Analyzing Hair Pulling in Athletics

Authors: Laura Ruhala, Richard Ruhala, Emerald Alexis, E. Scott Martin

Corresponding Author:
Laura Ruhala, Ph.D.
Department of Mechanical Engineering
Kennesaw State University
1100 S. Marietta Pkwy
Marietta, GA 30060
lruhala@kennesaw.edu
812-589-2982

Dr. Laura Ruhala is an Associate Professor of Mechanical Engineering at Kennesaw State University. Her research topics include biomechanics and engineering pedagogical techniques. She is an active member of the American Society of Mechanical Engineers and the American Society for Engineering Education. She enjoys collaborating with her husband and colleague, Dr. Richard Ruhala.

Analyzing Hair Pulling in Athletics

ABSTRACT
This paper investigates biomechanical and ethical issues surrounding long hair in athletics, with a focus on the population of athletes in the National Football League (NFL), the professional organization for American football, who is most affected. Background on the NFL rules regarding player hair length is described. Unlike grabbing a player’s facemask, it is not a penalty to grab and pull hair under certain situations in the NFL. The 2,905 players listed on rosters as of June 2015, are analyzed by their age, NFL units, positions, hair length, and style. Trends in player hair length are illustrated, and it is found that nearly ¾ of players with long hair, defined as long enough to reach their jersey, wear them in a dreadlock style. Three documented case studies of extreme hair pulling incidents by tackling in the NFL are described. A case study of hair tackling in women’s college soccer is also described. An engineering analysis is conducted to estimate the amount of force applied to a player’s hair during an actual NFL hair tackle. The forces are a function of the angle at which the hair is grabbed, and at some angles, the impulsive force applied to a player’s head and neck may exceed 500 pounds. Finally, the ethics behind hair tackles are investigated: both looking at the responsibility of the NFL for its players, as well as player sportsmanship.

Keywords: hair pulling, player injury, biomechanics, sports ethics, sportsmanship

INTRODUCTION
Athletes who choose to wear long hair while playing American style football are now a common site in Friday night high school games, as well as on televised college and professional games. For the purpose of this study, “long” hair is defined as being of at least shoulder length.
In high school football, tackling a player with his hair is penalized. Bob Colgate, the Director of Sports and Sports Medicine at the National Federation of State High School Associations, described these penalties related to hair-tackling (3). Most common are rules 2-16-2c and 9-5-1, which identify hair tackles as flagrant fouls and unsportsmanlike conduct. Philip Young, the Head Football Athletic Trainer at Kennesaw State University states that in college football, players are permitted to wear long hair, but the team coaches may ban it or specify that it be tied up in some way (57). In professional American football, the National Football League (NFL) allows players to wear their hair long. In addition, the professional football player in the NFL may be tackled by his hair (46).

Since the NFL has the fewest number of athletes along with team websites listing player names and current photographs, we selected the NFL for statistical inspection. This paper investigates the demographics of the players affected, introduces case studies of hair tackles, conducts and engineering analysis of a hair tackle, and considers the ethical implications of hair tackles. Additionally, the work is expanded to discuss a hair-pulling incident in women’s collegiate soccer.

Background on the National Football League
The NFL is a professional American football league consisting of 32 teams. There are 16 teams in the American football conference (AFC) and 16 teams in the National football conference (NFC) (8, 11). Each conference is then divided into North, South, East and West regions, consisting of four teams per region, as shown in Tables 1 and 2. Each team is required to have a minimum of four pre-season games. The regular season is 17 weeks long, beginning the week after the American Labor Day and concluding the week after Christmas. During the regular season each team plays 16 games. The postseason then commences in a 12 team, single elimination tournament. The AFC champion and NFC champion then compete in the highly prestigious Super Bowl (7).
Each football team is divided into two main units: offense and defense, with special teams making up a third unit (9). Each team can have 11 players on the field during any play. The specific role that a player takes on the field is called his “position”. A typical player lineup, showing player positions, is shown in Figure 1 for offense and defense, where X’s indicate defensive positions and O’s indicates offensive positions. Player positions and their acronyms are also indicated in Figure 1.

The special teams unit is on the field during kicking plays (1, 56). While many players play on offence or defense in addition to special teams, there are some dedicated special teams positions, including kicker, holder, long snapper and punter.

There are two different types of legal contacts between players: tackles and blocks, and only the player with the football in his hands is eligible to be tackled by the opposing players (10). The NFL defines a tackle as a statistic recorded when a defensive player makes contact with an offensive ball carrier, forcing him to go to the ground. The referee will blow their whistle, signaling a tackle and dead ball when the ball carrier’s knee, elbow, or buttocks makes contact with the ground, or when a player crosses the boundary line of the field. This can be done by pushing, pulling or by many other means. The styles used can differ wildly depending on the size and strength of the player, but most techniques involve attempting to wrap up a player’s body or legs to restrict their movement and force them to the ground. Helmet-to-helmet contact and/or pulling a player’s facemask are illegal, and will both draw penalties that are strictly enforced. Good tacklers try to keep offensive players from gaining any more yards after their initial contact. A tackle by grabbing the ball carrier’s hair, is permitted in the NFL. This rule is explained in the section below.

