|“||Your physical strength determines your ability to use heavy weapons and armour without tiring, and to carry heavy loads, including your wounded comrades. Strength affects the blunt damage you do with heavy weapons, hacking-type blades, and while unarmed. It is trained faster by using heavier weapons in battle, or by traveling with a very heavy inventory or encumbrance.||”|
–in-game stats menu
Strength affects your carrying capacity before you start to slow down. In 0.33, the formula for carrying capacity is 15 + strength.
In combat, your strength exp is gained by attacking. Every strike you land, even if blocked by the enemy, is what grants you strength exp. Defending grants no experience at all.
Strength also affects the textures applied to your character. At 1 strength, a character will display no muscle. At 100 Strength, they will appear much more toned. See the picture attached.
Strength has a large effect on the speed with which characters swing 'Heavy Weapons'. At 100 Strength, a user could swing a heavy club weighing 97 kg 2-3 times faster than a dust bandit with a 2 kg katana.
An effective way to train strength would be to fill a backpack with clubs. A traders backpack would work best, and then when it is full put it in your inventory without wearing it. You then have all the weight inside the backpack working on your character. Then have them follow a guard or policeman around a city. They will then continue to walk around whilst carrying this weight, accumulating strength experience rather quickly and autonomously.
There is only one way to improve strength: USE IT! You do this by carrying around a heavy load and MOVING. The best way to do this is to load a person down with some water barrels in a large backpack or trader back pack, and use them as your trading mule (as there's currently no in game stat that affects trade prices). Within a couple of trips you will have a not so horrible strength stat. Note, doing work with a high load does not affect your strength gain, this has been tested with two characters loaded with about equal weight bags. One was set to mine ore, the other went on a trading trip. The miner is still sitting at a 1 strength (with a 12x multiplier) by the time the trader made it town, and they made it to a 4 strength. Water is good because once you start having automatic wells, you'll easily exceed production for demand to use it (especially if you put a couple of wells around near the things that need it) so you'll have plenty of excess to just put in bags.
If you have a party of more than 1 person, you can also train strength by ordering one of your people to carry the other via the 'pick up' command (hold down the right mouse button on the character to be carried) and ordering the carrier to walk as usual.