I haven't gotten this far with Sanskrit, but according to my copy of Teach Yourself Sanskirt, middle voice--called Ātmanepada--is basically the same as middle voice in Ancient Greek. That would make it analogous to pronominal verbs in Romance languages--verbs that reflect an action being done to the subject of the sentence:
Spanish:
Tengo que sentarme -- I have to sit (myself) down
French:
Je me suis réveillé à midi -- I woke (myself) up at noon
When I googled "ātmanepada" specifically, I came up with
this site:
All of the verbs we've learned so far are usually called parasmaipada. The word literally means "word for another," and it usually describes two kinds of verbs: verbs of activity (go, walk, wander, ask, stand, steal, find) and verbs used with an object (steal, push, emit). The traditional definition is that the result of the action does not go to the one who acts. So, they are "other-serving" verbs, or verbs for another.
I mention the word parasmaipada as a handy term for the verbs we've studied. In this lesson, we'll study verbs of a different kind. These verbs are called ātmanepada, meaning "word for the self." The traditional definition is that the "fruit of action," meaning the result, goes to the one who acts. Hence, they are "self-serving" verbs, or verbs "for the self."
We can think of the ātmanepada verbs as reflexive verbs since the result of the action, whatever it is, goes back to whatever acted in the first place. For illustration, consider the verb pac, meaning "cook," in the examples below.
My Greek is too rusty for me to whip a sentence using middle voice conjugation on the spot, but from what I'm reading in TYS, it is a specific type of verb that, when conjugated in the middle voice, expresses a reflextive action that affects the subject. The website I quote seems to agree with this.
If anyone else is more knowledgeable about this, feel free to amend what I said here, but I don't think the English sentence example you provided is considered a middle voice construction in Sanskrit, as it's a description, not an action being done to the subject.