Abstract
This study shows
that heart rate can be a useful physiological
parameter to be used to estimate the
amount of glucose oxidized during exercise.
The correlation coefficients between
heart rate and GLUox were greater than
0.95 in all volunteers, both healthy and
type 1 diabetic subjects, indicating a
highly significant correlation between the
two variables. This relationship is the basis
of the “glucose pulse” concept, defined
as the GLUox expressed per unit of heart
rate. Endurance training leads to a lower
GLUox (16,17), which was also observed
in the present study with a lower glucose
pulse in aerobically trained patients. The
relationship between the glucose pulse
and the percentage of maximal theoretical
heart rate is not linear. Nevertheless, if
only a heart rate below 70% of maximal is
considered, the following linear equations
apply:
trained 0.00353 0.0023
%HRmax 0.1428 0.1328 (n 23,
R 0.846)
and
sedentary 0.00597 0.0035
%HRmax 0.1801 0.1891 (n 24,
R 0.869).
In nonobese type 1 diabetic individuals
without autonomic neuropathy, the
current equations can be used to calculate
glucose oxidation during exercise based
on easily measurable heart rate. From
these concepts, it is possible to use simple
tables matching heart rate, glucose oxidation,
and dietary equivalents to be ingested,
thus providing a potential clinical
tool for prevention of exercise-related hypoglycemia.
