By: Jerry Palmieri and Darren Krein
Originally Published in: Strength Training for Football
Provided by: Human Kinetics
In football, athletes are divided into six positional groups: Offensive and defensive lineman; tight end, fullback, and linebacker; wide receiver and running back; defensive back; quarterback; and kicker and punter. Each faces different tactical and physical demands. The sample programs in the season-specific chapters in Part III are divided into these positional groups.
Understanding the positional demands and differences between groups is imperative given their implications in creating appropriate periodization strategies and programming options for athletes. An analysis of collegiate football athletes has shown that generally, non-linemen (e.g., wide receiver, defensive back, running back, quarterback) run more and wide receivers and defensive backs specifically cover greater total distances than any of the other positions on the field. While elements of individualization are often over-hyped in popular media, factors such as athlete load, distance covered, and readiness must be taken into account when designing resistance training programs, especially those that target the muscles of the lower body.
From a contact adaptation standpoint, an evaluation of impacts in collegiate football revealed that running backs and defensive tackles engaged in a larger number of severe and heavy collisions (defined as >10 g-forces) than other position groups. This lends further support to the fact that positional differences must be taken into consideration by strength and conditioning professionals. This research has its limitations because the position groups listed in the literature are often broad and will vary by offensive or defensive scheme, the athletes' level of gross and discrete motor skill competency, practice design, the instruments used to capture the data, roster size, time of year (e.g., training camp, preseason, in-season), and the age of the athletes and level of play (e.g., youth, collegiate, pro) Due to the recent emergence of more organized and refined GPS data collection within the sport, there is also limited quantification of all of the physical demands specific to each group. That being said, some brief points have been included here for quick reference that better clarify the key physiological characteristics for each position or group.
Offensive and Defense Linemen
Football games are often won or lost in the trenches; hence the need for strong, powerful, and quick offensive linemen. Offensive linemen will usually start plays in a crouched or squatting position. Due to the impact loads they must absorb and deliver, their need for maximal strength is often much greater than that of nearly any other position on the field. Unlike athletes at other positions, offensive linemen are constantly trying to move or to fend off opponents for the entire length of nearly every play. Offensive linemen must be highly conditioned to adapt to this type of contact. The biomechanics and postures required by the position, plus the fact that offensive linemen often fall or are fallen on by others, mean that offensive linemen and their strength and conditioning professionals must take special precautions to protect against knee, shoulder, hand, and ankle injuries, among others.
Defensive linemen are typically some of the largest athletes on the field. For the purposes of this book, it is not practical to give a range of ideal weights or heights - they will vary significantly from the Pop Warner level to the NFL, and they will differ according to the defensive scheme preferred by the head football coach. Typically, defensive linemen exhibit a more aggressive style of play than their offensive counterparts do, but both defensive linemen and offensive linemen collectively perform a larger number of movements that are highly specific to their positions (swim, rip, spin, rush, shuffle, kick-step, etc.) compared to positions such as running back or wide receiver. Defensive linemen may line up in varied positions (stand-up, three-point) based on the defensive package and their individual abilities. Due to their large body mass and the frequency and nature of their collisions with others, interior linemen especially are at risk for knee and ankle injuries, so they must pay careful attention to lower body resistance training and mobility strategies.
Tight Ends, Fullbacks, and Linebackers
In what is one of the most unique of the positions, tight ends may serve as additional linemen or run blockers on some plays, while they may serve as additional receivers on others. They do more sprinting than both offensive linemen and defensive linemen but typically less than running backs, defensive backs, and wide receivers. Tight ends must be strong and durable in order to take on opposing linebackers, linemen, and even defensive backs blitzing at maximal speed. They must also possess the grace, timing, hand-eye coordination, and precision of a wide receiver.
Once a trademark role for hard-hitting, power-based offenses at every level, the fullback position is now less common in modern football, or the role has become more diverse. While fullbacks are primarily expected to block or clear the way during both running and passing plays, it is not uncommon for them to serve as auxiliary receiving targets. Fullbacks usually have a short, wide stature (i.e., a low center of gravity), which is a tremendous benefit for blocking or running through would-be defenders. Fullbacks will not make contact with an opposing athlete as often as an offensive lineman or defensive lineman will, but they do so far more than running backs and wide receivers. The collision and locomotive loads imparted on them are more similar to those of a linebacker or a tight end. Fullbacks are often some of the strongest athletes on the team in their lower bodies, and although they do not stand out in terms of absolute speed (30-yard [27-m] sprints and beyond), their high levels of lower body strength and force production are evident when they accelerate or explode through a pack of defenders.
Often referred to as the quarterbacks of the defense, linebackers can be some of the most exciting athletes to both watch and train. The position is highly physical, with impact forces often surpassing even those of offensive and defensive linemen, but it also requires the speed and finesse needed to drop back into pass coverage or pick up a wide receiver coming across the middle. Like their defensive back counterparts, linebackers will call upon a wide movement cache, including linear and lateral sprinting, shuffling, crossover running, backpedaling, and jumping. Linebackers will also typically do more high-speed sprinting than defensive linemen, but not as much as defensive backs.
Wide Receivers and Running Backs
Wide receivers and defensive backs often face the highest amount of athlete load of any position in football (28). The combination of high-speed linear sprinting, variable cutting maneuvers during route running, and blocking responsibilities over the course of not only weekly practice but also competitive games can quickly take a toll on the calves, ankles, Achilles tendons, and hamstrings of the wide receiver. Special care must be taken by the strength and conditioning professional to ensure that high-volume resistance training for the lower body is reduced during times in which athlete load is highest. This is, of course, true across all positions, but aside from defensive back, few positions are exposed to the same volume of specialized workloads as wide receiver. The best way to foster an adaptive and resilient stimulus is to repeatedly expose it to stress. In the case of the wide receiver, this means athletes must not only develop adequate strength qualities (especially those of an eccentric nature, which are inherently protective), but they must also be exposed to higher-velocity movements in the weight room that target the posterior chain, such as the two-arm kettlebell swing, various weightlifting exercise derivatives, and even ballistic exercises such as medicine ball tosses and throws.
