Give a way which

which sentence most needs to be revised because its description is too vague?

we hiked two miles uphill in the blooming forest today.
we sprinted back and forth in the stuffy high school gym.
we had to walk up several flights of stairs to get there.
we stretched and then slowly jogged once around the track.

The sentence that most needs to be revised because its description is too vague is, We stretched and then slowly jogged once around the track. What makes this sentence description vague is the word "once". The word "once here can either refer to two things: as soon as or when they are already around the track OR slowly jogged for ONE TIME only.