Acute Effects Of Static Stretching Exercise On Mental Stress-induced Arterial Stiffening In Healthy Young Women

Acute mental stress induces an increase in arterial stiffness. It has been reported that a single bout of static stretching exercise reduces arterial stiffness. PURPOSE: To investigate whether a single bout of static stretching exercise could suppress increased arterial stiffness induced by mental stress. METHODS: Nine healthy eumenorrheic women with regular menstrual cycles (mean age ± standard deviation: 21.3 ± 1.1 years) participated in the present study. After completing a mental stress task, participants performed a single bout of a whole-body static stretching exercise protocol involving the trunk, upper limb, and lower limb (stretch trial) and sedentary rest in the exercise room (control trial) on separate days in a randomized controlled crossover fashion. A mental arithmetic task was used to elicit acute mental stress. Brachial-ankle pulse wave velocity (baPWV) as an index of systemic arterial stiffness, brachial blood pressure, heart rate, and sit-and-reach as an index of trunk flexibility were measured 20 min before (baseline) and at 5 min (immediately after mental stress task), 30 (immediately after stretch or control), and 60 (30 min after stretch or control) min after the mental stress task in both the stretching and control trials. RESULTS: Baseline baPWV showed no significant difference between the trials. Compared with baseline, baPWV was significantly increased immediately after the stress task in both trials (stretch: 956 ± 83 to 1053 ± 83 cm/sec, P = 0.03; control: 942 ± 88 to 1025 ± 85 cm/sec, P = 0.04). baPWV was significantly lower at 30 (962 ± 78 cm/sec, P = 0.04) and 60 (957 ± 79 cm/sec, P = 0.03) min than immediately after the stress task (1053 ± 83 cm/sec) in the stretch trial. In the control trial, there was no significant change in baPWV (after 5 min: 1025 ± 85 cm/sec, after 30 min; 1029 ± 99 cm/sec, after 60 min; 1035 ± 102 cm/sec). baPWV was significantly lower in stretch trial compared with control trial at 30 (962 ± 78 vs. 1029 ± 99 cm/sec, P = 0.02) and 60 (957 ± 79 vs. 1035 ± 102 cm/sec, P = 0.01) min after mental stress task. There was no significant difference between the trials or from baseline at any time point for either trial in terms of blood pressure, heart rate, or sit-and-reach. CONCLUSIONS: These results suggest that static stretching exercise can quickly reduce mental stress-induced arterial stiffening.