Ok I'm chiming in lol
First let me answer questions
- hips/elbows: you will not hurt your dog starting it at an early age (ie: see Presa section for Anabis @ 4 months pulling)
The only way to truly hurt hips / elbows would be trying to put mass weight on the dog from the start.
- Types of weight pulling systems
* rails (like a train track w/ cart) this system is the smoothest pull for a dog and easier to pull heavier weight.
* wheels (wheel cart w/ axels like a car)
A bit harder to pull depending on what surface (carpet easier to pull on or dirt is a bit harder of the two) this will lower the amount you will start with & train on.
* snow/dirt sled even harder and varies with which surface (dirt a bit easier bc does not stick / snow the sled freezes to ground) this would even start with less weight
* drag sled a small metal or wood sled used mainly for training this you wanna start out with less weight bc it does not have a motion like wheels to continue the roll. There is a few competition who use this in the event like Irondog & ACALs Olympic Dog
- harnesses you can pretty much put into google weight pulling harness and many businesses will pop up.
The cheapest to go to is The Working Canine
http://www.theworkingk9.com/Stockharnesses.html
For a XL it starts at 58.00 I recommend her bc you are getting a great harness for just playing, training or competing.
I purchase mine from Brown Dog Design
http://weightpullharness.com/HarnessInfo.html
She is more expensive and makes for competitors
- Ages from 10-16 wks you wanna stay within weight depending on system you'll be putting on
- 16 wks to a year much more weight can start being added
- 2 and up should be pulling in the thousands if you are competing.
Well anymore info please ask
