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[Hock]

From Force Science

The Fatigue Threshold: You're out of gas and the suspect is still out of control--"a cop's worst nightmare." After nearly 3 decades in law enforcement, Jeffry Johnson still remembers vividly a "hellacious" physical fight for his life as a young cop.


"I was called to a scene where a guy was banging on his girlfriend's door, trying to break in," he told Force Science News recently. "He was BIG...and on PCP. Six of us wrestled with him, trying to get his arms behind his back for cuffing.

"He thrashed around like a fire hose out of control. He got an arm free and grabbed my gun. I fought with everything I had to keep it in my holster.

"Then suddenly I was spent...no juice left. It was shocking how fast I lost strength. If other officers hadn't been there and overpowered him, I honestly believe I would have died."

Johnson, now training commander for the Long Beach (CA) PD, had reached what he calls "the fatigue threshold" and runners know as "hitting the wall," a little-researched phenomenon with profound implications for use-of-force decisions and courtroom testimony.

Spurred in part by lingering memories of his own desperate experience, Johnson has explored the causes and consequences of the condition in a recent article for the Monthly Law Journal, published online by Americans for Effective Law Enforcement, the legal information and training organization.

(To access Johnson's article, "Force and the Fatigue Threshold: The Point of No Return," free of charge, CLICK HERE or type this address into your browser: www.aele.org/law/2010-06MLJ501.html )

"COP'S WORST NIGHTMARE." In engineering, the fatigue threshold is the stress level at which steel or wood cracks, bends, or breaks. In law enforcement, Johnson explains, the term can be defined as "the sudden physical exhaustion experienced during a force encounter when an officer cannot effectively perform to either control a suspect or defend himself." It is "not the same as just being tired"; instead, it's the abrupt and utter depletion of energy "to the point that you cannot physically function."
For some officers, that dire moment can strike "in extreme cases" after as little as 30 seconds of maximum physical exertion, Johnson says. Others might last up to 5 minutes. On the whole, he estimates "an officer will be lucky if he or she has 2 to 3 minutes of effective strength in an all-out fight."

Reaching that threshold "is a cop's worst nightmare," Johnson declares. "The closer an officer gets to his or her personal fatigue threshold, the more dangerous the situation becomes, not only to the officer, but often to the suspect as well. You'll do anything to avoid it, including using what may otherwise be considered excessive force."
PHYSIOLOGICAL ROOT. Physiologically, the fatigue phenomenon hinges on the difference between aerobic and anaerobic exercise. Aerobic exertion, like jogging and biking, can be sustained for long periods of time, Johnson explains, because the body "is able to keep a steady flow of oxygen and fuel to the muscles." But anaerobic exercise, such as strength/weight training and sprinting, is critically different.

While aerobic exercise primarily uses "slow twitch" muscles designed for endurance, anaerobic effort involves "fast twitch" muscles. "These are capable of faster, more explosive motion," but they burn much more energy and are "insatiable" for fuel, Johnson explains.

Fast-twitch muscles are those you depend on in a fight for explosive motion (swinging a baton, blocking, punching, kicking, grasping, clutching, etc.) and for forceful contraction or tension (prying arms out from under a suspect, keeping him from grabbing your or his weapons, holding him down, etc.).

In such anaerobic activity, these muscles "are contracting so quickly and/or powerfully that oxygen the body is taking in cannot provide enough fuel to sustain" them for a long duration. The body tries to compensate by drawing on sugar (glycogen), but that process is not sufficient long-term. The result: a waste product (lactic acid) builds up faster than the body can expel it.

"If the body is unable either to keep the muscles fed (through respiration and blood flow) and/or remove the lactic acid," Johnson writes, muscles at some point "simply stop contracting--shut down." At this threshold, they "are literally starved and suffocated...non-responsive."

A civilian witness may not realize how much exertion an officer is expending. "It takes a tremendous amount of strength to force a person's hands into handcuffing position if the subject doesn't want to go there," Johnson writes. "A suspect can easily lock his or her arms together against or under his body.... [E]ven a suspect who is passively resisting....can easily bring an officer to his or her fatigue threshold."
Proper training--"intense, often bone jarring, high impact, task-specific training"--may extend your fighting ability somewhat, but it "doesn't eliminate the fatigue threshold--it just buys a little more time."

