Tanaka H, Bassett DR JR, Turner MJ
Exaggerated blood pressure response to maximal exercise in
endurance-trained individuals
Am J Hypertens
(Dec) 9:1099-1103 1996

In patients who are not trained athletes, an exaggerated BP
increase during exercise may predict future hypertension. However,
such studies have not included trained athletes, nor compared BP
responses to exercise in trained vs. untrained individuals.
Previous studies have looked at the effects of endurance training
on maximum BP response to exercise, and some have found an
increase, whereas others have found no changes.
Tanaka et al compared BP responses to exercise on a cycle ergometer
in 31
well trained endurance athletes vs. 26 controls. Mean age was
about 25
years, and the great majority of each group were men. Systolic
pressure at
maximal exercise averaged 225 mm Hg in the trained group vs. 204 in
the
untrained group, although the latter group did not reach the same
level of
work. At the same level of work, differences were much more
modest, about
10 mm Hg systolic. However, the point is made that trained
individuals
have a lower, not a higher incidence of cardiovascular risk, and
therefore
the maxim that exercise-induced hypertension connotes higher
cardiovascular
risk has at least one exception.
Comment: This is an interesting study, and shows that data
from
correlational studies needs to be applied with the target patient
in mind.
Cardiac output was not measured, and, if one assumes similar rates
of CO at
similar workloads, one is led to the conclusion of a higher
vascular
resistance in the trained individuals. Tanaka et al hypothesize
that
perhaps the trained individuals don't produce as many vasodilator
metabolites at the same workload as untrained individuals.
(John T. Daugirdas, M.D., University of Illinois at Chicago)