Reliability of non‐invasive blood pressure measurement during heavy resistance exercise: A pilot study

It is largely unknown how much heavy resistance exercise induces an acute increase in systolic blood pressure (SBP) and whether such increase can be measured in a reliable manner with non‐invasive equipment. We aimed to investigate test‐retest (day‐to‐day) reproducibility of acute SBP response during heavy resistance exercise using a non‐invasive methodology (Nexfin), which provides continuous hemodynamics in real time. Blood pressure was measured in 10 lean, healthy men (mean age 38 years.) during 3 × 8 repetition maximum leg press machine performance on two different days 48 hours apart. Systematic differences in SBP between day 1 and day 2 were analyzed by paired t test. A correlation analysis using Pearson's product‐moment determined the strength of the relationship of SBP between test days. No systematic bias between test days was found for SBP (day 1; 206 ± 19 vs day 2; 203 ± 20, P = .34). There was a significant correlation between measurements recorded SBP on test day 1 and day 2 (r = .88, P < .001). Limits of agreement were acceptable (upper 15.1 vs lower −21.0), and within‐subject SBP variation was 3.2%. Findings suggest a non‐invasive blood pressure device being reliable in measuring SBP pressure from day‐to‐day in lean, healthy men during heavy resistance exercise.