The NFL and hair length
Rules regarding hair length
Prior to 2003, the NFL did not have any rules regarding player hair length; some players had long hair, and there were no rules regulating tackles or blocks involving hair pulling. In 2003, the NFL addressed players being tackled by their hair after Dolphins running back Ricky Williams was dragged down twice in one game by the dreadlocks in his long hair. This so-called “Ricky Rule” declared a player’s hair to be an extension of his uniform; hence a player can be tackled by their hair, just as they can be by their uniform (46), and Uniform Rules apply. This means that when making a tackle, the defensive player can grab his opponent’s jersey – or hair – in an attempt to stop his forward motion.

Since the Ricky Rule states that a player’s hair is part of his uniform, and Uniform Rules apply, it is important to understand the rules regarding blocking or tackling via a player’s uniform, which vary greatly. When blocking, if a player makes excessive contact with the opposing player’s uniform, the player will be accessed a penalty for holding (10). A blocking penalty consists of a loss of 10 yards and the repeat of the down. Defensive holding brings with it a 5-yard penalty and a first down for the offense. Tackling a player by using his uniform is legal as long as the player does not hold on to, or make excessive contact with, the opposing player’s uniform or helmet after the play is whistled dead by the referee. If excessive use of contact is penalized, it will result in a 15-yard personal-foul penalty. Ultimately, the use of penalties is determined by the referee staff, and is oftentimes later debated by both the teams and the viewers.

Therefore, the Ricky Rule allows tackling using a player’s hair, but does not allow blocking using the hair. Incidental contact with a player’s hair may occur during blocking, but if the referees see it, a player will be penalized. Additionally if a player while tackling continues to hold and pull the hair of the ball carrier after the play is whistled dead by the referee, they will be penalized with a personal foul. In 2008, NFL owners considered but then ultimately tabled a rule that would have disallowed hair to cover the name on a player’s jersey (54).

METHODOLOGY and RESULTS – DETERMINE WHO IS AFFECTED IN THE NFL
Evaluating hair-length data – frequency, age and style
An analysis of the 2,905 players listed on NFL rosters from June 15-19, 2015, yielded some interesting information about the players affected by the Ricky Rule. This hair data was obtained by reviewing the internet rosters from the official websites of all 32 professional football teams to determine which players had long hair that would be affected by the Ricky Rule (13-44). If photographs were found on the official team websites, they were used in the determination of hair length. When official team websites did not include photographs of the players, internet searches were conducted to find the most up-to-date photograph available for each player. The data were then analyzed by player age, NFL conference, defense/offense/special teams units, and specific positions held, with a concentration on the ball-handling positions.

As of July 1, 2015, 14% of all NFL players had hair long enough to be affected by the Ricky Rule. Slightly more in the AFC conference had long hair then those in the NFC conference, as shown in Table 3.

The average age of players with long hair slightly older than the average age of all players, as shown in Table 4. The data were collected for the entire NFL as well as the American and National football conferences. While at some point it may have been the younger players that were the ones sporting longhaired styles, the data show that the average age of football players wearing long hair is one year older than the average of the entire population. This is true when looking at the entire NFL or individual conferences.

The trend of long-manned players has a current presence in the NFL. Albeit, the choice style of long hair shows considerable preference, it is evident that dreadlocks are a favored style making up the vast majority of longhaired players. Approximately three out of four players with long hair wear them in dreadlocks, as illustrated in Figure 2.

There are multiple techniques to achieve dreadlock hairstyle; however, the desired result is the same, where the hair is formed into rope-like strands. Bundles of hair, typically the width of a standard number two pencil, are locked using a knotting technique. This knotting technique can be as simple as looping/tying the hair into a small knot. The result is a dreadlock consisting of multiple knots or locks. From this study and analysis, it is clear that this style is worn by 74% of all players that adorn long hair. Others styles present are include loose, straight, wavy, and curly hairstyles. The majority of players with long hair have a length of hair that reaches past the shoulders to the mid/low back. Few players have long hair that reaches past the low back or above the shoulders. Overall, two trends were observed: most players with long manes typically have their hair (a) past the shoulders, and (b) in dreadlocks.

Hair type and style is important for the engineering analysis because of hair strength. One hypothesis is that the dreadlocks will weaken the hair because knots create stress points in each strand, making it safer than other types of long hair. In another hypothesis, dreadlocks may be less safe because a player may grab and pull more individual hairs because of the dreadlocks, which would cause an increase in the maximum forces transferred to the scalp.

