Neck Static Stretching Acutely Reduces Blood Pressure Through Reduction of Tissue Stiffness: A Randomized Crossover Trial
Phase: NA
Conditions: Healthy, Healthy Participants, Healthy Subjects, Healthy Volunteers, Stretching, Stretch, Static Stretching
Sponsor: University of Palermo

Neck static stretching acutely reduces blood pressure through reduction of tissue stiffness: A 
randomized crossover trial 
 
 
 
 
NCT Number: NCT07197047 
 
Document Date: 07/10/2025 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Study Protocol 
This study hypothesised that static stretching (SS) of the right posterolateral cervical region would elicit a 
reduction in blood pressure (BP), potentially mediated by specific physiological mechanisms. Accordingly, 
the aim of this study was to investigate the acute effects of SS of the posterolateral neck region on BP and to 
explore the potential moderating roles of tissue hardness (TH) and heart rate variability (HRV). Twenty-five 
healthy participants were enrolled in a randomised crossover design. Each participant completed two 
experimental conditions: a SS session (SS) and a control condition (CC). The order of conditions was 
randomly determined using the website www.randomizer.org. During each visit, measurements were 
obtained at two time points: baseline (T0, upon arrival) and immediately after the assigned condition (T1). At 
each assessment point, outcomes were collected in a standardised sequence: BP was measured first, followed 
by bilateral assessments of TH adjacent to the seventh cervical vertebra (C7), and subsequently by recordings 
of HRV and heart rate (HR). Between T0 and T1, participants either performed the static stretching protocol 
(SS) or completed a 6-minute seated rest period (CC), with the duration of the control period matched to that 
of the stretching intervention. 
 
Statistical Analysis Plan (SAP) 
Data will be expressed as means ± standard deviations. Baseline comparisons between conditions (SS vs. 
CC) will be assessed using paired t-tests for all variables. To evaluate the effects of time (T0 Vs. T1) and 
condition (SS Vs. CC), a repeated-measures ANOVA (2 × 2 design) will be performed. When significant 
time × condition interactions are identified, post hoc analyses with Scheffé adjustments will be conducted to 
determine specific within- and between-condition differences. Effect sizes (ES) will be calculated for all 
primary analyses, with partial eta squared (η²ₚ) used as the index of ES. The magnitude of effects will be 
interpreted as small (0.01–0.059), moderate (0.06–0.139), or large (≥0.14). All statistical analyses will be 
performed using Jamovi software (version 2.6.13.0; The Jamovi Project, 2025; https://www.jamovi.org), 
with statistical significance set at p < 0.05.