Officers Use of Deadly Force When Reaching the Fatigue Threshold

 By Dr. Peter A. Barone, Esq. Ph.D., LL.M., JD

 

There is a physiological phenomenon that has a great deal to do with Officers Use of Force and can be a major factor in why law enforcement officers justifiably shoot a suspect who is unarmed and engaged in hand-to-hand combat with the officer. There has been a great deal of research and writing conducted in recent years on the physiological factors that come into play when a law enforcement officer uses force. These factors, many of which stem from the “fight or fight” response within the body, will impact not only an officer’s perceptions, but also his or her ability to use force effectively. One of the major factors is known as the “fatigue threshold” (ALE Month, 2007). This is a term actually borrowed from the physical sciences and when examining the engineering branch of science we see that it means the stress level at which steel or wood will crack, bend or break. When using this term when relating to human beings, and in this case to law enforcement officers during the performance of their duties, the fatigue threshold can be understood as the sudden physical exhaustion experienced during a force encounter when an officer cannot effectively perform to either control a suspect or defend himself (Grossman, 2004).

An officer only has a short time in an all-out fight and in extreme cases less than a minute to gain control of a suspect before the officer’s energy is spent. Once the officers energy is spent or depleted that places the officer in a very precarious position which can be life threatening. If the officer continues on trying to fight or gain control of the subject without implementing some type of weapon this places him or her in a very seriously dangerous disadvantage. Once the officer hits this threshold the officer is unable to defend themselves or anyone else and they are now at the mercy of the person with whom they have been fighting with, and the law enforcement officer is now in no condition at all to protect themselves or others (ALE Month, 2007). 

                                       Physiological Root of Fatigue Threshold
Physiologically, the fatigue threshold phenomenon hinges on the difference between aerobic and anaerobic exercise. Aerobic exertion which is activity like jogging or bike riding are able to be sustained for substantial periods of time due to the body being able to maintain a fixed flow of oxygen and fuel to the muscles in the body involved in the activity. However, when we examine anaerobic exercising such as, strength training in the form of weight lifting or doing spinning drills in wrestling or wind sprints in many sports, we see that these two activities are critically different (McArdle, Katch, & Katch, 1996).     

When examining physiology and how muscles work we see that aerobic exercise primarily uses slow twitch muscles which are physiologically designed for endurance and anaerobic activities   involving what are known as fast twitch muscles. A good way to understand these muscles would be looking at the martial arts and the difference between Tai Chi with its’ slow fluid motions and Tae Kwon Do where the movements are quick and powerful. The slow twitch muscles (Type I Fibers) are slower and are used in Tai Chi and the fast twitch muscles (Type IIb Fibers) are capable of moving faster and produce more explosive motion such as those used in Tae Kwon Do (McArdle, Katch, & Katch, 1996).  

We can also understand that if we walk for 6 miles at a very slow moving pace we can keep going and do not really feel the stress in our muscles. However, if we sprint for one-half mile we can see the perspiration and feel the burn in our muscles and feel the fatigue. The fast twitch muscles burn much more energy and are insatiable for fuel.  When we examine slow twitch muscles we see they are the ones used in firing a weapon; however, the fast-twitch muscles are those you use and need to work when you are involved in a physical altercation such as a fight. The fast twitch muscles are also the ones used for explosive motion when an officer is swinging an asp, or as in the hard martial arts and they are blocking, punching, kicking, grasping, and clutching an opponent’s arms or hands.  These fast twitch muscles are used for forceful contraction or tension which are employed for activities such as an officer attempting to pry the arms out from under a suspect, (if you have had an occasion to do this you find our quickly that it can be a very difficult, arduous, and exhausting exercise) keeping him from grabbing you or your weapon or attempting to handcuff him. Slow-twitch fibers contract slowly and release energy gradually as required by the body during steady-state activity such as jogging, cycling and endurance swimming. These fibers are efficient in using oxygen to generate energy making them resistant to fatigue but unable to produce the power of fast-twitch fibers (McArdle, Katch, & Katch, 1996).   

