Caveat: extremely small sample size of 13 triathletes.
The latest research involved 13 triathletes, a cognitive test called the Stroop test, and a magnesium oxide laxative.
The result? The athletes performed measurably better on the cognitive test after voiding their large intestines, a finding that suggests an underexplored link between the rectum and cognitive function. This potential link has interesting implications, not just for peak performance, but for understanding cognitive decline.