what if a character with 2 strength hits the gym for while? or does that just allow an increase to their might?
In my game, I accommodated this sort of play style with some custom mechanics.
There are three ways I allow my players to increase their Attributes(once per attribute):
Awakening: High time investment, results in the player gaining a permanent +1 to the relevant Attribute. If the player spends a lot of their Journey actions reading ancient tomes, honing their skills sparring against a heroic NPC, etc, they eventually receive a 1-time Awakening to the relevant Stat.
Blessing: High resource investment, results in a temporary +1 to a relevant Attribute. Sacrifice a masterly crafted artifact beneath Huge's light to receive his Blessing for a week, that sort of thing.
Corruption: High cost, results in a permanent +1 to a relevant Attribute. For the players that want to drink Demon's blood and fornicate with the Nightwalker. This one comes with a mostly narrative price that you can repeatedly hammer them on whenever something goes wrong.
If you run your game for power-gamers that want to Min-Max their Attributes, just trickle out opportunities for the above so that they don't run rampant (like dispensing Magic items).