phase.
During remodeling, collagen fibers within the newly developed scar tissue are continually broken down and reformed. The goal here is to increase the strength of the new tissue. Unfortunately this is a somewhat inefficient process as it is completed in a haphazard and random manner. This is where a good athletic trainer or physical therapist comes into play, as these professionals can add method to the madness by specifically loading the injured muscle during rehab. This strengthens the scar tissue and reduces the likelihood of reinjury.
Timing remains key, as a premature return to action can result in a breakdown of the newly formed muscle tissue. In cases where this occurs, the reset button on the entire recovery process is pressed and the inflammatory phase is once again initiated. Furthermore, other risk factors, both internal and external, can be linked to hamstring injuries including outside temperature, natural flexibility, and even field surface.
Considering the numerous moving pieces just detailed, it's not surprising to see teams like the Vikings and Cowboys take a cautious approach with their feature running backs. In Minnesota, Peterson has returned to practice after entering training camp with a previously existing hamstring injury. The problem appears to be healthy enough as the team is considering giving the former MVP his first preseason reps since 2011.
Dallas' first-round pick Elliott didn't play in the preseason opener over the weekend due to his hamstring issue, though he was seen participating in walkthroughs on Monday. Elliott is expected back Tuesday though don't be surprised if his workload is carefully monitored.
Turf Burns
Jamaal Charles: The Kansas City running back is expected to take a major step forward on Tuesday as he'll be removed from the PUP list and return to practice. Charles is working his way back from the second anterior cruciate ligament (ACL) tear of his professional career but is expected back for the start of the regular season. Fortunately, this somewhat earlier than expected return could mean we get a chance to see Charles in preseason action. It's not a necessity, but watching Charles in game-speed could help solidify his health and potential as an early round fantasy option.
Rob Gronkowski: The Patriots tight end left practice early on Monday with an undisclosed injury. In typical New England fashion, the team remains tight-lipped regarding specifics. It did hint it was minor but no further information was provided. Don't panic just yet and keep a close eye on Gronk's availability in practice during the coming days.
Jared Goff: Professional football is back in Los Angeles though the future of the Rams made an early exit from the team's first preseason game. Goff entered in the second quarter but lasted just two series following a hit from Dallas linebacker Derek Akunne. The issue is with his nonthrowing shoulder and is currently classified as soreness. Head coach Jeff Fisher downplayed the severity of the injury and this appears to be a case of L.A. taking a cautious approach with the future of its franchise. Goff returned to action Monday and remains a solid addition in keeper or dynasty leagues.
Greg Olsen: Olsen didn't practice Monday after experiencing back spasms. The situation isn't believed to be serious, but this is a good time to remind fantasy owners that spasms are not a true injury. Back spasms are often a symptom of an underlying issue, most commonly a muscle injury. Spasms can be a severely limiting and recurring condition that often fails to improve until the root of the problem is addressed. Carolina is confident its Pro Bowl tight end will be back in action soon but watch for more details to become available.
Thomas Rawls: The Seahawks running back was an active participant in practice Monday for the first time since undergoing surgery to repair a broken ankle. While Seattle will continue to monitor his workload to prevent any complications and other indirect injuries, his appearance is encouraging. Reports out of practice were even better as he looked "terrific" making cuts in traffic and showing signs of smooth acceleration. If he continues to progress, fantasy owners likely will get a chance to see Rawls in some preseason action. Given the complexity of the injury, I still think it's wise to invest in a reliable backup or handcuff Rawls to one of the other Seattle running backs.
Sterling Shepard: The Giants medical team appears to be taking the conservative approach with their rookie wide out. Shepard was removed from the team's preseason opener after reporting soreness in his groin but he did manage to practice a few days later. The team opted to follow that with an additional rest day to minimize his number of overall reps. Shepard has a real chance to line up opposite Odell Beckham this season, especially with veteran Victor Cruz already managing a groin injury of his own.
