The Efficacy of Stretching Exercises on Arterial Stiffness in Middle-Aged and Older Adults: A Meta-Analysis of Randomized and Non-Randomized Controlled Trials

Abstract

Background: Aerobic exercise is known to reduce arterial stiffness; however, high-intensity resistance exercise is associated with increased arterial stiffness. Stretching exercises are another exercise modality, and their effect on arterial stiffness remains unclear. The purpose of this study was to determine whether stretching exercises reduce arterial stiffness in middle-aged and older adults, performing the first meta-analysis of currently available studies. Methods: We searched the literature for randomized controlled trials (RCTs) and non-RCTs published up to January 2020 describing middle-aged and older adults who participated in a stretching intervention vs. controls without exercise training. The primary and secondary outcomes were changes in arterial stiffness and vascular endothelial function and hemodynamic status. Pooled mean differences (MDs) and standard MDs (SMDs) with 95% confidence intervals (CIs) between the intervention and control groups were calculated using a random effects model. Results: We identified 69 trials and, after an assessment of relevance, eight trials, including a combined total of 213 subjects, were analyzed. Muscle stretching exercises were shown to significantly reduce arterial stiffness and improve vascular endothelial function (SMD: −1.00, 95% CI: −1.57 to −0.44, p = 0.0004; SMD: 1.15, 95% CI: 0.26 to 2.03, p = 0.01, respectively). Resting heart rate (HR) and diastolic blood pressure (DBP) decreased significantly after stretching exercise intervention (MD: −0.95 beats/min, 95% CI: −1.67 to −0.23 beats/min, p = 0.009; MD: −2.72 mm Hg, 95% CI: −4.01 to −1.43 mm Hg, p < 0.0001, respectively) Conclusions: Our analyses suggest that stretching exercises reduce arterial stiffness, HR, and DBP, and improve vascular endothelial function in middle-aged and older adults.

Stretching is Superior to Brisk Walking for Reducing Blood Pressure in People With High–Normal Blood Pressure or Stage I Hypertension

“…Waist circumference decreased more in the walking (108 [13] to 103 [10] cm) compared with the stretching (100 [15] to 100 [16] cm) group (group × time; P = .029). There was no change in body mass over time for either group (data not shown).…”

“…Our purpose was to compare walking and stretching exercise programs in people with moderately elevated blood pressure. A recent meta-analysis of stretching programs 13 indicates similar reduction in systolic blood pressure (ie, −3.9 mm Hg) but potentially higher reduction in diastolic blood pressure (ie, −2.7 mm Hg) compared with recent meta-analyses of walking programs (reduction in systolic blood pressure of −3.1 to −4.1 mm Hg and reduction in diastolic blood pressure of −1.5 to −1.8 mm Hg). [14][15][16] The only study to compare a stretching to a walking program (in sedentary pregnant women) found that stretching was superior for reducing blood pressure (systolic blood pressure of −4 mm Hg and diastolic blood pressure of −1 mm Hg) compared with walking (systolic blood pressure of +5 mm Hg and diastolic blood pressure of +4 mm Hg).…”

Effects of Different Long-Term Exercise Modalities on Tissue Stiffness

“…A growing body of evidence regarding the effects of stretching and vascular health is present. Two recent meta-analyses have investigated the effects of stretching on arterial stiffness [ 110 , 111 ]. The results of both investigations are based on a partial overlap of the included records; therefore, these present similar outcomes.…”

“…Both studies report a decrease in arterial stiffness as a consequence of stretching. The study of Kato et al [ 111 ] only included longitudinal interventions, while the study of Thomas et al [ 110 ] also included acute forms of exercise. The authors of this last investigation state that the moderator analysis regarding the length of the intervention did not highlight significant differences, which underpins that acute stretching bouts may also be able to decrease arterial stiffness, both central (carotid–femoral PWV) and systemic (brachial–ankle PWV).…”

Effect of an Acute Resistance Training Bout and Long-Term Resistance Training Program on Arterial Stiffness: A Systematic Review and Meta-Analysis

“…Future studies should find out to what extent RT parameters, stretching and aerobics affected AS. Recent meta-analyses demonstrated that stretching reduced AS, HR, and DBP and improved endothelial function, all of which are crucial parameters of arteriosclerosis in middle-aged and older adults [96]. Another important thing that cannot be neglected is the location of PWV measurement.…”