Type IIa Fibers) which are seen as being on the fence and are somewhere halfway between type I and Type IIb and they are equal parts aerobic and anaerobic where they are not great at long distances, not great at sprinting, but pretty good for either or both such as when taking a Physical Agility Test. When a person is born they are born with these fibers in certain proportions, and they will affect how successful you are at either developing as a long distance guy, or a sprinter. Most bodies have 50% of Type 1 and 50% of Type 2 (A and B), but many elite athletes (world class marathon runners and Olympic sprinters) can have up to 80% of one or the other (Gollnick, Armstrong, Saubert, Piehl, & Saltin 1972).        
The energy that these fast twitching muscles need during anaerobic activity while they are quickly contracting is oxygen. The problem that occurs here is that the oxygen the body is taking in cannot provide enough fuel to sustain these muscles for a long duration and that is what is needed during these encounters. In order for the body to sustain the muscles it tries to compensate for the lack of necessary oxygen by drawing on sugar which is (glycogen), but again even this process is not sufficient for the long-term. The result: a waste product (lactic acid) builds up faster than the body can expel it. The problem that occurs here is if the body is unable to properly feed the muscles with what they need or remove the lactic acid then at some point in time during the extreme physical exertion the muscles will just stop contracting and it is at this point that the muscles just shut down. What has happened at this point in time is the depletion, starvation and suffocation of the muscles and when this happens the muscles are now non-responsive and the fatigue threshold has now been met (Gollnick, Armstrong, Saubert, Piehl, & Saltin 1972).        

When an incident occurs and civilian witness are viewing the event as it unfolds they may not realize how much exertion an officer is expending and they will more than likely not fully comprehend what fatigue threshold syndrome is and how it works.  Civilians have no real concept of what it actually takes, in the way of force and exertion, to force a person's hands into handcuffing position if the subject doesn't want to go there and is resisting with all of their might. If a suspect decides to lock their hands under their body and only provides minimal resistance a continued struggle with the suspect by an officer can lead to the officer to his or her fatigue threshold. Unless you have experience this activity it is very difficult to fully appreciate and understand this situation.  
Proper training, which involves very intense high impact and very task-specific training, can possibly extend an officer’s fighting ability somewhat; however, it does not eliminate the fatigue threshold, it may however provide the officer with some additional time to accomplish the objective or for additional assistance to arrive. According to Baylor and Hollingsworth (2012) it appears that sport specific training will assist in appropriate development and adaptation of each type of muscle fiber. The authors advise that fast-twitch muscle fibers benefit most by anaerobic training, such as sprint and some type of resistance training. They also advise that slow-twitch muscle fibers benefit most from endurance type activities that engage the aerobic system, such as running, cycling and swimming (Baylor and Hollingsworth, 2012). It appear that a combination of both of these methods will be beneficial to the development of the fast twitch and slow twitch muscles.  

           Variables that Effect the Time it takes to reach the Fatigue Threshold

Because each person’s physiology is different there is no absolute way to measure the exact amount of time it takes an officer to reach the state of fatigue threshold. There are a variety of variables that can also affect the amount of time it takes for the officer to reach this threshold and each individual officer in and of themselves constitute a major variable in the equation. Factors such as the age of the officer, their physical make-up such as height and weight and whether the officer works out and is in fair or good physical condition. The distance the officer has run prior to engaging in a fierce physical encounter with the assailant; not to mention the weather which could be 90 – 100 degrees with high humidity in some states and it can also be 2:30 in the afternoon in the summer in Miami as an extreme example. All of these conditions can and do have an effect on how quickly an officer can reach their fatigue threshold.  Other factors, which also must be considered, are the type of uniform the officer is wearing, the amount of equipment on their duty belt and the fact that they may be wearing a bullet proof vest with an armored plate all have a direct effect on how long it will take for the officer to meet their fatigue threshold.  

