I'm looking for a pair of Muay Thai training gloves, and am interested in why the different weights. Since I would be mainly using a bag and focus mits, with little to no sparring, would 16 ounce be optimal? I only wiegh 170, so maybe 14? Basically, why the different weight gloves--what are each weight best used for? Stupid question, but can't find out any information anywhere else. Thank in advance.