Given the task definition and input, reply with output. In this task, you're given a four sentences of story written in natural language. Your job is to complete end part of the story by predicting appropriate last sentence which is coherent with the given sentences.

Sentence1: Hershel was a scrawny young man. Sentence2: He had very low self esteem. Sentence3: All the other boys his age were much bigger than him. Sentence4: Herschel began eating well and lifting weights.
In a few short months he had gained a lot of muscle and was happy.