In some cases, players with long hair have segments of human or synthetic hair attached to their real hair to gain this long and full hairstyle, usually with dreadlocks. This would be important as the hair will likely break more easily at the attachment point, reducing the occurrence of injuries. In this study, there was no way to make this determination based on the individual player photographs.

Hair length as a function of player position
The detailed analysis of the 2,905 players listed on the NFL roster as of July 1, 2015 was also evaluated by player position to see if any trends would emerge. These statistics are important since some positions have an increased likelihood of being a ball carrier, and thus are more likely to be tackled (legally, via the Ricky Rule) while wearing long hair. For example, a running back is more likely than a lineman to carry the ball, and be exposed to a tackle.

The roster information was divided up first by the unit: offense, defense, and special team. This information was gathered for American and National conferences, as well as the NFL in its entirety. It is clear when comparing the data in Figure 3 that more longhaired players play defense than offense or special teams. While 46% of all players play defense, 54% of longhaired players play defense. Defensive players are less likely to be carrying the ball, and hence are less likely to be exposed to the potential risks associated with hair tackling. Thus, the fact than fewer longhaired players are on the offensive team is a good thing. While 49% of all NFL players are offense, only 44% of longhaired players play offense.
There is a similar reduction in special teams, but it is less dramatic. While 5% of all players are specifically special teams, only 2% of longhaired players are specifically special teams.

A comparison of all NFL players to those with long hair was also evaluated for all offensive positions, as shown in Figure 4. The distribution of all NFL offensive players, regardless of hairstyle, was actually quite similar to that found of offensive players with long hair. Note that positions that make up less than 5% of the population were grouped together under the heading “other”. The only noticeable difference between the two data sets was that the quarterback position, shown in Figure 4a, is 9% of all NFL offensive players, but makes up less than 5% of those with long hair. Again, this is a good thing as the quarterback position handles the ball more than any other position, so the high frequency of short hair means less of a chance for hair-pulling injuries. Additionally, more guards and running backs were found to have long hair. It is noted that although running backs are tackled frequently, they more commonly have long hair, which means an increased chance for injury due to hair tackling.

A similar analysis was conducted of all defensive positions, as described in Figure 5. The distribution of defensive players with and without long hair was very similar. In fact, no significant differences were found.

Finally, the positions where the player typically handles the football were also investigated, as these would be the players most likely to be tackled. It was hypothesized that if there would be any differences between the general NFL population and those with long hair, it would be in the positions where the player most commonly has the ball. As was described above, those are the positions that are governed by the Ricky Rule and open to hair tackles. This is where some differences become more apparent, as shown in Figure 6; it appears that the ball handler’s long hair seems particularly popular with running backs, and considerably unpopular with quarterbacks.

NFL CASE STUDIES
Since all NFL games are televised, there are many examples of NFL players either being tackled by their hair, or encountering incidental hair contact while being blocked. The following three examples are offered as case studies. In each case, video of the incident was discoverable from a simple internet search, and the study tells a dramatic tale.

Troy Polamalu – the anatomy of a dramatic hair tackle in 2006
Pittsburgh Steeler’s strong safety Troy Polamalu was well known for his long, wavy, Samoan hair. After a defensive interception in October 2006, Polamalu’s was hair-tackled by Kansas City Chiefs running back Larry Johnson. The play was captured very clearly on video. In April 2015, Adam Teicher, a staff writer for ESPN called this play, “one of the most memorable tackles in NFL history” (51). Screenshots from the video of the interception and hair tackle are shown in Figure 7. The total playtime was 23 seconds, and a video analysis of the play showed the following five stages:

Clean defensive interception of the ball by Polamalu.
Polamalu runs for 31 yards, reaching a maximum velocity of 9.6 yard/second.
Larry Johnson grabs Polamalu’s hair in downward motion. Johnson is dragged for 5 yards
The force on Polamalu’s hair becomes horizontal. Polamalu summersaults and tumbles for 5 yards. Johnson follows, maintaining his grip on Polamalu’s hair
The force on Polamalu’s hair becomes upward. Tumbling abruptly stops as Polamalu gets back to standing position. Johnson maintains his grip on the hair.

Johnson was ultimately penalized 15 yards for unsportsmanlike conduct in not letting go of Polamalu’s hair immediately after the tackle. In an interview with the Pittsburgh Steelers’ Athletic Trainer, John Norwig (12), the investigators were told in 2015 that: “…Polamalu reported no injury or significant hair loss.” Additionally, on October 16, 2006, Polamalu told Robert Dvorchak of the Pittsburgh Post-Gazette, “No, it didn’t hurt. It felt good.” He did concede that he had never been dragged down by his hair before. He went on to say “No, but if I got the ball in my hands, they can tackle me all day like that, we had a lot of fun out there.” “Although Johnson held onto Polamalu’s hair too long and it looked as though he twisted it when Polamalu bounced back up after the tackle and the play was over, he later explained that he tried to let go but his fingers got stuck” (4).

