The acute effect of passively assisted trunk stretching on central arterial stiffness and blood pressure in middle-aged to older adults

Purpose: We examined the effects of acute trunk stretching on central arterial stiffness and central and peripheral blood pressure in middle-aged to older adults. Methods: Twenty-eight middle-aged to older adults (14M/14F, 72 ± 7 years, 28.5 ± 5.3 kg/m²) completed this randomized, controlled, crossover design trial. We measured carotid-femoral pulse wave velocity (cf-PWV) and central and peripheral blood pressures (BP) before and after a single bout of passively assisted trunk stretching (i.e., five rounds of six 30-s stretches) and a time-matched seated control visit (i.e., 30-min). Changes (Δ; post − pre) in cf-PWV and central and peripheral BP were compared between visits and sexes using separate linear mixed-effects models controlling for baseline values. Results: Compared with seated control, central (systolic: − 3 ± 7 mmHg; diastolic: − 2 ± 5 mmHg) and peripheral (systolic: − 2 ± 8 mmHg; diastolic: − 1 ± 4 mmHg) BP were reduced following acute trunk stretching (p_s ≤ 0.001). Between-visit differences for ∆cf-PWV (stretch: 0.09 ± 0.61 m/s; control: 0.37 ± 0.68 m/s, p = 0.038) were abolished when controlling for change in mean arterial pressure (∆MAP) (p = 0.687). The main effects of sex were detected for changes in systolic BPs (p_s ≤ 0.029); more males (n = 13) saw BP reductions than females (n = 7). Conclusion: These findings demonstrate the superiority of acute trunk stretching over passive sitting of equated duration for BP in middle-aged to older adults, with an appreciable effect in males compared to females.