This condition, meeting the fatigue threshold, will be experienced despite the added strength adrenalin provides to the officer. The suspect will also be experiencing an adrenalin rush and the suspect will not have on a polyester uniform with a 20 pound gun belt and a bullet proof vest. When we speak of fatigue threshold we can sometimes better understand it as something that is called “hitting the wall,” which is experiencing a sudden depletion of all one’s strength and energy. When this happens it is over for the officer and there is nothing else the officer can do to include being able to pick themselves up from the ground. To support the claims made regarding fatigue threshold a study was conducted by Dr. Lewinski through the Force Science Institute (Lewinski, # 174).                                                         

                                                          Dr. Lewinski’s Study          
To fully explore this phenomenon of the fatigue threshold Dr. Lewinski, from the Force Science Institute, used a research team and conducted several unique tests with police volunteers to determine how long officers can typically endure in all-out fights with suspects and how a desperate struggle can affect memory. This specific testing was conducted under the guidance of Dr. Bill Lewinski, executive director of the Force Science Institute, the tests involved 52 officer volunteers from the Winnipeg (Manitoba) Police Service in Canada (Johnson, 2010; Lewinski, #174).

Dr. Lewinski had been contemplating research into officers’ capacity for sustaining a physical fight-for-life since he was previously consulted in a case in which a law enforcement officer from the West Coast was overpowered during a struggle and was handcuffed by a violent offender. He decided to move forward with the project after Commander Jeffry Johnson of Long Beach Police Department in California published an article questioning just how long the average officer can fight to control a combative suspect before succumbing to fatigue.
The article describes the physical fight for his life that Commander Johnson was involved in  when he was called to a scene where a subject was banging on his girlfriend’s door trying to break into the apartment. The subject was very large and was on PCP. There were several officers wrestling with the subject attempting to cuff him. The subject thrashed around and was able to get one arm free and grabbed Commander Johnson’s firearm and Johnson advised that he fought with all that he had to maintain his weapon in its’ holster and suddenly he was completely depleted of all of his energy. He was lucky that there were other officers there with him or he could have been killed by the subject. What the commander experienced during this encounter was exactly what has been discussed in his article which is "the fatigue threshold syndrome" and what runners have come to know as "hitting the wall," a little-researched phenomenon with profound implications for use-of-force decisions and courtroom testimony (Johnson, 2010).

During a certification class in Force Science Analysis, trainers attending from Winnipeg volunteered their academy facilities and assistance, so Lewinski decided to conduct the research there across 3 long days. Dr. Lewinski advised that the ultimate goal of the study was to follow up on what Officer Johnson comments on in his article and to determine how long it took an officer to drive himself or herself to exhaustion and to measure the physiological and cognitive consequences from this exhaustion or fatigue threshold (Lewinski, #174).

The study began with the officers being informed about an armed robbery crew that had attacked 3 locations. The officer were then directed to launch a full-force physical attack on a 300-lb. hanging water bag with a group of observers standing by to observe as the action took place. The bag drill realistically replicated a full-force fight by a moderately trained officer to control a strong, dynamically resisting suspect which is what occurs in a struggle with a suspect who is actively resisting being taken into custody. Dr. Lewinski advised that during this testing a couple of officers collapsed and the remainder were severely taxed as they moved forward in the exercise (Lewinski, #174).

During this experiment the issue that was most critical and most alarming was the observed rate at which the exerters depleted their physical resources. Dr. Lewinski reported that the average officer spent 56 seconds hitting the bag and some were exhausted after only 25 seconds and some actually just quit. The blows they were able to deliver averaged 183 with the overwhelming majority being fist punches. The average officer peaked at 15 seconds with the frequency of strikes falling sharply with a steady decline. By 30 to 40 seconds of the officers were significantly weakened and had difficulty breathing. At this time the blows the officers were presenting hardly moved the bag. It appeared that they were resorting largely to very weak, slowly paced blows that would have had little impact on a combative assailant (Lewinski, #174).