The investigators consider motives that Polamalu may have had to minimize reports of discomfort. Namely, he wears his hair as a symbol of his Samoan heritage. Also, Head and Shoulders, a key Polamalu sponsor, later insured his mane by Lloyds of London for one million dollars (2). Clearly, Polamalu had strong reason to want to avoid the NFL disallowing long hair on their players. Personal freedoms of NFL players to wear their hair as they desire are described later in this paper.

Marshawn Lynch – The Loss of One Dreadlock Draws Player’s Attention
In September 2014, Seattle Seahawks running back, Marshawn Lynch, was tackled by Denver Broncos strong safety, Terrell Ray (T.J.) Ward, Jr. What was notable in this play was that while Lynch apparently only lost one dreadlock, he immediately felt that it was gone, found it on the sideline and put it in his waistband. It is unknown if the dreadlock tore at the base of the helmet or at the scalp, but it clearly got the attention of Marshawn Lynch. Hence, it is assumed that even the loss of one dreadlock caused enough pain to get the attention of Lynch. This seems inconsistent with Polamalu’s claim of minimal pain in 2006. Screenshots from the Lynch incident are shown in Figure 8.

As Justin Tasch from the New York Daily News pointed out on September 21, 2014, Lynch did not say a word to Ward afterword, nor did he make any sort of gesture. He did not even look at him. Lynch simply bent over to pick up their hair that was on the turf and walked away (50). It is unknown if this was a natural dreadlock or one that was added to his hair to achieve a certain hairstyle. Either way, this case study supports the hypothesis that dreadlocks are safer than other long hairstyles.

Andre Ellington – Dreadlocks Stick to the Opponent’s Gloved Hand
In 2013, Arizona Cardinal running back Andre Ellington lost a handful of dreads during a tackle by Jacksonville Jaguar outside linebacker Jason Babin. Screenshots from this incident are found in Figure 9 (52). What was unique about this hair loss was that after the play, the half-dozen or so dreads that were pulled out of Andre Ellington’s head seemed stuck to Jason Babin’s gloved hand. This illustrates that most NFL players do not have bare hands, but wear specialized gloves for increased traction with the ball. This also increases the friction during tackles and hair grabbing, hence increasing the forces transmission to the scalp and neck.

On November 17, 2013, Babin, a 10–year veteran in the NFL, was quoted by the Florida Times-Union as saying, “It’s been a while since I tackled someone by their hair. Remember, I started playing when horse-collaring was still acceptable. It was one of those things that happened in the moment. I wasn’t trying to get his dreads. If I have to make a tackle, I’m going to make a tackle. That’s more important.” He went on to say, “I didn’t even realize it, but they were stuck to my glove. I was walking back to the huddle and said, ‘What is this?’ Sometimes that stuff happens.” (53)

Meanwhile Andre Ellington was also quoted by the Florida Times-Union as saying, “At the time I didn’t know what was going on, I was getting tackled and I looked and saw that he had a handful of my hair. It was a little dirty play by their part, but its okay, we got the win. I didn’t feel it at all, with the adrenaline flowing, I didn’t feel anything.” The Cardinals had a staffer retrieve Ellington’s hair from the field. It was bagged up and given to him back in the locker room. “I got the hair back,” Ellington said. “I’ve lost some before, but not that much came out at once like this. Guys don’t intentionally try to grab it out. I think he was trying to grab it and pull it out.” So it appears that Andre Ellington thinks that this was perhaps an intentional hair grabbing. As with the Marshawn Lynch case study, is unknown if these were natural dreadlocks or not. Either way this case study supports the hypothesis that dreadlocks are safer than other long hairstyles.

NON-NFL EXAMPLE OF HAIR PULLING
While this paper clearly focuses on hair pulling examples in the NFL, hair-pulling events can be found in other athletic sports. A particularly blatant example of hair pulling in woman’s soccer occurred in 2009 during the semifinals of the Mountain West conference tournament of women’s college soccer. During a contentious game between the University of New Mexico and Brigham Young University (BYU), New Mexico player Elizabeth Lambert viciously pulled BYU player Kassidy Shumway’s hair, which was styled in a braided ponytail. It is a hypothesis that a ponytail hairstyle is the style more likely to cause injury if aggressively grabbed and pulled. This is because nearly all the individual hair strands are brought together in one place, making it easier for all of the hair to be grabbed and pulled by just one defender’s hand. In addition, ponytail bands often sit high on the head, meaning a much greater torque (moment) and resulting forces on the neck.

