Normalization effect of sports training on blood pressure in hypertensives.

Exercise is recommended as a lifestyle intervention in preventing hypertension based on epidemiological findings. However, previous intervention studies have presented mixed results. This discrepancy could be associated with shortcomings related to sample sizes or the inclusion of normotensive participants. The aim of this prospective cohort study (N = 463) was to compare the chronic effect of increasing sports training time on resting blood pressure for normotensives and hypertensives. We assessed systolic blood pressure, diastolic blood pressure, body mass index (BMI), and homeostasis model assessment for insulin resistance (HOMA-IR) for 69 untreated hypertensive patients (age 20.6 +/- 0.1 years, systolic blood pressure >140 mmHg) and 394 normotensive controls (age 20.6 +/- 0.1 years) before training and at follow-up visits at 12 months. All participants enrolled in various sports training lessons for 8 hours a week. The baseline BMI and HOMA-IR in the hypertensive group were significantly higher than those in the control group. For the normotensive control group, no significant changes in systolic and diastolic blood pressure were observed after training. However, for the hypertensives, systolic and diastolic blood pressure were significantly reduced after training by approximately 15 mmHg and approximately 4 mmHg, respectively, and HOMA-IR was reduced by approximately 25%. In conclusion, the effect of sports training to lower blood pressure was confined to the group of hypertensives, which may account for the overall minimal reduction in blood pressure observed in previous intervention studies.