A Cessna 172 trimmed all the way down to 65kts would require all your power to keep it level if you added the power in all the way. Once an aircraft is trimmed it's trimmed and you aint gonna stop it from running off unless you manage your power.

In this situation it's not about overpowering trim. If it's trimmed at 135 that's where it's going to fly. If you're going to floor it with the levers then you need to re-trim to get away from that setting and not just try to overpower it.