In addition to the officers depletion of their physical abilities they also demonstrated incomplete and faulty memories of what they experienced. They recalled less of auditory and visual activities and they made great errors in what they did attempt to recall. This study demonstrated that as exhaustion takes over, cognitive resources tend to diminish. ” Lewinski explains. “The ability to fully shift attention is inhibited, so even some potentially relevant information tends to get screened out. Ultimately, memory is determined by where the focus of attention was during an event. Dr. Lewinski’s study demonstrated that a substantial aspects of visual details may go unattended by the participants. This is critical because if investigators and reviewers of a use of force or officer involved shootings do not fully understand the findings of this study they can doubt what the officer has related about the incident to the investigators (Lewinski, # 174).

                                                   A Lone Officers Worst Fear

In engineering, the fatigue threshold is the stress level at which steel or wood cracks, bends, or breaks. In law enforcement, the term can be understood as a condition which the onset is sudden and it is actually the state of physical exhaustion which is experienced during an encounter where the use of force is exerted by the officer and when this state of physical exhaustion appears the officer can no longer physically perform in an effective manner nor can they control a suspect or defend himself themselves or others while in this state. It is very important to truly understand that this state is not the same as just being extremely tired; it is a state that arise in a very abrupt matter and it is also the utter and complete depletion of energy to the point that you cannot physically function.  As was previously discussed this state can come at any time during the time of an extreme encounter and it can occur between 30 seconds and several minutes based upon the variables previously discussed.

The closer an officer gets to his or her personal fatigue threshold the more dangerous the situation becomes. This is simply because human beings are wired to want to survive and to use whatever means available to keep themselves alive. With this mind set it creates a very dangerous situation for both the officer and the subject. The officer must fully understand what is going to occur if they actually do reach this state and take whatever action necessary prior to this condition setting in because once it does the officer will not be able to defend or protect themselves. It is dangerous for the subject because it is at this time that the officer is realizing that they are now fighting to save their lives and the survival mode will kick in and they will do what they need to survive. If an officer is reaching this level of physiological and physical depletion then there is no excessive force in keeping yourself alive when you feel and truly believe you are about to die.  

A person can sense when they are reaching their physical limit, although they may still be surprised at how rapidly you can fade, especially where upper-body strength is concerned which is what is mainly being used during struggles to take a person into custody. When the officer senses that they are nearing their threshold they must take whatever action they can and they must do it quickly and decisively to control the suspect and prevent a catastrophic result. There are times when the action that must be taken it the use of deadly force even against an unarmed assailant before the complete fatigue threshold is met. Before the officer reaches complete fatigue threshold the only strength they may have left is the four pound pull of the trigger of their weapon.  

If an officer arrives at the fatigue threshold and uses deadly force it must be remembered that it is the totality of the circumstances that must be examined at this time during these types of situations as far as the reasonableness of the amount of force used. It is reasonable to use deadly force in this situation if you are reaching this threshold and you know you are going to be helpless in the hands of the person who is physically struggling with you or trying to grab your weapon as was the case with Commander Johnson. The courts have advised that in cases like this the defense of qualified immunity is granted or withheld not on the basis of hindsight, but on the basis of what the police officer reasonably believed at the time of the shooting, given what they knew and perceived at the time the event was unfolding. The United States Supreme Court has made it very clear in the case of Terry v. Ohio (1968) that It would be unreasonable to require that police officers take unnecessary risks in the performance of their duties. As far back as the case of Tennessee v. Gardner (1985) the United States Supreme Court held that when an officer has probable cause to believe that the suspect poses a threat of serious physical harm, either to the officer or to others, the Court stated, it is not unreasonable to prevent his escape by using deadly force. It is imperative for the officer who is experiencing the reaching of the fatigue threshold and knowing they are about to lose all the ability to do anything against their opponent, that they provide a very detailed account of what transpired and exactly how they felt just before they reached the fatigue threshold. It is the totality of the circumstances that will be reviewed and examined concerning what occurred prior to the use of the deadly force being applied.  

