Aside from keeping your wits about you, there are few more important things than strength and stamina in a life-or-death situation. (Or even just when you don’t want to look like a mouth-breather in front of your friends—that’s arguably every bit as crucial.)

Whether you are a shooter, a fighter, or a hobbyist, your lungs are your real “first-line” weapon. Even if you are unarmed when you encounter a life-threatening situation, those lungs and that stamina will at the very least get you out of harm’s way, to fight another day.

It’s difficult to fully convey what happens to your body during a gunfight, but combat is hands-down the most physically demanding thing a human being can endure, besides curling. It is a test of everything you are made of. And the weak—guess what?—don’t inherit shit. They die, in a sorry, dirty, crumpled mess at the business end of a thunder stick, at the hands of the man who trained and fought harder than they did.

O2 Trainer In Action

Over time I will hit on fitness frequently, and you will begin to see a common theme. All the cool-guy gadgets and optics and trigger jobs and new magical bullets in the world aren’t going to help you if you can’t drag your sorry ass from cover to cover to close with and defeat the threat.

Maybe I’ll just take up long-range precision shooting and bypass this. Right? Negative. I challenge you to drag yourself hundreds of meters, thousands of meters, through any kind of terrain and tell me you don’t want to whip that gun around and stick your toe in the trigger well. This applies to just about anything in life where danger is present. Not just combat. But for this audience, we will stick to that for now. Because, let’s be honest, we have a cooler hobby and job than anyone else.

You will be out of breath faster in combat than from anything else you could possibly imagine. Most of you know this, but for the sake of the article just bear with me.

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O2 Trainer In Action

What separates the quick and the dead, if you will, is your physical training. Rangers are notorious for the physical torture we put ourselves through on a daily basis. I am not in any way saying that other SOF units are not at the peak of human physicality as well, but Rangers get sadistic about it. Until your last day in the regiment, you will do things that will make other service members look at you like you are some sort of masochist (you are).

There is good reason for this type of training. It allows you to overwhelm the enemy with a violence of action they have no power or will to resist, much like a Viking war party would have presented itself to those they conquered in centuries past. The enemies of this nation get to relive that nightmare day in and day out around the world. And seeing their sorry-ass faces right before you deliver a payload of “F*** you from the Republic” into them is worth every ounce of sweat and pain you put into your training.

Now that that’s all out of the way, let me show you what you can do to give yourself the upper hand. I have the benefit of living at almost 9,000 feet above sea level in the Rockies, so oxygen-deprivation training is a daily part of life up here.

O2 Trainer In Action

There are many ways to recreate a low-oxygen environment in order to strengthen and expand your lungs. In the Ranger Regiment, P-mask, or gas mask, PT was fairly common. So was watching your drunk squad mate (that’s a lie, it was probably me) throwing up inside his mask because beer was on sale at the PX yesterday, and you and your buddies decided to declare war on cases of it while you did unspeakable things in the barracks. (Go to hell, IG, I admit to nothing.)

There are civilian versions designed to restrict oxygen as well, without the whole NBC component. And they do work. But my bearded self does not appreciate my manhood being torn out of my face every time I move in those things. They also make your face feel like your crotch after a road march. Enjoy that visual. . . .

There is a very cool alternative that I have found to be great for training, hiking, whatever. It’s small, goes right in your pocket, and is very simple to use.

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The Bas Rutten O2 Trainer looks like a futuristic underwater rebreather, but it has actually been around for a while. (No offense, Bas, you are still a strapping young lad.) I will let Bas explain how this works and the technical side of it in the videos on the page link below. I’ll tell you how I liked it and how I incorporate it into my daily life and training.

First, I love this thing: it goes literally everywhere with me. I don’t drive anywhere without playing Darth Vader in the car. It’s a great place to use it, and the looks you get are entertaining, to say the least.

O2 Trainer In Action

At this altitude it takes months—years for the lazy—to acclimate and function seminormally. And with constant travel and deployments I don’t get to take full advantage of the hemoglobin changes that occur with full-time residents. This trainer has been my saving grace. I use it during hikes, workouts, boxing sessions; whenever I can, I use it. It has 14 different interchangeable settings for the amount of airflow permitted to come through, forcing your lungs to work harder as the intake hole diameter is changed out for smaller holes, and I do change them frequently depending on my activity.

It goes into luggage without taking up any space at all. It is incredibly convenient for guys like me who move around frequently and sometimes have limited baggage space due to kit and whatnot.

The actual trainer is comfortable in your mouth, and because you don’t need to shape it like you would a football mouth guard it does not cause any sort of discomfort. You actually don’t notice it, aside from hating your life and your lungs hating you.

What really separates this device from others is not just the size, but the fact that it is designed so there is no resistance to your exhaled breath. You get your desired resistance on inhale, but you can exhale without fighting a mask. In my opinion that is a huge advantage when training. The video in the link below explains why, because I’m not a botanist, astronomer, or whatever. But it is an excellent feature.

I noticed a drastic difference in my body’s performance, even at the 14,000-feet-plus peaks I frequent in my backyard. Breathing during heavy exercise has become noticeably less labored with the improved lung strength I’ve gained through its use. While you sit around and read this you could be training your lungs.

O2 Trainer - "Fatigue Makes Cowards out of Men"

In my experience the first thing to go during a workout, firefight, you name it, is your lungs. (Because who wants to miss ARMS DAY?) And you turn into an ass-dragging mouth-breather who’s more focused on not keeling over than the task at hand.

“Fatigue makes cowards out of men.” We’ve all seen “that guy,” the one always falling out and generally being worthless. We don’t play an everyone-gets-to-participate-and-win game. So better yourself and make that shitbag look even worse because he doesn’t deserve to be standing next to you Freedom Santas.

The O2 Trainer is very easy to clean, and as Bas explained to me, for those who have a young child, as I and many of you do, it is nontoxic. So if your kid is some kind of savage like mine is and WILL eventually get her trigger pullers on it, and WILL try to eat it with her shark/hamster teeth, it will not harm her if ingested.

This piece of “kit” is essential for everyone who takes their training and their fitness seriously and wants to take their physical ability to the next level. It retails for $49.95.

For more info on this awesome little tool and to purchase, check out O2 Trainer. The video HOW TO page is definitely worth checking out to see how it really works.

O2 Trainer HOW TO Videos

For more info on this awesome little tool and to purchase, check out  O2 Trainer 
The video HOW TO page is definitely worth checking out to see how it really works O2 Trainer HOW TO Videos

This article is courtesy of The Loadout Room.