Fast trainers are young, under-21 players who train fast. If you use Facebook amd play TE from there, then check out www.topeleven.com/play-old. Train a U21 in 3 bars practice match, and if he gets 85+ progress he's a fast trainer. Their value-to-wage ratio (called "TR factor" by nikolgiorios) should be more than 35 to be classified as a fast trainer. You can get more help here: http://forum.topeleven.com/showthread.php?t=27993 . Some players have lots of rests, so they train one of their players a lot. This is called power training. It's quite advanced (L20+ usually do it) so as of now the best bet is to buy old (26+) players, use 'em for 3 seasons, and sell 'em at the end of their contract. Do keep a few young players tho, they're easy to sell.