1. ANALYZING LONG HAIR IN FOOTBALL: VISIBLE IMPACT,
INVISIBLE PENALTYEmerald Alexis
Advisor: Dr. Laura Ruhala
Co-Advisor: Dr. Richard Ruhala
Department of Mechanical Engineering
16 April 2015
Abstract
Long hair is visibly observed in both professional and
collegiate football athletes. Players who adorn long hair,
leave a viable tool to aid in their takedown and possibly their
subsequent injury. While in general tackling is an essential
component of football that is carefully regulated to reduce
the occurrence of injury, in the NFL player hair is considered
to be a part of the uniform, and hence can be used in
tackles. This research project focuses on the effects of
player’s using long hair as a tackling tool. Specifically,
engineering dynamics analysis is used to evaluate the forces
applied when a player is tackled by the hair. An emphasis is
placed on how these forces can cause player injury.
Possible injury From a Mane Tackle
Neck Strain /sprain (Whiplash)
Scalp damage and Hair loss
Head or neck pain
Spinal Compression
Cervical Fractures
Analyzing The Mane Issue
In 2003 the NFL instituted the “Ricky Rule”, named after Ricky
Williams. It states that if a player’s hair reaches his jersey, it is
part of the uniform and can be used to tackle a player, but
must be released immediately following the play.
Future Work
This research project is a work in progress. Future
investigations may include more complex dynamic
models, collegiate football, different sports, hair
tensile strength and effects of athletic gloves
Other Athletes May Be At Risk
Football has an innate tackling culture. In other sports ,for
instance soccer, tackling is not allowed. However, this does
not mean that players are not pulled down by their hair in
other athletic fields. A prime example of this is the case of
Brigham Young’s Player Kassidy Shumway being pulled to
the ground via her hair braid by a New Mexico player.
Kassidy Shumway told us “….I did complain of neck pain
more than usual probably due to whiplash.”
The Anatomy of a Hair Tackle
October 2006
Tackle of Pittsburgh Steeler Strong Safety Troy Polamalu by
Kansas City Chief Running Back Larry Johnson
1.Clean defensive interception of ball
2.Polamalu runs for 31 yards, reaching max velocity of 9.6
yd/s
3.Larry Johnson grabs Polamalu’s hair in downward motion.
Johnson is dragged for 5 yards
4.Force on Polamalu’s hair becomes horizontal. Polamalu
summersaults and tumbles for 5 yards. Johnson follows,
maintaining grip on hair
5.Force on hair becomes upward. Tumbling abruptly stops
as Polamalu gets back to standing position. Johnson
maintains grip on hair.
6.Johnson penalized 15 yards for not letting go of hair
immediately after tackle
7.Total play time: 23 seconds
8.Steelers’ athletic trainer, John Norwig, tells us that “…
Polamalu reported no injury or significant hair loss”.
Current Engineering Question
How much force was exerted on Pittsburgh Steeler Troy
Polamalu’s hair during an infamous 2006 hair tackle?
Free Body Diagram
N
mg
0°
90°
Finitial
Ffinal
θ
Dynamic Work-Energy Analysis
Assumptions Made during Analysis
Player is a non-rotating, non-collapsing rigid body
2-dimensional side-view analysis neglecting neck twist
Neglected ground friction
Neglected hair breakage
Neglected effects of helmet