Final answer:
The context suggests that the person contemplated physical exercise out of desperation, symbolized by the idea of jumping over a bar, which represents an obstacle or limitation. The bar, in reality, is a metaphor for constraints that the characters face within the excerpt provided.
Step-by-step explanation:
The passage provided appears to indicate that the person did not actually jump backwards over a bar but contemplated exercise as a form of desperation during a period of intense emotion. In particular, the bar mentioned in the student's question could metaphorically refer to the limitations or obstacles that prevent the narrator from acting out in desperation, symbolized by the unyielding window bars in the text.
The excerpts present characters experiencing extreme physical or emotional strain, considering extreme actions, or putting forth great effort in situations that test their endurance and willpower. These scenarios are not literal but serve to convey the inner turmoil or physical challenges the characters are facing. Therefore, the reference to jumping over the bar is a metaphorical representation of overcoming challenges or acting on impulse driven by strong emotions or desperate situations.