The Acute Cardiovascular Response to Dynamic Exercise and Recovery Following Cannabis Use

Despite clear benefits in the long term, exercise transiently increases cardiovascular risk during and immediately after exertion. Cannabis use has similarly been associated with cardiovascular events, but its effects on cardiovascular function and potential interaction with exercise remain poorly understood. We examined cardiovascular responses during and after exercise following cannabis use, to elucidate their combined effects. In a within-subject design, participants either inhaled cannabis with a high THC content via smoking (S-THC) or vaporizing (V-THC), or vaporized cannabis with a high CBD content (V-CBD). Cardiovascular effects of cannabis were assessed through measures of arterial stiffness, endothelial function, and cardiac function performed at rest and following 20-minutes of maximal exercise (n=14). Exercising cardiac function was evaluated separately using stress echocardiography (n=22). Blood pressure was assessed before, during, and after the 20-minute maximal cycling test. Smoking THC-predominant cannabis elevated post-exercise pulse pressure (Pre vs. Post; Control: 42±6 vs. 41±7mmHg, S-THC: 43±4 vs. 50±9mmHg, V-THC: 44±5 vs. 46±8mmHg, V-CBD: 43±4 vs. 43±7mmHg; p<0.01). The effect of exercise on arterial stiffness and endothelial function was not modified by cannabis; however, septal isovolumic contraction time (Baseline: 72±19ms, Control: 76±20ms, S-THC: 60±11ms, V-THC: 66±12ms, V-CBD: 69±16ms; p=0.01) was reduced in S-THC compared to after control exercise (p=0.048), indicating altered systolic function. Blood pressure during maximal cycling was similar regardless of exposure. Systolic function, diastolic function, and ventricular mechanics during exercise were unaffected by cannabis. THC-predominant cannabis increases pulse pressure and alters cardiac, but not vascular, function after exercise. Cannabis does not affect blood pressure or cardiac function during exercise. These findings demonstrate the nuanced effects of combining cannabis use and exercise on cardiovascular physiology.