>>725183647
People aren't made of butter and stabbing something that's just continually shoving its weight into you is going to get very tiring very fast. You'll have to manually push it away with each thrust that doesn't kill since they're, you know, zombies, they're just going to keep swarming - and actually penetrating the head will be very difficult, skulls are quick hard, it'd be like trying to stab through a (thin) layer of brick.

Introducing: the war hammer.
You get range and you just donk them, crushes the skull and destroys the brain effectively, decently low time to kill, and since they'll just crumple you won't be doing a full workout on every zombie.