A quick note
Kuma with a leg and his head injured/damaged by none other than Akainu, one of the most deadly people in this series
And who has just acted as a human shield for Bonney, having Saturn strike him instead of her
Has enough endurance to still attack Saturn enough to injure him (whether Saturn allowed him because he knows he can regenerate or he was simply overpowered doesn't matter... it's just important that Kuma can move and fight against such a powerful individual)
The same Kuma (indirectly, but pretty clearly) self-admitted that Pre TS Zoro has superior endurance to him
Just how tough Zoro is??
No wonder this guy could take part of Hakai and still fight...