A study published in The Journal of Strength and Conditioning Research put the two forms of exercises to the test to see which one had the better effect on heart health.

The researchers wanted to see if aerobic exercise or resistance exercise produced different effects on the hearts of the volunteers, and how different heart biomarkers – vasodilation, heart rate and cardiac output – contribute to arterial distensibility, the flexibility and health of your arteries.

• Ten healthy men (not fat, not on medications, not sick, and with normal blood pressure) aged 21-29 volunteered to be lab rats.
• Baseline measures for strength were taken: 10 rep max for bench press, bent-over row, leg extension, leg curl, military press, biceps curl, close-grip bench press, and ab crunch.
• Baseline measures for cardiac health were also taken.

Cardio and weight-training days were randomly assigned and done 72 hours apart. Experiments were done 3 hours after eating. No strenuous exercise was done for 48 hours before the experiment days.

Cardio days consisted of the men doing the cycle ergometry protocol (a fancy way of testing VO2 peak) at 65% of their peak oxygen consumption. Weight days consisted of lifting 3 sets of their 10 rep max for each exercise with 90 seconds of rest.

Pulse Wave Velocity (PWV, a way of measuring arterial stiffness/flexibility) and beat-to-beat blood pressure were measured 40 and 60 minutes post exercise. Vasodilation – widening of blood vessels which equals lower blood pressure and healthier heart – was measured pre-workout and 1 hour afterward.

There was greater vasodilation 60 minutes after weightlifting than in cardio despite there being an increase in arterial stiffness after weightlifting. Basically, this means that blood pressure decreased after weightlifting and not 60 minutes after cardio.

Yes, there's still a time and place for cardio, but it seems that your heart loves lifting heavy shit just as much as you do. Even back in 2000, an expert panel organized by the American Heart Association found more similarities than differences between cardio and weightlifting, and even called for a revision in the then-current cardio-heavy recommendations for heart disease patients.

So, go on. Let that beanpole runner scoff at you and accuse you of being a dumb meathead. Now you know better.

1. Collier SR et al. Changes in Arterial Distensibility and Flow-Mediated Dilation after Acute Resistance vs. Aerobic Exercise. J Strength Cond Res. 2010 Oct;24(10):2846-52.
2. Volaklis KA et al. Resistance Training for People With Heart Disease. Harvard Health Letter 10 (2000): 5-6.