One of my favourite activities is backpacking! Load me up with 45-50 lbs for a weekend of walking and I'm happy as a clam... with legs... and a backpack.

Not a weighted vest specifically but carrying heavy things, yes. I have read Keith Norris mention in his Theory to Practice blog several times an exercise called a Farmer's Walk (video demonstration) where you carry heavy dumbbells in each hand for distance. It is considered a strongman exercise and is often part of strongman competitions. Keith seemed to hold this exercise in high regard.

Update - Keith wrote another post yesterday detailing his workout that included Farmer's Walks. Here is a portion of what he had to say with emphasis added:

Secondly, farmers walks are the most underrated exercise I know of. You want a tight core, hulking traps and Mark McGuire forearms? Do farmers walks for appreciable distance (time under tension) and with a heavy pair of dumbbells (or a heavy set of whatevers). I won’t even mention the benefit to the lower body. All the wrist curls in the world won’t come close to punishing your forearms in the way heavy farmers walks will. Low tech for sure, but functional, with a capital “F” my friends.

Weighted vests are definitely as paleo as it gets!!!!

I have tried in the past just filling up a backpack with some dumbbell weights but I didn't like how it distributed the load on my spine, especially when doing any kind of quick movement (say like a burpee with a pullup at the top which is a fav exercise of mine) ... I however have far from a perfect spine (sedentary job) so I think this wouldn't be a problem for everyone...

But recently I bought a weighted vest and it is now my favourite piece of working out equipment! I don't go to the gym I do all body-weight, functional type workouts and so it has really added a whole extra level to my workouts. I got an expensive one that has over 15 pouches (and 15 small weights), so I started really slowly just filling up 1 at a time so it was hardly noticeable.

The most amazing thing is the strength gains it gives you once you lose the vest and go back to just bodyweight stuff. I am doing muscleups now like I im on a chinup bar on the moon, infact so impressive is my new found strength (if I may say so myself!) I have started an entire muscleup craze in the park I workout at, noone was doing them before, now its hard to go for a workout and not see someone trying them!

Dr. Greg Ellis talks about walking with a heavy vest to burn calories in his "Ultimate Fat Loss Secrets" book. Cheesy name, good advice.

It seems that carrying things on your head is the most biomechanically natural way to haul heavy stuff. It allows you to stand straight up, unlike a backpack. It's not a coincidence that this is the way primitive cultures on all continents do it.

I've been foot commuting (1+ hour each way) 4 days a week all winter. I haul a 25-35lb backpack each day. It has certainly been a nice addition to my Crossfit workouts. Over the 10+ weeks of doing this, I have had some knee and back pain go away, so that now the entire walk is comfy.

Don't know of any actual science done on this weighted walking. Seems fire fighters and military personnel do this in training.

Weighted clothing and similar devices--such as weighted golf clubs and "doughnut" rings for baseball bats--have been around a long time. Weighted clothing is not just for humans. Horses are fitted with weighted shoes to train for jumps. You can add weight to any region of your body--chest (vest), back (backpack), waist (belt), thighs, ankles, wrists, feet (weighted boots)--depending on which muscles you want to work and what your goals are. The closer to the core of your body, the more weight you will need due to a lack of movement and leverage. This principle is similar to the principle of cutting weight on a bicycle--weight cut from the wheels and tires has more effect than the same weight cut from the frame (core). I think a weighted vest would be a good thing to have. You could also use it for weighted dips and pullups. Here's a good summary about weighted clothing: http://en.wikipedia.org/wiki/Weighted_clothing

In a more low tech version of packing weights around for exercise, here in Mexico I move bricks and make walkways in the garden. It might be an armload of 6-8 bricks or a wheel barrow full of them. My arms and legs both get a workout doing this.

For variety I sometimes rake water hyacinths out of the lagoon and throw them onto the shore to partly dry before wheelbarrowing them uphill to the compost pile.

I think, in general, a lot of 'weight bearing walking' can be done using normal household or garden chores.

I'm a bus-commuting doctoral student who carries a 20 pound or so back pack every day (walking at least a mile mon-fri and 3.5 on saturdays). I've started doing some upper body stuff 3x a week after the walk, while wearing the pack. Makes for a great workout.

Check out the name of Heikki Rusko of Finland he has done research on weighted vests dating way back (he was coach to the Finish x-country Ski team) The Russians used to use a method of hyper gravity with there cosmonaut's when they came back from space to speed up the recovery of muscle and bone loss...Owen Anderson also mentions weighted vests quite a bit on Peak Performance, however he mostly quotes Rusko....

Weighted walks and runs are a regular part of my routine. For those who embrace this kind of activity on a regular basis I recommend taking on a GORUCK Challenge someday. Carrying heavy stuff + working with a team + getting out of your comfort zone.

GORUCK Challenge