      Documentation of what the Assailant did and what you experienced is Critical 

Due to the fact that every officer involved shooting comes with a media frenzy and comments by a plethora of Monday morning quarter backs it is critical that the officer involved in the shooting be as accurate as possible in describing force encounters in as detail as possible to include each and every action of the assailant and what they, the officer, was experiencing and feeling regarding their belief of the total fear of losing their lives.  

It is very important to vividly explain exactly how the officer felt and that the officer was  completely out of gas, had no energy left inside them and how vulnerable the officer felt when fatigue threshold totally set into place. This detailed information can be a vital factor in justifying an escalation of force if and when the officer feels they are approaching a dangerous level of exhaustion and believed that if they went unconscious, or could not even stand up of lift their hands and arms to defend themselves, that their assailant could have taken their weapon away from them and killed them and anyone else the assailant came in contact with once he took the officers weapon. As recent as June 13, 2014 a suspect who was wanted for questioning in a homicide by law enforcement in New Jersey decided to go into a Wal-Greens Drug Store at 4:00 in the morning in Jersey City New Jersey armed with only a knife. After entering the store he approached the armed security guard who was on duty and managed to take him by surprise and obtain his gun from him. The suspect has a plan which was to obtain the security guards firearm and once he did he did not rob the store or the patrons; instead he waited for the arrival for the first Jersey City Police Officer and sprinted towards the black and white police car firing thirteen rounds into the vehicle hitting Rookie Police Officer Melvin Santiago in the head who was later pronounced dead at the hospital. The offender then began to fire at other officers arriving attempting to kill more police officers and they returned fire killing him on the scene. If an officer feels they have met or are about to meet the fatigue threshold their life and the lives of others around them can be in danger and taking the proper action and making sure it is thoroughly documented is the only way to survive unless back-up arrived in time.  

Specifically documenting the suspect’s actions and what you were experiencing physically, mentally and emotionally can be essential to recreating a picture of necessary us of deadly force encounter from the perspective of the officer on the scene. This will go a long way in addressing the requirements for the standard used to assess the reasonableness of the use of deadly force and assist in the understanding of the totality of the circumstances criteria which has been established by the Supreme Court’s landmark use of force decision being Graham v. Connor, (1989). In the case of Graham v. Conner (1989) The United States Supreme Court discussed and addressed the right of a law enforcement officer to make an arrest or investigatory stop and in doing so the Court stated, that these type of action necessarily carries with it "the right to use some degree of physical coercion or threat thereof to effect it." All the law requires is that it be a reasonable amount of force based on the situation encountered by the law enforcement officer. The Court went onto say that such reasonableness, however, has to be judged in light of the facts and circumstances confronting the officer, rather than on the basis of their underlying motivation or intent. The issue that was addressed in this case was whether the officer acted in an “objectively reasonable” manner based on what they knew at the time. This is the exact reason why it is so critically important for the officer who is involved in these situations to convey in a vivid and very detailed manner the situation as it unfolded and developed along with how and what they felt and experienced physically, emotionally and mentally. The Court advised that the reasonableness of each particular use of force has to be judged and the view must be from the perspective of a reasonable officer on the scene, and must make an allowance for the fact that police officers often have to make "split second" decisions about the amount of force that is necessary. 

    Legal Perspective Involving Shooting an Unarmed Subject due to Fatigue Threshold 

In Plumhoof v. Rickard (2014) the attorney who represented the officers argued that shooting at the moving vehicle was constitutional for several reasons.  The attorney here argued that the officers in this particular case were in danger of serious bodily harm or death from the vehicle as Rickard tried to escape. Civilians and officers are allowed to use force, up to and including deadly force, to protect their life or the life of someone else that is in danger of bodily harm as was the case here. The next point the attorney argued in this case was that once Rickard had used his vehicle as a weapon he became a violent fleeing felon such that officers could use deadly force to prevent escape. Lastly the attorney argued that if Rickard had escaped he would have posed a dramatic threat to the public by his high speed flight.  Much of the oral argument focused on this last factor as plaintiff appeared to be arguing that the officers' last 12 shots could not be justified. 

