Just armor and also can't cast spells. And they changed it to "Armor Training" now, but still proficiency for weapons? And the Martial Weapon Training feat gives you Martial Weapon proficiency? Gah

PHB p144, under Armour Proficiency:

If you wear armor that you lack proficiency with, you have disadvantage on any ability check, saving throw, or attack roll that involves Strength or Dexterity, and you can’t cast spells.