Running backs are some of the most elusive and explosive athletes on the football field. Although their involvement and total high-speed running distance and athlete load will vary tremendously based upon scheme, running backs must have significant levels of lower body strength in order to run through tackles and maintain a solid athletic base and a lower center of gravity when blocking opposing defenders. They also must have great vision and catching ability because they are often called upon to catch screen passes out of the backfield and other short passes in order to misdirect the defense. Compared to their offensive teammates, running backs will traditionally cover more cumulative sprint distances than offensive linemen, fullbacks, tight ends, and quarterbacks but fewer than wide receivers (depending on offensive system). Like defensive backs and fullbacks, running backs are subject to higher-velocity impact forces, which may increase the risk of injury from concussion, ACL tear, shoulder separation, and the like. Thus, durability and strength and power qualities must be emphasized throughout the physical preparation process.
Due to not only the demands of the sport, but also the unique roles assigned to their position, defensive backs are often required to use multivariate modes of locomotion, including back-pedaling, shuffling, drop-step and open-step techniques, linear (straight-line) running, and crossover running. When pursuing a wide receiver in coverage, or when trying to knock down or intercept a ball that has been thrown, a defensive back may open or drop back at 45-, 90-, or even 180-degree angles. Even when performed at submaximal speeds, this requires tremendous proprioception, mobility, visual acuity, and timing. Additionally, although no current research has directly compared backpedaling and crossover running, there is research that has examined general forms of lateral, backward, and forward locomotion. This has shown that during linear running, propulsive forces are generated by the hip extensor muscles (gluteus maximus and hamstring group), the knee extensors, and to a lesser degree the plantar flexors, whereas during backward running, most of the propulsive forces are driven by knee extensors and hip flexors. Along with wide receivers and running backs, defensive backs typically cover some of the greatest total distances on the field (if not the greatest total running volume), and although they do not have to withstand the same frequency of collisions that offensive linemen, defensive linemen, tight ends, and linebackers do, the impact forces they do experience are often much higher due to their velocity at the time of impact.
Over the years, few positions have evolved as much as the quarterback position. Body types of quarterbacks can vary broadly, and one should not expect the same physical attributes for a quarterback in a pro-style offense that would be found in one who leads a triple-option attack. This holds true regardless of whether one is analyzing the NFL or the collegiate level. In one week a defense may have to prepare for the likes of a true dual threat such as Cam Newton, and in the next week they may need to adjust to a more traditional pocket passer such as Matt Ryan. Even when these athletes retire, the archetypes (dual threat and pocket passer) will still exist, as they have for well over 40 years. Quarterbacks of all types must have upper body strength, shoulder mobility and stability, trunk stability, and lower body strength and mobility. All of these collectively help to both produce and transfer force through the kinetic chain. These physical qualities are crucial for all positions in football because the sport calls upon the entire system to function well in order to maximize both performance and resilience.
Kickers and Punters
While often overlooked and underappreciated, quality special teams play is a critical contributor to team success. Kickers and punters alike are expected to jump into action during some of the most stressful situations, and they must be able to focus under tremendous pressure and deliver with preternatural accuracy, timing, and precision. Due to the unilaterally dominant nature of the position, strength and conditioning professionals must place a premium on addressing and improving the mobility and stability of not only the kicking leg but also the stance leg. Some strength, power, and mobility asymmetries will exist between the stance leg and the kicking leg due to the frequency with which the activity is performed (which affects such things as motor learning, rate coding, and force production), but coaches should aim to manage those asymmetries as much as possible through the regular inclusion of both single-leg hip- and quad-dominant exercises (e.g., split-squat and lunge variations, single-leg Romanian deadlift variations, bridging and leg curl variations, and mini-band walks) as well as single-leg power movements (hops to a box, over hurdles, etc.). Furthermore, stability and proprioception can be improved through the inclusion of exercises and drills where the athlete drops off a box and lands softly on one foot, or even performs a level change by dropping from two feet to one foot. All of these exercises should be performed under varying conditions (e.g., strength and plyometric exercises performed in frontal, sagittal, and transverse planes), to ensure the well-rounded development of multiple qualities.
Due to the popularity of football, the media coverage it draws, and the training protocols of many of the athletes who compete at the highest level (many of whom become celebrities), countless myths have arisen about the best way to train. Most of these practices are not based on scientific evidence. More often they serve as eye candy or as ways to sell expensive training equipment, not as ways to do the simple things savagely well. The information presented here should serve as a solid starting point for both further reflection and investigation into the physiological and positional demands on football athletes, and it will complement the training regimens prescribed in other chapters of this text.
Neither performance enhancement nor the art of coaching in general are topics that can fit into a vacuum. Just as football athletes must call upon a wide variety of movement skills in order to succeed, strength and conditioning professionals must use a wide array of strategic plans, evidenced-based approaches, assessments, and even, at times, improvisations to ensure that none of the physical capacities and complex motor skills that produce explosive multiplanar movement are neglected. To date, no long-term, peer-reviewed scientific data exist to show a definitive relationship between a team's resistance training program and its win - loss record. Nevertheless, strength and conditioning professionals have a responsibility to their athletes not only to develop the technical aspects of their movement, but also to educate their athletes about why achieving certain biomechanical positions can both enhance performance and prevent injuries. The collective aim should be to help athletes to have long and productive careers, and this can be done by developing a strategic framework to help guide programming decisions.