The force of the pull caused Shumway’s legs to buckle and took her to the ground, as is shown in screenshots from the game in Figure 10. Lambert was later flagged for continued penalties on the field. However, the Associate Head Coach of Women’s Soccer at BYU, Chris Watkins (55), impressed by the toughness of his players, told this researcher that “the BYU coaching staff did not see what happened to Shumway until later reviewing the videotape from the game, and Shumway did finish the game.” In fact, BYU went on to beat the University of New Mexico. In an interview conducted in April 2015, Kassidy Shumway told these researchers “I did complain of neck pain more than usual, probably due to whiplash.” (48) As this was a soccer game, such hand movements are strictly disallowed, but that does not mean that they do not happen. In fact, the ponytails and braids so common in women’s soccer makes them especially susceptible to neck injury since the entire head of hair can be easily grabbed at once. Beyond athletics, these type of injuries occur during domestic abuse and similar acts of violence, often against women, where non-athletes could suffer severe neck injuries.

METHODOLOGY & RESULTS – ENGINEERING ANALYSIS
Dynamic calculations
The video analysis of the Troy Polamalu tackle was used to calculate the velocity of the players and the forces that were put upon the Polamalu’s head during his hair tackle. A work-energy dynamic analysis was used to estimate the forces applied to the head of the player as a function of the angle at which the hair is grabbed. The calculations are shown in Figure 11. The equations are based upon the free body diagram shown in Figure 12, with the player modeled as a non-rotating, non-collapsing rigid body. A 2-dimensional side-view analysis was conducted that neglected neck twist, ground friction, hair breakage, and the effect of the player’s helmet.

With angle theta, θ, defined in the free body diagram, it was shown that the force exerted on a player’s hair increases steeply as θ approaches 90°. Specifically these forces ranged from 100 pounds at 0°, 200 pounds at 60°, and 600 pounds at 80°. This increase in force is due to the cosine of 90°, which equals zero, being located in the denominator. As the angle approaches 90°, the force technically approaches infinity, although what would actually happen would be hair or bone breakage, disallowing a force of infinity to actually impact the player. Regardless, the force does increase as θ approaches 90°, as defined in the free body diagram, and shown in the force plot in Figure 13.

If one were to include ground friction, and assume it was equal to the horizontal component of the hair pulling force, this would reduce the hair forces by half. This is a reasonable assumption during stage 3 of the Polamalu hair tackle (during the tackle, prior to tumbling). The range of hair tensile forces shown in Figure 13 are an average force over the 10-second tackle over 10-yards (stages 3 and 4 described in prior section). Therefore, peak forces will be even greater than these reported. In addition, Polamalu’s legs are actively adding force to propel him forward and trying to break the tackle, which would also increase the forces transmitted to the hair. At the start of stage 4 of this tackle (the tumbling stage,) nerve sensation may have caused Polamalu’s body to collapse to reduce the scalp, head, and neck forces. This may be what happened during Kassidy Shumway’s ponytail hair pulldown as well. Collapsing the body to reduce scalp pain and resulting head and neck forces is a hypothesis. Including the non-rigid links and thousands of internal connecting tissues would improve accuracy, but are beyond the scope of this research. This simplified analysis and results are reasonable since some of our assumptions increase the force, while others decrease the force.

Experimental research to test hair strength of various hair bundles and dreadlocks style is proposed that would determine the maximum force transmitted to the player’s head and neck before the hair would break, which would better define the maximum force that could be applied to a player’s neck during a similar hair tackle. That hair stands may pullout of the scalp before breaking, and the maximum strength a tackler can hold onto hair are aspects that needs to be considered for future research to improve the accuracy of the analysis presented above.

When is long hair the most dangerous and what could happen medically?
NFL player hair is worn in a variety of styles, but the demographic analysis conducted clearly shows that the most popular longhaired style is dreadlocks. From an engineering standpoint, dreadlocks may be the safest. Just as the knotting of a rope makes it weaker (47), the knotting of hair also weakens it. Weakened hair on the playing field is a good thing since if it is grabbed it is more likely to tear, and less likely to transmit the force to the player’s skull and neck. This was illustrated by the case studies of both Marshawn Lynch and Andre Ellington.

A player wearing their hair loose and natural, without dreadlocks, as was worn by Troy Palomino, is of intermediate danger. While the hair is stronger, and more likely to transmit force through the skull to the neck, it is unlikely that all of the hair would be grabbed at once.

Finally, as was shown in the example of women’s soccer player Kassidy Shumway, perhaps the most dangerous way a player could wear their hair is in a ponytail or other technique that brings it all together. The danger becomes that an opponent could grab all of the hair, increasing the likelihood of force transmission to the skull and neck.

What kind of injuries could we expect if a player has their hair pulled, and it does not break or pull out at the scalp, but instead transmits the force from the scalp to the neck? It is not just the magnitude of the force that must be considered, but also the twisting motion of the neck. The neck could twist along three axes: chin up/down, chin right/left, and chin rotating clockwise/counterclockwise. This twisting moment due to some types of hair tackling is similar to face-making, or grabbing and pulling/twisting a facemask, although the perpendicular distance from the off-centered hair-pulling tension to the center or the spine would likely be shorter than the perpendicular distance from the spine to the end of the facemask. It is against the rules in the all levels of American football to grab a player’s facemask as it can cause this type of severe twisting moments on the neck and possible injury. To minimize the occurrences of face-masking injuries, referees penalize a play up to 15 yards. However, in the NFL there is less of a penalty deterrent for hair pulling.

