DISCLAIMER:
This is not meant to be a definitive magical pill that will help you find the perfect fit instantly. Your first session with a Weighted Vest / Plate Carrier (PC) will not be pretty. Be mentally prepared for it to be ugly & uncomfortable.
But in time, as you understand your body & posture with an added load under fatigue, things become clearer.
With an infinite amount of permutations possible, fitting a PC is unlike fitting a shoe. It takes time (days or weeks) & patience to find what works best for you to suit your workout profile.
WHAT DOES A PLATE CARRIER ACTUALLY DO?
In the simplest form, it is designed to carry plates; ballistic plates that offer protection from various projectiles to the thoracic region that houses vital organs such as your lungs, liver, heart etc.
Does getting hit in the stomach hurt? Yes, but control the bleeding & chances are you'll live to fight another day. Getting hit in your lungs? Well we hope you remember how a chest seal works in the middle of a firefight.
Alright, let's cut to the chase!
FINDING YOUR OPTIMAL FIT
Every PC generally has 2 areas you can adjust.
1) The Shoulder Straps ( the position of where the PC sits on your torso)
And
2) The Waist Cummerbund (how snug / tight the PC fits on you.)
ADJUSTING THE SHOULDER STRAPS
To determine the height of where your PC should fit, take into consideration 2 points of reference.
First is the sternoclavicular joint, The two ends of your Collarbone that forms a pointy lump at the bottom of your neck. We feel that this is the upper limit of where your PC should sit. Any higher, you're gonna feel constricted or receive a nasty uppercut from a 4 Kilo plate to your throat / chin every time you jump.
The Second Reference Point would be your Belly Button / Navel. This is ideally the lower limit of where your plate carrier should sit without the vest cutting into your dad bod / spare tyre during burpees or squats.
Preferably, your Plate Carrier’s Panel Length should fall within these two points. (Panel lengths can be found in each PC's respective product page)
So, what about the rear? On a Lateral view, the Rear panel should sit slightly higher than the front panel. Parallel is ok as well, but anything lower & it starts to feel as if something is dragging you down.
ADJUSTING THE CUMMERBUND
This will be the section where we can offer the least advice and is really dependent on your own preference and tolerance. Again there are tradeoffs between tight & loose fits, each with its own pros & cons relative to every exercise.
Consider this. A looser fit makes it easier to breathe during runs but might slide / bounce up and down your torso while doing so. Conversely, a tighter fit prevents the PC from bouncing, but yet makes breathing more challenging.
As a general rule of thumb, form a knifehand and slot it between your vest and body and fully expand your chest by inhaling. You should not be feeling as if someone is performing CPR chest compressions on you.
"PARALYSIS BY ANALYSIS"
For every IPPT session, you are required to pin up a RFID tag. So what happens if you lose a safety pin in the middle of your 2.4KM run? Yes it sucks, but 99% of us say fuck it, let's go.
Consequently, there is no one perfect fit. If you are constantly paralyzed about your performance dropping by that 1% just because your PC is not fitted properly, then you'll never get things done. Remember, Plate Carrier WODS are meant to suck. You learn to find comfort in positions of discomfort.
In summary, Fitting your PC is a constant process as our body grows, gait changes & acclimatization improves. What feels perfect now might feel as a hindrance few years down.
Every exercise / body type is different and it takes time to find what works best for you. Be patient & focus on the work!