Here's my average loadout:
1911
2-4 extra mags
Smith 442
6 Spare .38SPL rounds on a speed strip
Cold Steel Recon 1 Tanto
Keys
Wallet
Cell Phone
And that's just when I am wearing a T-shirt....
So no, it isn't the least bit difficult to carry a 1911 and then some for extended periods of time. If you own a quality holster and a quality belt, it is no problem. I am fond of Eagle's BDU belt, because it does not stretch and is dirt cheap.
I use Blade-Tech IWB's for most of my carrying because they are fast, comfortable, and impervious to conditions, and they have a neat shield that extends upward from the holster to protect your soft fleshy parts from contact with the gun, especially important if you use ambi safeties on your 1911.
I routinely drive long distances with a 1911 stuffed down my pants, plus a 442 in my pocket or a P99 behind my right hip, and all the extra ammo and various other crap I carry. I never have a problem doing so.