It is likely that a hair pull will affect all three axes of forces and moments on the neck at the same time. Shear force could be significant. Neck compression forces will increase as the pulling angle is increased downward from the horizontal axis, equal the shear force at 45 degrees, and increases tremendously at higher angles (Figure 13). The shear forces can result in slipped disk, spinal cord damage, while the compression forces can result in cervical fractures. Damage to neck tendons, ligaments, and/or neck muscles are likely. This could result in a minor sprain, pulled muscle, or torn cervical ligament or tendon.

THE ETHICAL QUESTIONS
The engineering work-energy dynamic analysis shows that the impulsive forces that can be applied to a player’s neck during a tackle could be very significant, up to 500 pounds or more, potentially causing high shear and compressive stresses in the neck, as well as neck torsion, that could cause severe and life-changing injuries. Hence, long hair in athletics, specifically the NFL, is an issue of ethical responsibility. For this paper, we have identified two ethical situations: they include the NFL’s responsibility for the safety of their players, and the responsibility of each player to keep both their teammates and competitors safe. On the other hand, the low occurrence of reported hair-pulling injuries in the NFL, as well as the desirability of exposed long hair by professional players, has been the reason to keep the Ricky Rule.

The ethical responsibility of the NFL to keep their players safe
The NFL addressed hair length in 2003 with the Ricky Rule. Since then the owners have debated issues such as player name obstruction by long hair, but have not readdressed the issue of the safety of their players with long hair. Some of the players with long hair seem to consider it an issue of personal expression. So should the NFL allow this personal expression and when employed is it reasonable for a player to lose the ability for certain personal freedoms? If so, should a hair tackle be legal?

Already the NFL players give up some personal freedoms; for example if they wear bracelets, they must be under the uniform. Even the player’s ability to wear the socks or shoes of their choice is limited by the NFL and its sponsorship programs. Hence, it is possible that hair length could also be regulated. This would likely be unpopular with many of the players who wear their hair long, so additional research must be conducted regarding the transmission of force through the hair to the skull and neck. Long hair is popular, worn by 14% of the NFL players in 2015. It may be a reasonable compromise to only allow dreadlocks that are knotted or sewn in, and disallow ponytails or braids that compress all of the exposed hair into one grab-able area. It is the concern of these authors that a catastrophic injury of a player tackled via his hair would occur before additional attention is paid to this issue.

The Ethical Responsibility of NFL Players to Keep Each Other Safe
A second ethical issue brought to light by this paper is the responsibility of a player to not blatantly pull the hair of another player, as was allegedly done by Elizabeth Lambert to Kassidy Shumway. While incidental hair pulling will be allowed as long as the Ricky Rule is still valid, NFL players must not target each other’s hair in an attempt to cause discomfort or injury. NFL referees need to look for this type of targeting, and perhaps rules such as those in place for facemask grabs should be in place for hair pulling during blocks or against players that are not carrying the ball. Thus far, it seems that players have done a reasonably good job of regulating themselves (45). It is not just an issue of sportsmanship, but also one of safety.

CONCLUSIONS
This study investigates the injury potential that long hair poses for athletes playing American football. Personal foul penalties can be called for grabbing and pulling long hair during tackles and other contact situations at the high school and collegiate levels. However, this is not the case in the professional level. The NFL addressed the topic of hair pulling in their 2003 Ricky Rule, stating that a player’s hair is part of his uniform; hence, Uniform Rules apply, and a player may be tackled by their hair. An analysis of 2,905 NFL players showed that 14% of players have hair length to or beyond their shoulders, consequently controlled by the Ricky Rule. Of the most common ball handling positions, long hair was most popular in running backs, and least popular in quarterbacks. Running backs have the greatest chance of being ball carriers, and thus the greatest chance of being tackled by their hair. Of the players with long hair, 74% wear it in dreadlocks. We believe that this is a good thing since dreadlocks should break more easily than non-knotted hair. Case studies showed that players can be tackled by their hair, and some players notice when even one dreadlock is ripped off during a play. An additional case study indicates that player in other sports can be taken down by their hair, even in soccer, where you would think that hair tackles are less likely due to rules regulating hand involvement.

A dynamic engineering analysis indicated that the forces impulsively applied to a player’s hair during to an NFL tackle exceeded 500 lb. This type of hair pulling can cause shear, compression, and multi-axle moments (twisting) of the neck. These forces have the potential to cause minor to severe player injury.

Ethically the freedoms of players need to be weighed with their safety. At the minimum, players need to be educated about the potential dangers of long hair in athletics. Athletes with strong neck muscles, needed to protect the athletes during normal contact, have greater protection from injuries due to hair tackling. However, with the substantial number of players having long hair, and the permission of hair tackling in the NFL, athletes with long hair are putting themselves at risk for injury.

