Originally Posted by: Roundtuit 
Horses dont push carts
Tractors rarely push trailers
Cars TOW caravans
The only time I pushed a pallet truck was during manoeuvring the load to its resting place or placing the truck under the load - all other times it was pulled between point A and point B as this was easier to control direction with the steering wheels at the front of the travel direction.
Not the best analogy (but I get your train of thought). With the greatest of respect:
Its true, pulling is easier in that it doesn't require the same level of skill to get the load to follow your path, it will toe in behind you wherever you take it.
But you are not a machine designed for pulling loads. The tractor and car were conceptualised, specified, designed and engineered from the ground up by many of the best qualified brains they could gather together in the "Peoples Center for the Creation of Excellence in All Things" in Beijing, (or in our case, two chaps in a corrugated tin hut somewhere near Bromley) to achieve the specific aim of carrying and moving large amounts of weight from A to B, and is fitted with a tow hitch designed to spread the loading forces onto the best-bearing structural parts of the vehicle, equally around a strong chassis.
You are a bipedal descendant of a soft-bodied sea cucumber with a skeleton and muscle structure evolved through chance mutation to perform one function, which is to support your belly off the ground enabling movement to avoid the fangs of the Sabre-Toothed Tiger while impressing the girls hanging out around the waterhole with the ultimate aim of having a great time with Delia on Friday night thus continuing the human race (ok two functions). Our limbs were never designed to cope with great amounts of tension, or pull anything.
Great tortures over the centuries often involved hanging on walls, stretching on a rack, being drawn through streets by our arms or some other painful appendage. Never to my knowledge did Vlad the Impaler ever say to his terrified prisoner.."Right you little (insert nominal of your choice), I'll make you tell me your secrets, I'm going to push really hard on your palms, let's see how you like that!
Technically, a horse pushes a cart, in that it pushes into a horse collar and chest strap tied to the breech bars fastened to the cart. All its limbs and back are in compression. The fact that the cart is located behind them does not mean they are pulling it, the collar is pulling it, they are pushing the collar.
I'm sure there are many examples of something being easier but not necessarily being good for you.
That's why you should not pull heavy loads, but we all do because it's 'easier'.
Thank you thank you, I'm here all week :-)