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There seems to be a deep psychological connection between forgiveness and the idea of unburdening oneself — after all, we speak of “carrying” grudges as though they were actual, physical things we haul around on our backs. And, according to a new paper in Social Psychological and Personality Science by Xue Zheng of Erasmus University, there might be a good reason for this: In a pair of experiments, students reminded of a time they’d forgiven someone seemed to respond to physical challenges as though they carried more weight, as compared to those who were prompted to think of a time they refused to forgive.

In one experiment, Zheng asked 160 undergrads to write about a time they’d experienced a conflict. Some were instructed to reflect on a time when they didn’t forgive the offender, others were told to think about the time they did forgive the person, and a third group wrote about a comparatively dull social interaction (a recent conversation with a co-worker, for example). They were then given a small physical challenge: jumping five times, as high as they could, without bending their knees.

The results suggest that the “weight” of carrying a grudge may be more than just a metaphor: Students who’d been primed to think about a time they forgave someone jumped the highest, about 30 centimeters. Those prompted to think of a time they withheld forgiveness, on the other hand, jumped about 22 centimeters on average. (Zheng found no significant difference in the jumps of those in the non-forgiveness and neutral conditions.) In another, similar experiment Zheng reports in the paper, people who’d been set up to think about a time they held a grudge estimated that a hill was steeper than people who were thinking about a time they forgave someone.

This is another entry in the growing field of embodied perception, the idea that the way we interact with our mental and physical realities are heavily intertwined. (For instance: Offer someone a warm cup of tea, and they’ll feel more warmly toward you.) “A state of unforgiveness is like carrying a heavy burden — a burden that victims bring with them when they navigate the physical world,” Zheng and her team conclude in their paper. “Forgiveness can ‘lighten’ this burden.”