APPLICATIONS IN SPORT
Players, coaches, and referees need to be informed about the potential dangers related to long hair in sports. In high school and college football, most referees penalize hair contact with a personal foul. Meanwhile, the 2003 Ricky Rule regulates hair contact in the NFL, where Uniform Rules are applied to hair contact once the hair length reaches the player’s uniform. Consequently, players can be tackled by their hair. The dynamic engineering analysis conducted shows impulsive tensile hair loads in excess of 500 lbs. Players in all sports need to decide if they want to expose themselves to such risk. Ultimately, it becomes an ethical issue of player freedom versus risk.

ACKNOWLEDGMENTS
None.

REFERENCES
1. Alder, J. (2017). Football 101 – special teams positions. ThoughtCo. Retrieved from http://football.about.com/cs/football101/a/positionspec.htm
2. Associated Press. (2010, August 30). Troy Polamalu has hair insured. ESPN.com. Retrieved from http://www.espn.com/nfl/news/story?id=5513644
3. Colgate, R. (2017, August 01). Email correspondence.
4. Dvorchak, R. (2006, October 16). Steeler’s victory had everything, including a bizarre hair tackle. Pittsburgh Post-Gazette. Retrieved from post-gazette.com.
5. ESPNEWSHD RcJ2. (2009, November 06). Elizabeth Lambert of New Mexico Lobos suspended [Video file]. Retrieved from https://youtu.be/PJiRQsyrBoI
6. Grunewald, C. (2014, October 29). Marshawn Lynch lost a dread [Video file]. Retrieved from https://youtu.be/ytTx4sgAzos
7. Harris, N. (2010). Elite clubs on Uefa gravy train as Super Bowl knocked off perch. The Independent Sport. Retrieved from http://www.independent.co.uk/sport/football/european/elite-clubs-on-uefa-gravy-train-as-super-bowl-knocked-off-perch-1884429.html.
8. Jozsa, F. (2004). Sports Capitalism: the foreign business of American professional leagues. pg. 270. Aldershot, Hants, U.K., and Burlington, Vt.: Ashgate Publishing Limited.
9. Long H. and Czarnecki, J. (2015). Football for dummies (5th ed.). Hoboken, NJ: Wiley Publishing.
10. NFL digest of rules. (n.d.). Use of hands, arms, and body. Retrieved from http://www.nfl.com/rulebook/use of hands.
11. NFL teams. Fox Sports. (2015, June 15). Retrieved from http://www.foxsports.com/nfl/teams
12. Norwig, J. (2015, April 9). Personal interview.
13. Player roster Arizona Cardinals. (2015, June 17). Retrieved from http://www.azcardinals.com/roster/player-roster.html
14. Player roster Atlanta Falcons (2015, June 19). Retrieved from http://www.atlantafalcons.com/team/player-roster.html
15. Player roster Baltimore Ravens. (2015, June 15). Retrieved from http://www.baltimoreravens.com/team/roster.html
16. Player roster Buffalo Bills. (2015, June 15). Retrieved from http://www.buffalobills.com/team/roster.html
17. Player roster Carolina Panthers. (2015, June 18). Retrieved from http://www.panthers.comf(/team/roster.html
18. Player roster Chicago Bears. (2015, June 17). Retrieved from http://www.chicagobears.com/team/roster.html
19. Player roster Cincinnati Bengals. (2015, June 15). Retrieved from http://www.bengals.com/team/roster.html
20. Player roster Cleveland Browns. (2015, June 15). Retrieved from http://www.clevelandbrowns.com/team/roster.html
21. Player roster Dallas Cowboys. (2015, June 17). Retrieved from http://www.dallascowboys.com/team/roster
22. Player roster Denver Broncos. (2015, June 15). Retrieved from http://www.denverbroncos.com/team/roster.html
23. Player roster Detroit Lions. (2015, June 19). Retrieved from http://www.detroitlions.com/team/roster.html
24. Player roster Green Bay Packers. (2015, June 17). Retrieved from http://www.packers.com/team/players.html.
25. Player roster Houston Texans. (2015, June 15). Retrieved from http://www.houstontexans.com/team/roster.html
26. Player roster Indianapolis Colts. (2015, June 15). Retrieved from http://www.colts.com/team/roster.html
27. Player roster Jacksonville Jaguars. (2015, June 15). Retrieved from http://www.jaguars.com/team/roster.html
28. Player roster Kansas City Chiefs. (2015, June 15). Retrieved from http://www.kcchiefs.com/team/roster.html
29. Player roster Miami Dolphins. (2015, June 15). Retrieved from http://www.miamidolphins.com/team/player-roster.html
30. Player roster Minnesota Vikings. (2015, June 17). Retrieved from http://www.vikings.com/team/roster.html