In Robinson v. Arrugueta, No. 04-10856, 415 F.3d 1252 (11th Cir. 2005), the finding by the appellate court was that an officer was entitled to qualified immunity for shooting and killing a suspect in a drug transaction investigation who was slowly moving a vehicle towards him, which threatened to crush him into another car. The vehicle in this case was being used by the suspect as a deadly weapon and the officer was in total fear for his life. The court looked at the totality of the circumstances here and also saw how the suspect used the vehicle as a weapon and understood that the vehicle was not driving away from the officer but into the officer with the intent of causing great bodily harm or death. When examining the case of Webster v. Beary, No. 06-12194, 2007 U.S. App. Lexis 8142 (11th Cir.), we see that in this particular case the court found that deputies reasonably believed, at the time they shot at a car attempting to escape them by going in reverse, that a deputy who was positioned behind the car was in serious danger of great bodily harm if the vehicle hit the deputy. Due to the positioning of the deputy and the actions of the individual intentionally driving the vehicle towards the deputy they too were legally entitled to qualified immunity. The court here made a very important statement in that they advised that the fact that officers may be mistaken in considering a particular individual to be a threat to themselves or others will not bar qualified immunity as a defense, provided that the mistake is reasonable under the circumstances. If the deputy would have waited to see if the vehicle was coming towards one of them the time taken to wait to see the result could have been a deadly one which the deputies did not have to take.

These cases represent the absolute need to provide very detailed information pertaining to the actions of the suspect and the reactions and perceptions of the officer involved in the use of force situation. The Court advised that the reasonableness of each particular use of force has to be judged and the view must be from the perspective of a reasonable officer on the scene, and must make an allowance for the fact that police officers often have to make "split second" decisions about the amount of force that is necessary. The courts have provided law enforcement with the opportunity to explain what it is that they themselves saw, heard, felt and experienced during the incident which presented them with the need to use force and at times deadly force. The additional issue here is that officers should not be burdened with having to think about what will the department say or do pertaining to this incident. They should not have to be thinking about whether or not the department will have someone that is familiar with the law and has some Force Science training regarding body movements, cognitive processing and response time. They also do not need the burden of being concerned, at the time they have to make this life threatening split second decision as to whether or not the prosecutor will be aware of and used the required standard to assess their actions properly or be influenced by something outside the law. The main standard here is Graham v. Conner (1989) and we need to be consistent in its application.                                    

                                                   Reasonable or Excessive Force?

In the final analysis, the most important reason we need to have a clear understanding of the fatigue threshold is because it changes the dynamics of a force encounter. If an officer believes or knows he or she is about to reach their own fatigue threshold, and most often they will know it’s coming, they must act quickly and decisively to control the suspect. At that point it may even appear to the casual observer that the officer is winning the battle, but the reality is he’s about to hit the wall. When that happens, all gains are lost; all advantages evaporate. So what will the reasonable officer do? The reasonable officer understands that any suspect who is willing to fight the police with such intensity that he can bring the officer to the limits of his strength is dangerous and cannot be allowed to overcome the officer, gain the upper hand or control the outcome.

Particularly if the suspect has a history of violence, has threatened the officer, or possesses a weapon, it may be necessary for the officer to consider and employ greater levels of force than may otherwise appear objectively reasonable, up to and including deadly force. This will never look good on video, but appearances to the untrained eye should never dictate our standard of objective reasonableness. The law requires we place ourselves in the officer’s shoes, taking into account his physical condition at the time of the encounter. The fatigue threshold may play a prominent role in such an analysis. Again we must revert back to the Supreme Court decision which will be the legal yard stick to measure these actions by to determine the legality of their actions.

