According to the research conducted at Tufts University, the emotional burden of a secret actually takes a physical toll on its carrier and those who harbour such undisclosed truths perceive everyday tasks as far more strenuous.
Tests were carried out, according to the report, to see if there existed a relationship between metaphor and reality, the Daily Mail reported.
"Language used to describe secrets, such as 'being weighed down' or 'being burdened', suggests that carrying a secret is conceptualized metaphorically as a physical burden," the report read.
"If so, sensorimotor states associated with physical burdens could be activated or simulated when carrying a secret.
"We examined whether secrets would thus be experienced as physical burdens, influencing how people perceive and act in the world," it added.
Everyday Health broke down the study, explaining that some participants were asked to remember a life-altering secret and others a small, slightly less significant, personal secret.
Both groups were then invited to estimate how steep a hill was or how far a distance seemed.
The findings revealed that those with the meaningful secret saw the hill and distance as higher and further respectively, thus suggesting that the weight of the secret manifested itself physically.
Likewise, a group of candidates who were keeping the uncomfortable knowledge of their infidelity under wraps were more likely to perceive tasks like carrying groceries upstairs or walking the dog as requiring more of an effort.
"The more burdensome the secret and the more thought devoted to it, the more perception and action were influenced in a manner similar to carrying physical weight," the study concluded.
"Thus, as with physical burdens, secrets weigh people down," it said.