31. Player roster New England Patriots. (2015, June 15). Retrieved from http://www.patriots.com/team/roster
32. Player roster New Orleans Saints. (2015, June 19). Retrieved from http://www.neworleanssaints.com/team/roster.html
33. Player roster New York Giants. (2015, June 17). Retrieved from http://www.giants.com/team/roster.html
34. Player roster New York Jets. (2015, June 15). Retrieved from http://www.newyorkjets.com/team/roster.html
35. Player roster Oakland Raiders. (2015, June 15). Retrieved from http://www.raiders.com/team/roster.html
36. Player roster Philadelphia Eagles. (2015, June 15). Retrieved from http://www.philadelphiaeagles.com/team/roster.html
37. Player roster Pittsburgh Steelers. (2015, June 15). Retrieved from http://www.steelers.com/team/roster.html
38. Player roster San Diego Chargers. (2015, June 15). Retrieved from http://www.chargers.com/team/roster
39. Player roster San Francisco 49ers. (2015, June 19). Retrieved from http://www.49ers.com/team/roster.html
40. Player roster Seattle Seahawks. (2015, June 18). Retrieved from http://www.seahawks.com/team/roster
41. Player roster St. Louis Rams. (2015, June 17). Retrieved from http://www.therams.com/team/roster.html
42. Player roster Tampa Bay Buccaneers. (2015, June 19). Retrieved from http://www.buccaneers.com/team-and-stats/roster.html
43. Player roster Tennessee Titans. (2015, June 15). Retrieved from http://www.titansonline.com/team/roster.html
44. Player roster Washington Redskins. (2015, June 17). Retrieved from http://www.redskins.com/team/roster.html
45. Porter, G. (2016, March 03). 11 Unwritten rules of football [Blog post]. Retrieved from https://blogs.usafootball.com/blog/2936/11-unwritten-rules-of-football
46. Rank, A. (2012). These players inspired their own rules. NFL.com. Retrieved from http://www.nfl.com/news/story/09000d5d827ee120/article/these-players-inspired-their-own-rules-changes
47. Saitta, A., Soper, P. & Wasserman, E., Klein, M. (1999). Influence of a knot on the strength of a polymer strand. Nature, 399, 46-48.
48. Shumway, K. (2015, April 02). Personal interview.
49. Slong31390. (2006, October 15). Polamalu tackled by hair [Video file]. Retrieved from https://youtu.be/eVO93amUv7Y
50. Tasch, J. (2014, September 21). Seahawks’ Marshawn Lynch has hair ripped out by Denver Broncos’ T.J. Ward. New York Daily News. Retrieved from nydailynews.com.
51. Teicher, A. (2015, April 10). Hair Tackle was Troy Polamalu’s Chiefs highlight [Blog post]. Retrieved from http://www.espn.com/blog/kansas-city-chiefs/post/_/id/11435/hair-tackle-was-troy-polamalus-chiefs-highlight
52. The Fumble. (2013, November 18). Jason Babin rips out Andre Ellington’s dreadlocks [Video file]. Retrieved from https://youtu.be/9B8Ppl5N_Qs
53. The Times-Union. (2013, November 17). Jaguar’s notebook: Jason Babin pulls off highlight-reel tackle. The Florida Times-Union. Retrieved from http://www.jacksonville.com.
54. Vance, L. (2008, August 02). Hair-gate still lurking. Taking it to the House. Retrieved from https://lloydvance.wordpress.com/tag/nfl-hair-policy/
55. Watkins, C. (2015, March 30). Personal interview.
56. What is Special Teams? (2015, June 14). SportingCharts. Retrieved from http://www.sportingcharts.com/dictionary/nfl/special-teams.aspx
57. Young, P. (2015, May 04). Personal interview.

FIGURE LEGENDS
Figure 1: Acronyms used for defense and offense positions, and a typical player lineup.
Figure 2: Approximately ¾ of players with long hair wear it in a dreadlock style.
Figure 3: Comparison of player distribution by unit: (a) NFL in general, (b) long-haired players in the NFL.
Figure 4: Comparison of offensive player distribution: (a) NFL in general, (b) long-haired players in the NFL.
Figure 5: Comparison of defensive player distribution: (a) NFL in general, (b) long-haired players in the NFL.
Figure 6: Comparison of typical ball-handling positions: (a) NFL in general, (b) NFL long-haired players.
Figure 7: Hair Tackle of Troy Polamalu (49).
Figure 8: Marshawn Lynch loses single dreadlock (6).
Figure 9: Andre Ellington loses a handful of dreadlocks (52).
Figure 10: Kassidy Shumway goes down by her braid (5).
Figure 11: Dynamic engineering analysis.
Figure 12: Free body diagram used for dynamic engineering analysis.
Figure 13: The effects of hair pull angle on the force of a hair tackle.

TABLES WITH CAPTIONS
Table 1: American Football Conference teams in June 2015.
Table 1