                                                              Conclusion

The fatigue threshold is a relatively new concept as relates to law enforcement. As such, there is a void of empirical data documenting specifics on the extent and character of the problem for law enforcement. However, experience tells us that just because a problem may not be considered well 

documented, it does not mean it does not exist. There is no doubt or issue of being able to clearly demonstrate the fact that the physiological process of the fatigue threshold exists and is in multiple disciplines. What needs to be done at this time is to more clearly establish the scope of its impact and also make departments, officers, investigators investigating these incidents and prosecutors who are reviewing the actions to determine the status of the officer’s actions in relation to the actions of the perpetrator. The fatigue threshold is an important concept to understand for the sake of law enforcement officers, their families, the department, the suspects and their families. An exhausted officer who has reached the limits of his or her physical endurance, yet still has not taken a resisting suspect into custody, may often have no other option than that of deadly force. Sometimes the four-pound pull of a trigger is the only force option a threatened, exhausted officer can physically perform. That’s rarely good for the officer and never good for the suspect. We cannot allow the media or interest groups sway the rule of law and the guidance that the United States Supreme Court has put down when reviewing the facts and actions of the suspect and officer. The United States Supreme Court is very clear when it advises that the reasonableness of each particular use of force has to be judged and the view must be from the perspective of a reasonable officer on the scene, and must make an allowance for the fact that police officers often have to make "split second" decisions about the amount of force that is necessary. The additional issue here is that officers should not be burdened with having to think about what will the department say or do pertaining to this incident. They should not have to be thinking about whether or not the department will have someone that is familiar with the law and has some Force Science training regarding body movements, cognitive processing and response time, and will the prosecutor use the required standard to assess their actions properly or be influenced by something outside the law Graham v. Conner (1989). “The calculus of reasonableness must embody allowance for the fact that police officers are often forced to make split-second judgments—in circumstances that are tense, uncertain, and rapidly evolving—about the amount of force that is necessary in a particular situation.” Graham v. Connor, 490 U.S. 386, at 397 (1989).

                                                            References

Gollnick PD, Armstrong RB, Saubert CW IV, Piehl K, and Saltin B. (1972). Enzyme activity and fiber composition in skeletal muscle of untrained and trained men. J Appl Physiol 33: 312—319, (http://jap.physiology.org/cgi/reprint/33/3/312).

Baylor, S.M. and Hollingsworth, S. (2012). Intracellular calcium movements during excitaiton-contraction coupling in mammalian slow-twitch and fast-twitch muscle fibers. JGP 139 (4)p.261-272 The Rockefeller University Press, doi: 10.1085/jgp.201210773

McArdle, W.D., Katch, F.I. and Katch,V.L. (1996). Exercise physiology: Energy, nutrition and human performance (4th ed.). Philadelphia: Lea & Febiger.

Police Force and the Hollywood Factor, AELE Monthly Law Journal, 2007 (4)

AELE Mo. L. J. 501

PORAC Law Enforcement News, Volume 40, Number 1 (Jan. 2008).

Graham v. Conner (1989)

Grossman, D. LTC., (2004).  On Combat, p. 15.

Donatelle, R. J., (2005).  Health: The Basics, 6th Ed., San Francisco: Pearson Education, Inc.

Plumhoof v. Rickard (2014).

Terry v. Ohio (1968).

Rust, E. and Rahnama, S. (2005), “Timing is Everything: Why the Duration and Order of Your Exercise Matters,” MedFitness, Univ. of Michigan, School of Medicine. www.umich.edu.

Hunter, S., Duchateau, J.and Enoka, R. (2005). Muscle Fatigue and the Mechanisms of Task Failure, Exercise Sport Science Review, 32(2).

Police Use of Force in America, International Association of Chiefs of Police, (2001 p.47).

Johnso J.n,L., (2010).

Force and the Fatigue Threshold: The Point of No Return Special Articles Section - June (6) AELE Mo. L. J. 501 ISSN 1935-0007

Robinson v. Arrugueta, No. 04-10856, 415 F.3d 1252 (11th Cir. 2005).

Tennessee v. Gardner (1985).

Webster v. Beary, No. 06-12194, 2007 U.S. App. Lexis 8142 (11th Cir.).