Stress resilience isn’t a flatline. It’s a flex, according to new research from Florida International University. Marcelo Bigliassi, assistant professor of psychophysiology, and Ph.D. student Dayanne Antonio thrive in creating stressful environments.

They set out to explore how the brain’s internal wiring and a person’s subjective experience of stress interact to determine how they respond to stressful situations. The findings were published in the Journal of Applied Physiology.

Study participants plunged one hand into a bucket of ice-cold water. Frigidly cold water. As the seconds ticked by, the body’s stress systems revved up, and their skin began to sweat.