stopping the train
So, now what? Using only his strength, he digs a long painful furrow in the ground that extends well past the carnage of the nuns and orphans. He can lift 25 tons, the freight train weighs several hundred tons. He's just not more powerful than this locomotive.
If you have disabled the engine you are only working against momentum, not the trains strength. Unless you are going downhill, you will stop the train fairly quickly with 25 tons of force. If you push your strength, which seems reasonable fo rthis situation, you get up to 100 tons. You dont have to lift it either, gravity will make this stop eventually anyway, you just have to help out and 25-100 tons of force should be more than enough.