I happened to catch this video on a Facebook and decided to jot down a quick list of the impedimenta these poor guys had to lug around Fallujah.
M16A4 rifle with Trijicon ACOG, Laser aiming device, weapons light or
M249 Squad Automatic Weapon and
Beretta M9 pistol
Helmet with Rhino mount and synthetic camo net
Body Armor, Carrier, loads of pouches
Ammunition load, generally 210 but these guys might be going heavier for a sustained fight
Gasmask with filters
Personal first aid kit/Bleeder pouch
Grenades, SMAW ammo, Det cord.
Communication gear, batteries, handset, etc.(Pro tip, these are not light)
Medic Pack, (Pro Tip 2, these are really not light)
AT4 Rocket launcher(s)
zip ties (used for restraints)
Camelback or 2 canteens
Buttpack / Sustainment pack
This is not to mention the various snacks, multi-tools, paper, pens, smokes, iPods, whatever other junk they accumulated in the layers of pockets and pouches. Also, clothes, belt, boots, elbow and knee pads, protective gloves, all weigh something too.
In the military, by either conventional wisdom or blind obedience to the rule book, (a.k.a. the Standard Operating Procedures), you are usually required to wear some or most of this stuff. I am sure you have seen the 300 pound "Mulisha" guy at the range, with the cross draw rig (for his primary pistol), drop leg mounted pistol (for the secondary), 21" machete MOLLE'd on the back, 12 or so magazines in various places, armor plates, but no water and a cigarette dangling from his perspiring mouth*. These guys in the video knew they would be in a sustained fight eventually. They trained for months and even years to be in the kind of physical condition to be able to drag that stuff with them up flights of stair without wheezing themselves into a little brown paper bag.
Take some time to review not only your kit but your lifestyle to make sure that you are realistically in line with your goals. Look at your gear and give it a hard look as to if you need it. You could probably do without the four knives. You will most certainly need water, navigation equipment, communication devices, medical equipment, and something to defend yourself with. If you are the Gray Man or the neighborhood watch guy or even the local militia guy, understand your physical fitness needs will be much greater than what a weekly a hour long Pilates class can give you. Like the saying goes, the more you sweat in peacetime, the less you bleed in battle. Whatever your battle may be.
*Note: This was a real life example taken from a range in Birmingham, Alabama, circa 2009. He did not carry water because, get this, he said he can always get it off of someone else. Don't be that guy.