Research

Hormonal

Both aerobic and resistance training significantly increase plasma fibrinogen levels in middle-aged, android-obese men, which is a paradoxical increase in a known cardiovascular risk factor.

Be aware that short-term exercise training might temporarily increase fibrinogen, a blood clotting factor. This does not negate the benefits of exercise but suggests monitoring may be needed in high-risk individuals.

ModerateRefutesMEDIUM confidence
there was a surprising 22%-25% increase in fibrinogen after 10 weeks of exercise in both groups
William J. Banz et al. · Experimental Biology and Medicine · 2003

Why this rating

Randomized trial, small sample size, short duration.

Source

Effects of Resistance versus Aerobic Training on Coronary Artery Disease Risk Factors

William J. Banz et al. · Experimental Biology and Medicine · 2003

DOI 10.1177/153537020322800414

rct · n=26Cited 233×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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