Supervisors info:
Αναστάσιος Φιλίππου, Αναπληρωτής Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Μιχαήλ Κουτσιλιέρης, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Μαρία Μαριδάκη, Αναπληρώτρια Καθηγήτρια, ΣΕΦΑΑ, ΕΚΠΑ
Summary:
Aim: Aerobic, resistance, or isometric exercise has been shown to reduce blood pressure (BP) in normotensive and hypertensive individuals. The aim of this study was to examine the acute effect of combining resistance and isometric exercise, as well as the training effect of combining 3 types of exercise (i.e., aerobic, resistance and isometric exercise) on BP of hypertensive patients. Material & Method: Fourteen adults, six females and eight males (age, 55 ± 11 yrs; BMI, 31.0 ± 6.0 kg/m2; body fat, 34 ± 14 %; waist circumference, 102 ± 18 cm; mean ± SD), with stage 1 and 2 hypertension, after the baseline measurements of biochemical (glucose, urea, creatinine, total cholesterol, HDL cholesterol, triglycerides, LDL cholesterol and HbA1c) and functional parameters (10RM in exercises: chest press, low row, shoulder extension, elbow flexion, elbow extension, knee flexion, knee extension, maximal isometric strength in a handgrip dynamometer and cycling test where HRmax, Watt max achieved, and 80% of watts achieved at HRmax), along with quality of life assessment using the questionnaire SF-36 (Physical functioning, role limitations due to physical health, role limitations due to emotional problems, energy / fatigue, emotional well-being, social functioning, pain and general health) performed a combined resistance and isometric exercise bout to examine the acute effect of this exercise combination on their BP. Afterwards, volunteers were randomly divided into two equal groups (n=7 each). One group (T) participated in an exercise training program consisted of 3 exercise sessions per week for 8 weeks. Specifically, each training session consisted of aerobic (45 min at 60–80% of maximal heart rate), resistance (3 sets of 10–15 repetitions at 60–80% of 1RM) and isometric (4 sets at 30% maximum handgrip strength for 2 min) exercise. The other group served as a control group (C) and performed 3 exercise sessions per week of isometric exercise only, at 5% of maximum handgrip strength for 2 min. Results: One hour after the resistance-isometric exercise bout, the average systolic (SBP), diastolic (DBP) and mean arterial blood pressure (MBP) were reduced by 11 ± 2 mm Hg, 6 ± 1 mm Hg and 8 ± 1 mm Hg, respectively, compared to pre-exercise levels (p < 0.001). After 8 weeks of exercise training in the T group SBP, DBP and MBP were reduced by 16 ± 4 mm Hg, 10 ± 3 mm Hg and 12 ± 3 mm Hg, respectively, compared to pre-training values (p < 0.05). These values were higher (p < 0.05) than the corresponding values in the C group, where no significant changes were observed (SBP, 2 ± 1 mm Hg; DBP, 0 ± 1 mm Hg; MBP, 1 ± 1 mm Hg; p > 0.05). In addition, as a result of exercise training, significant differences were found in the blood urea levels of the training (T) group (-7.3 ± 3.5 mg/dl, p = 0.047), while significant differences were also observed in the waist circumference (-4 ± 1 cm, p = 0.0011) compared to pre-exercise levels. In terms of functional assessment, the training group exhibited improvements in all the parameters examined by13-45% over the baseline measurements (p< 0.05), except the handgrip strength, shoulder extension strength and the maximum heart rate achieved in a incremental cycling test. The quality of life assessment revealed significant differences regarding physical functioning (25 ± 7, p = 0.026). All these values were higher (p< 0.05) than the corresponding values in the C group, where no changes were observed (p > 0.05). Conclusion: One bout of resistance-isometric exercise acutely reduced SBP, DBP, and MBP one hour post-exercise in adult patients with stage 1 and 2 hypertension, while 8 weeks of exercise training that combined aerobic, resistance, and isometric exercise resulted in a long-term reduction of SBP, DBP, and MBP.