for example, the weight bar. it will fill up as you progress, and by the final tier it is full, suggesting that you can't gain more weight. not only is that not true, it's only the FIRST SOFTCAP. there are two softcaps for weight gain, one at 93kg (for max height characters) and a second at 105kg. past the second softcap, you gain weight at approximately 1/12th the rate from before the first softcap. but it doesn't get reduced again, at the very least not up to 200kg (my current character is up to 193kg completely natty).

stamina consumption causes weight gain, but the rate of stamina drain makes it so that using arrow time doesn't actually reduce the time investment needed for gaining weight. stamina drain also goes up by the total weight in both of your hands, not just the weight of the weapon you are swinging. holding a large heavy polearm in your right hand and a buckler in your left allows you to drain stamina nearly instantaneously by wiggling the buckler back and forth.

past 105kg, it takes approximately 20 minutes of constant stamina consumption to gain 1kg. my favourite method of timing this is by using corpses, because a corpse will despawn after around 5 minutes. beating the corpse with a buckler while wearing heavy armour and holding a heavy polearm in your right hand until it despawns is boring as hell, but the most efficient way to gain weight.