Metformin altered blood pressure and aortic waveform adaptations in relation to inflammation following exercise training in adults at risk for metabolic syndrome.
Key Findings
Results
HiEx+Met reduced fasting peripheral diastolic blood pressure compared to other treatment groups.
Participants were randomized to four groups: LoEx+PL (n=22), LoEx+Met (n=21), HiEx+PL (n=24), and HiEx+Met (n=24)
The trial was double-blind and placebo-controlled over 16 weeks
High intensity exercise was conducted at ~85% VO2max 5 days/week
Results
All treatments except HiEx+Met increased fasting central pulse pressure.
LoEx+PL, LoEx+Met, and HiEx+PL all increased fasting central pulse pressure (p < 0.05)
HiEx+Met did not increase fasting central pulse pressure
Central blood pressures were assessed via applanation tonometry during a euglycemic-hyperinsulinemic clamp
Results
Low intensity exercise plus placebo tended to decrease carotid-femoral pulse wave velocity (cfPWV), a measure of arterial stiffness.
LoEx+PL tended to decrease cfPWV (p = 0.051)
cfPWV was assessed to determine arterial stiffness
Low intensity exercise was conducted at ~55% VO2max 5 days/week for 16 weeks
Results
Upon insulin-stimulation, peripheral diastolic blood pressure and reflection magnitude increased while pulse pressure amplification decreased after metformin treatments compared with placebo treatments, independent of exercise intensity.
pDBP and reflection magnitude increased after LoEx+Met and HiEx+Met compared with LoEx+PL and HiEx+PL (all p < 0.05)
Pulse pressure amplification (PPA) decreased after LoEx+Met and HiEx+Met compared with LoEx+PL and HiEx+PL (all p < 0.05)
These effects were independent of exercise intensity
Insulin stimulation was assessed using a 120 min euglycemic-hyperinsulinemic clamp (40 mU/m²/min, 90 mg/dL)
Results
Fasting MMP-1 was significantly higher and MMP-7 tended to be higher after metformin treatment compared with placebo, independent of exercise intensity.
Fasting MMP-1 was higher after Met compared with PL (p < 0.05)
Fasting MMP-7 tended to be higher after Met compared with PL (p = 0.063)
These effects were independent of exercise intensity
Inflammatory measures assessed included hs-CRP, IL-8, MMP-1, and MMP-7
Methods
The study employed a 16-week double-blind, placebo-controlled trial design with four arms combining two exercise intensities and metformin or placebo.
Metformin dose was 2000 mg/day
Low intensity exercise was ~55% VO2max 5 days/week; high intensity exercise was ~85% VO2max 5 days/week
Fitness was assessed by VO2max and body composition by DXA
Trial registration: NCT03355469
Total sample size was 91 participants (LoEx+PL n=22, LoEx+Met n=21, HiEx+PL n=24, HiEx+Met n=24)
Malin S, Heiston E, Battillo D, Ragland T, Shah A, Patrie J. (2026). Metformin Alters Exercise Training Induced Blood Pressure and Aortic Waveform Adaptations in Adults at Risk for Metabolic Syndrome.. Journal of clinical hypertension (Greenwich, Conn.). https://doi.org/10.1111/jch.70215