REASONABLE TIME FRAME. How long it takes to reach the fatigue threshold differs among individuals, Johnson says. But one scientific source he cites indicates that certain muscles can be affected after "approximately 30 seconds of maximum-intensity exercise." While "roughly" 1 to 5 minutes might seem a likely "normal" range, "don't figure on most people being able to hold out for more than 2 minutes or so," Johnson advises. "You don't have much time to get a suspect under control before you're going to be in trouble."
Important to note: the suspect may not tire as quickly as you do, Johnson explains, "because it's a lot easier to resist than to overcome resistance."

The exact point can be influenced not only by the officer's fitness level but also by such factors as the intensity of the altercation, the number of suspects and officers involved, the suspect's physical condition, environmental influences (heat, humidity, cold), the officer's equipment (20-lb. belt, motion-restricting ballistic vest, heat-retaining wool uniform) and the combatants' "will to overcome and survive," Johnson says.

The shut-down is temporary, but recovery may take as long as a quarter-hour--"precious minutes an officer can't spare in a fight," Johnson notes.
FORCE ESCALATION. Before experiencing a life-threatening loss of physical capacity, "it may be necessary for [an] officer to consider and employ greater levels of force than may otherwise appear objectively reasonable, up to and including deadly force," Johnson writes. The need for escalation may be especially urgent "if the suspect has a history of violence, has threatened the officer, or possesses a weapon."

Once an officer hits the wall, "all gains are lost, all advantages evaporate," he points out. "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...control the outcome."

In most cases, Johnson says, you can tell when you are about to reach your physical limit, although you may still be surprised at how rapidly you can fade, especially where upper-body strength is concerned. When you sense you're nearing your threshold, you "must act quickly and decisively to control the suspect," he says.

"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," he writes. "Sometimes the 4-pound pull of a trigger is the only force option a threatened, exhausted officer can physically perform.

"This will never look good on video, but appearances to the untrained eye should never dictate our standard of objective reasonableness. We carry the burden of having to explain why we took the action we did. If you explain well, people will usually accept it."
FUTURE RESEARCH. Getting into a life-on-the-line fight is rare for most officers, Johnson believes, but offering near-exhaustion as a justification for significantly escalating force in circumstances where it is a factor would be more credible to juries and review boards if more were known about the phenomenon.

"No one has yet researched the fatigue threshold in a law enforcement context," says Dr. Bill Lewinski, executive director of the Force Science Institute. "We don't know how long it takes for fatigue to strike at various levels of intensity, what the best exercise regimens are for maximizing anaerobic stamina, what techniques officers can employ to best marshal their strength in a fight, and so on. Finding answers to these and other related unknowns would be an invaluable contribution."

He and Johnson hope to collaborate on such research in the near future.
Meanwhile, Johnson writes, "experience tells us that just because a problem is not comprehensively documented does not mean it does not exist. Without question, [the fatigue threshold] exists. What we still need to more clearly establish is the scope of its impact."

[Kentbob]

Fascinating.  I suppose my biggest question would be, what steps did Johnson take in his own training and exercise regimen in order to improve is fatigue threshold?


Kent

[whitewolf]

the information provided here is valuable in that it should be included into training in  ones school-
Last week I had the students (2 police officers) take a rubber knife and use it in defense/offense tactics against a kick bag-they did it for one minute fast as possible-both were wore out when  i said time-the slashing and blocking holding the knife seemed to tire them out more than just using boxing gloves to hit the bag-
I also had them lay on thir back and wrap the legs around the bag- they then struck the bag for a minute- that was another exersise that tires them out and holding the bag with their legs was a tiring movement
if you guys can pass on some more exersises that will coorespond to the information ill tyr it.
WW

[Hock]

On this subject and the two last weeks of the Mel Gibson recorded tirade...did you notice a few times when Mel went absolutely beserk, how utterly winded and exhausted, gasping for air he was after several of the raging, emotional outburts?

Emotional exhaustion. He hit the wall sitting RIGHT in his chair.

