Tsunades durability isn't due to her heritage, it's due to her willpower, it was said so in the sasori, the manga never mentioned her having it due to being uzumaki it was assumed, as most things with Tsunade are assume, such as her having monsterous strength naturally, it's never stated. This is just to downplay Sakura, when in reality, the manga states them to have the same feats.
Sakuras feats are no different, hell she fought through sasori poisons on will power alone.
Feat wise , Tsunade is as normal as Sakura,