A sudden surge of physical activity
or bout of extreme emotional distress can precipitate a
heart attack in people at risk, according to a recent review
of medical literature.
Investigators from the University
College London, UK, found consistent evidence from previous
studies that when normally inactive people engage in a burst
of physical activity, or when people are emotionally stressed,
angry or excited, they are more likely to experience a heart
However, despite the potential
danger associated with bursts of physical activity, the
benefits of exercise very much outweigh its risks, study
author Dr. Andrew Steptoe stated.
"It is extremely unlikely
that a person will experience a heart attack on any single
session of exercise," he said. "Considering that physical
fitness and regular exercise are protective for heart disease,
my advice would certainly be to carry on exercising."
Steptoe explained that most
heart attacks occur when a piece of plaque breaks away from
the inside of blood vessels, blocking blood flow to the
heart. Vigorous exercise may precipitate this by increasing
the chances plaque will become dislodged, he said, or by
disrupting the normal heart rhythm.
Emotional stress may have
the same effect on the body, and may also put the heart
at risk by increasing blood pressure and releasing stress
hormones, Steptoe noted.
To investigate how stress
can influence the heart, Steptoe and his co-author, Philip
C. Strike, reviewed studies conducted between 1970 and 2004
that examined what people were doing and feeling in the
hours before their heart attacks.
Overall, studies found that
emotional stress and extreme physical activity were two
of the most common triggers reported by heart attack patients.
In one study of 224 patients,
more than half said they had been very upset or stressed
in the 24 hours preceding their attack.
In another study, the most
common triggers reported by 1818 heart attack patients included
heavy physical work, quarrels at work or home, and mental
Other studies showed that
the risk of heart attack appeared to increase within hours
of an earthquake, exciting sports match or high-pressure
deadlines at work. Still other research in 1623 heart attack
patients found that attacks occurred more often within 2
hours after an angry outburst.
The risk of having a heart
attack in response to stress appeared to be influenced by
how healthy people were to begin with, Steptoe and Strike
note in the journal Psychosomatic Medicine.
For instance, one study showed
that people who rarely exercised were nearly seven times
more likely to have a heart attack after vigorous activity
than people who exercised regularly.
Based on these findings,
Steptoe recommended that people who are concerned about
heart attack avoid vigorous exercise in very cold weather,
which can place further stress on the heart. People not
used to exercise should start gradually, he said, so as
not to shock the system.
Although it's impossible
to avoid all emotional stress, "we can learn to control
inappropriate emotional displays and keep negative feelings
in check," Steptoe added.
SOURCE: Psychosomatic Medicine,