Warning: As some of you probably know, I'm kind of bad at explaining game mechanics without making them sound a bit complicated - But I'll explain this anyways;
There's now a proper system for Encumbrance - Making the Armour skills much more useful.
Your Head, Chest, Hands, Wrists, Shoulders, Legs and Feet Equipment Slots are considered 'Major' Equipment Slots.
Each piece of equipment/gear has an encumbrance value based on its Armour Class. (Light - Medium - Heavy)
The combined Encumbrance of equipment in Major Slots is added together, then averaged out to get your base Encumbrance level - Then encumbrance from additional pieces of equipment, and the weight of everything you're carrying (1% Filled Capacity would be +1 Encumbrance) is added onto that.
The higher your Encumbrance Level, (Measured at intervals of 25.) the more costly sprinting is and eventually - the more costly walking is, until you're so weighed down you just can't move at all.
Light Armour has a default Encumbrance Value of 100 (If it's an additional piece of equipment/Not in a Major Equipment Slot - It'll probably be 5)
Medium Armour would be 200/10, and Heavy Armour 300/15.
And the Encumbrance values of the equipment on your legs and feet are increased by 50%.
Your skill in every Armour Skill save for Unarmoured (Unarmoured works differently), reduces the Encumbrance value of a piece of Armour by 1 per Level. (If it's an additional piece of equipment, it'll usually take 20 Levels to decrease the Encumbrance by 1)
So a Legendary (Level 100) Light Armour User, could wear Light Armour as if it were nothing at all.
A Legendary Medium Armour user could use Medium Armour as if it were Light Armour, and a Legendary Heavy Armour user could use Heavy Armour as if it were Medium Armour.
At 350 Encumbrance, you'll be unable to move. (If you were completely covered in Heavy Armour that you couldn't, or only to some extent knew how to use - And were carrying lots of stuff with you)
At 300 Encumbrance, (If you were using full Heavy Armour, but didn't know how to use it: Or were using some additional equipment and carrying a lot of stuff.) Sprinting would cost Sprint 32 AP and 16 Energy (Making it very inefficient; Useful only if you REALLY need to move, and do something else that costs less than 18 AP.)
At 200 Encumbrance, you are just barely Over-Encumbered, Walking costs 30 AP and Sprinting costs 24 AP and 12 Energy.
At 100 Encumbrance, you can Sprint at 16 AP + 8 Energy (3 Tiles a full Turn)
At 25 Encumbrance you can Sprint 10 AP + 5 Energy (5 Tiles a full Turn)
Then there are all those random intervals between that. (Though 325 is actually still treated as 300)