As crime rates increase, living in America’s big cities can be frightening at times for many people.

To reduce the risks of run-ins with those who are violent, it’s important to know what to do in a potentially dangerous situation.

Rener Gracie, head instructor of jiu-jitsu at Gracie University in California, shared the most effective and self-protective moves, especially when self-defense tools are out of reach or have been upended by a perpetrator.

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Gracie, whose family created Brazilian jiu-jitsu and the UFC (Ultimate Fighting Championship), identified the four phases of assault in an interview with Fox News Digital.

These consist of: identifying an unsuspecting target; subduing and isolating the target; controlling and exhausting; and carrying out the assault.

"In almost all cases of predatory attacks, the perpetrator will look for an opportunity where the chance of bystander intervention is at its lowest — and the likelihood of them carrying out the attack and getting away with it is at its highest," Gracie said.

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The expert offered the following tips to avoid and escape potentially dangerous altercations.

When the probability of bystander intervention is low, Gracie emphasized the need for people to stay vigilant.

"They should have their hands free, if not carrying one of their weapons or safety defense mechanisms," he said. 

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"They should be observing their surroundings," he added. "They should not be on their phones, distracted during the transition from one point to another, where an attack could potentially take place."

He also said, "If you have a tool at your disposal, that's when that tool should be in its most ready position."

One of the greatest benefits of learning a self-defense art like Brazilian jiu-jitsu, Gracie said, is the confidence boost it provides.

"When you start to unlock your body's potential, your entire aura changes," he said. "How you walk, how you survey your surroundings, the eye contact that you make with potential attackers."

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Eye contact can also be used as a tactic to keep potential attackers in check, as the "earliest indicators" of resistance from a target are posture and eye contact, according to Gracie.

"If you're looking at someone straight in the eye as they're walking toward you in the opposite direction on the sidewalk — if you're looking straight at them and don't look away – they're on your radar, and they know they're on your radar," he said.

"The simple ability to look someone in the eye is a huge, underappreciated self-defense strategy and safety component."

When a predator doesn’t want to be caught, picking up on a potential attack early could make the person think twice, Gracie noted.

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In other words — "I'm not going to attack her because she's not the easy target that I would like," he said. 

"The attacker is always surveying the challenge, or lack thereof, in their potential target."

Another indicator of resistance is verbal assertiveness and boundary-setting, according to Gracie.

"If someone encroaches on your personal space, you have to set a boundary," he said. "It can be calm-assertive in the beginning, like, ‘Hey, don’t get any closer, stay right there.’"

In an appearance on "The Ingraham Angle" on March 1, Gracie and his wife, Eve Torres, demonstrated an escalation in this type of boundary setting.

Torres gave two verbal warnings to the attacker, played by Gracie, to back off — before she yelled, "Back up!"

"At that moment, I knew she was willing to go to war," Gracie said in the segment. "And for me, the attacker, I realized she was not the easy target I anticipated she would be."

While these tips are "critical preemptive measures of self-defense," Gracie told Fox News Digital that the challenge is feeling capable enough to enforce them. 

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"If women want to extend their innate boundary-setting capabilities during uncertain interactions with potential predators, the onus is on them to learn the skills that will give them the confidence … to protect themselves and avoid going to the hospital at all costs," he said.

The ultimate goal is to survive the encounter without injury, Gracie said.

Despite the use of tools such as pepper sprays and stun guns, Gracie stressed that the only truly reliable skills are those that have been "mastered into muscle memory."

This occurs through extensively practicing self-defense methods like Brazilian jiu-jitsu, which are "leverage-based and don't rely on you having a physical advantage over the subject," he said.

"And by that, I mean strength, speed, power and size — because in almost every case, the attacker is going to target someone who they feel is physically inferior to them."

During an assault, a response called "the amygdala hijack" will trigger the self-preservation part of the brain, in which "purely primal survival instincts" kick in, according to Gracie.

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Even when this occurs, he said, jiu-jitsu will still "reveal itself."

He added, "Jiu-jitsu is highly sought after because it only takes weeks or months for men, women or children to develop the core skills that could keep them safe in a violent physical encounter."

During "The Ingraham Angle" segment, Gracie and Torres demonstrated a maneuver in which an attacker is throwing punches.

In response, Torres backed away with her hands up and charged toward Gracie, hugging him at the waist.

"She’s wrapping my waist, her head is buried in my chest," he said. "Even though I can reach her, I have no power in these punches."

He went on, "She’ll stay here until she feels an exit opportunity, and then she pushes off."

This maneuver and other key manuevers are taught in Gracie University’s Women Empowered program, he noted.

Gracie University has 264 certified training centers worldwide, which offer various self-defense courses.

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