Aims: Our study was aimed at determining whether
beneficial modification of carbohydrate metabolism can be obtained
after a short-term training program and whether it is associated with
an increase in binding and degradation of 125I-insulin by
erythrocyte receptors that suggests a decrease in insulin
Methods: The study was conducted in a
group of 20 patients aged 56 ± 1.9 years (mean ± SEM), within 1
to 6 months after coronary bypass surgery. All patients completed 15
training sessions based on 30 min of cycling with a constant load.
Before and after a 3-week training program, glucose, insulin, and
C-peptide blood levels, as well as binding and degradation of
125I-insulin by erythrocyte receptors, were
Results: A statistically significant
decrease was found in the blood glucose level, from 111.2 ± 4.2 to
97.8 ± 3.5 mg/dL (p < 0.01); this decrease was not accompanied by
significant insulin concentration changes. There was also a significant
increase in insulin binding, from 0.535 ± 0.059 to 0.668 ± 0.042
pg 125I/1011 RBCs (p < 0.01), and
degradation from 7.64 ± 0.54 to 9.49 ± 0.58 pg
125I/1011 RBCs (p < 0.05).
Conclusion: The results indicated that even short-term
endurance training in patients rehabilitated after coronary bypass
surgery induced favorable modification of glucose metabolism,
presumably caused by a decrease in insulin resistance.