QUOTE (WombatOneSix @ Dec 31 2007, 04:43 AM)

I've heard numerous horror stories of new students buying these things, enthusiastically pounding away on them, then suffering from Arthiritis, seperated knuckles, and other joint problems.
Anyone put my mind at ease?
Also - what sort of hand protection should be worn when using these?
I wouldn't wear any protection, but then I wouldn't hit a wall mounted makiwara full stop. The only good place for it is the bin.
On a bag or proper makiwara I don't recommend gloves (or any other protection), but I do recommend starting to work on it really quite gently and only slowly increasing the force applied.
If you scuff your knuckles on a bag you're applying force across the bag's surface. This is to be avoided. Try to punch (whatever type of punch) so that at impact your forearm/fist forms a straight line pointing directly into the vertical centreline of the bag. This will prevent the bag spinning, minimise scuffing to the knuckles and ensure maximum transmission of force into the bag.
If you feel pain in the wrist its probably because you're hitting too hard, too early in your training and failing to ensure proper wrist alignment relative to the bag's centreline. So slow down, practice single strikes and take time to set the alignment up properly.
Most people want to put on gloves and go hell for leather, but at best this is teaching you how to box not how to hit with bare knuckles. Try hitting like that without gloves and you'll soon see how different the two sets of skills are. To hit a heavy bag without gloves in an free-form and rapid manner actually takes a lot of practice to get right without causing yourself injury. It also helps to use all the body's weapons, not just fists. Not even thinking about legs I'd recommend striking the bag with the elbow, forearm (ulna), open-hand, backfist, shoulder, hip and even the occasional (but gentle) headbutt. That way you've got lots of other tools to use when you haven't got good alignment for a punch.
Re: Mick's point about makiwara v punchbag. I do actually think they are a bit different. On the makiwara, during the impact phase, the reaction force increases (exponentially?) whereas it decreases slightly on a punchbag (once you've overcome the initial inertia). But I do think they're similar enough that only the real compulsive-obsessive types need to worry about using both. For most people a good punchbag should be sufficient, at least for the first several years of hitting it. Bagwork is good preparation for using the makiwara (I certainly wouldn't have liked to do it the other way round) and is also more versatile.
Happy new year all!
Mike