hmm... only problem with this is if you want the cheat to be temporary, but if you want the cheats to be permanent, press the Tilde key ( ` ) then type e.g. player.modav Health 50000 or player.modav Stamina 50000
At the end of the day, its up to you if you just want to cheat cuz there's a hard quest or enemy to kill - which means the trainer would help, but if you just want it to be permanent, then just use the tilde key. But then again, the tilde key allows other things that the trainer won't, like add item, e.g. 10k gold - player.additem f 10000 or shouts player.teachword <shoutID> e.g. player.teachword 20E17, player.teachword 20E18 and player.teachword 20E19 for the Fire Breath shout.