Bill lewinski of Force Science says he can prove that anger and fear can really screw up your performance, often confusing observers who wish to chalk the problems up the presumed ogre - adrenaline.

One component of this is controlling yourself, not running the extra 10 miles while juggling clay pidgeons.

Hock

[sarguy]

Seems like it would be hard to perfectly replicate this in training. Maybe the anaerobic aspects could be mimicked through sprints, tabata work-outs, HIIT, or something of the same ilk, but like Hock mentioned, adding in fear or anger brings on the "choke". I dunno how to perfectly replicate that on a small, independent scale. Have the mother-in-law kick you in the nuts and then rack out some turkish get-ups? On a larger scale, I can see how competition might bring out some similar emotional effect, but not on the level that deadly force would. Perhaps this is where combat scenarios, mental imagery training, and stress inoculation come into play.

[JimH]

The exercises must be done against a semi or fully resisting partner.
You must learn to relax and not go into a mode where the whole body tenses ,flexes to fight and drains the energy system.
You must learn to BREATHE.
I know breathing sounds like something simple and natural but it is not.
Under stress we tend to not breathe:
When fighting a resisting opponent we are so focused on using strength and control we do not breathe fully,some do not breathe at all and some shallow breathe,you must breathe as fully as possible.

When Mel Gibson got frustrated and lost his breathe ,it was due to his not breathing.
He is an actor who has been taught to breathe and yet under stress he did not and was quickly winded.

Anaerobic training,like weight training is short duration work,which works by breathing,then using the whole body to make a movement,in the case we are speaking of trying to fight,control and or subdue another resisiting person.
Anaerobic means without oxygen,but we still need oxygen to make the system fire.

Doing Aerobic activities / activities not done against resistance and done while able to breathe regulalrly does not create the energy expenditure needed to cause shallow breathing which puts us in oxygen debt and causes rapid onset fatigue.

You can take a marathon runner and throw them into a fight with a resisting partner and they will be winded in seconds.

We train this as follows:
First phase:
We match a smaller against a bigger opponent.
Smaller man goes to the ground on his back,bigger man mounts however he wants.
The drill is the Bigger man just tries to stay on top,not really fighting back,just moving to maintain top position,(like riding a boogie board).
The bottom person must use maximum effort to get out from under.
Bottom person tires out while top person relaxes and just stays on top.
The bottom person must slow down,create space ,create an opening from which to get out and they must BREATHE.

The exercise is to give it all you have for as long as possible,rest for 1 minute and go again.
At first a 1 minute rest does not allow full recovery so when the exercise is begun again the student will tire faster unless they slow down,and breathe.
(Tabata method as applied to a resisting opponent)

[whitewolf]

JimH-good exersise thanks- another one that seeems to work is for two studens to sit back to back-they cannot get up except to knees when i say go they turn and as quickly as possible attempt to put the other on the ground and hold them -that tires one out quickly while  they rest 30 seconds and go again-i want them to tryto think ahead on how to get ahead of the other while resting-WW

[Black Knife]

"Hitting the wall" as marathon runners or other endurance athletes call it is not caused from being out of shape. "Hitting the wall" or "Bonking out" is caused from having low blood sugar or a form of Hypoglycemic.

Basically when the body can not provide glucose for the brain it causes the body too shut down ....extreme fatigue. The symptoms are nausea, lethargic, dizziness, etc. You can be in the best shape but if you consumed the wrong foods before a strenuous workout you will get low blood sugar, which will cause you to feel like shit.

You get glucose only from Carbohydrates.....but not all Carbs are good for strenuous workout or exercise. Carbs that are low on the Glycemic index are better for strenuous workouts.

I eat fruits, vegetables and grains before I workout......for an example I will make an apple and carrot juice with my juicer and I will consume it with peanut butter. The sandwich is made up of two pieces of whole wheat bread and just peanut butter.

I have various meals that I will eat for a pre-workout meal. Even when I worked the streets I made my own lunch and avoided fast foods or doughnuts and coffee. I was always afraid of getting into a good scrap and getting low blood sugar which could cause me getting my ass kicked or getting killed.