Rex Wright, PhD
Rex Wright, PhD, is a professor in the department of psychology at the University of Alabama at Birmingham (UAB).
Did you know that pushing yourself, mentally or physically, when you’re tired may be bad for your heart? A team of researchers has verified that when people keep on pushing themselves despite being tired, their cardiovascular systems must work harder and their blood pressure may rise. We’ve all pushed through exhaustion, so I called lead researcher, Rex Wright, PhD, professor in the department of psychology at the University of Alabama at Birmingham, to discuss the findings with him.
Interestingly, he told me that an individual’s perception of the importance of the task and whether or not it is actually possible to get it done are key factors to the impact on health. “Our work suggests that under conditions where a fatigued person is presented with a task — and when success seems to be both possible and worthwhile — the harder he or she strives to meet the performance standards,” said Dr. Wright. “The result is an exaggerated cardiovascular response, which over time can lead to hypertension and heart disease.” Both the perception of stress (deadline pressure) and psychological accommodation (committing yourself to meeting it, no matter what) figure prominently in modulation of blood pressure and may impact vulnerability to cardiovascular disease.
In a recent study, 80 subjects were asked to complete a questionnaire that measured their level of fatigue, then were given the opportunity to win a small prize by memorizing, in two minutes, two or six nonsense trigrams (meaningless, three-letter sequences, such as AED). While they worked at memorizing, investigators monitored their heart rate and blood pressure. The subjects who reported “moderate” fatigue had stronger blood pressure increases even when trying to memorize the shorter sequences than subjects who reported “low” fatigue in the two-trigram condition. The study was published in the July 2008 issue of the International Journal of Psychophysiology.
Of course, few of us have the luxury of being able to stop working when we feel tired. Indeed, for some, pushing beyond fatigue is a way of life — single mothers, caregivers and people in high-stress jobs come to mind. Doing this day after day, week after week can lead to trouble and is potentially associated with hypertension, atherosclerosis (plaque build-up) and/or dementia.
It should come as no surprise that being young and healthy offers some protection — as does being physically fit. “While we have not studied this directly, I can say with near certainty that the more fit a person is, the less likely he or she is to suffer from these fatigue effects,” said Dr. Wright. On the flip side, individuals who are in vulnerable health groups are at greater risk. Our culture may celebrate hard work, but our bodies celebrate balance and appropriate rest. Get enough and your body will work better and longer.