Regular Cannabis Use is Associated with a Diminished Anandamide Response to a Standard Exercise Stimulus: A Pilot...

The endocannabinoid system (ECS) is increasingly recognized as an important regulator of many physiological systems. People who use products derived from Cannabis sativa L. are exposed to exogenous cannabinoids. The influence of this exogenous exposure on the ECS is unclear. People who use cannabis have demonstrated lower basal levels of endocannabinoids, but the dynamic response of their ECS to a controlled stimulus is unknown. Our study purpose was to compare circulating concentrations of the endocannabinoid N-arachidonoylethanolamine (anandamide, AEA) and subjective experiences between people who use cannabis and those who do not, during and following a standardized exercise stimulus.

Twenty adults (n = 8 who regularly use cannabis [age: 21-32 years; 5/3 males/females] and n = 12 who do not use cannabis [age: 21-39 years; 7/5 males/females]) completed a 1-h treadmill run at an intensity equivalent to 65% of peak oxygen uptake. Arterialized-venous blood was collected prior to, during (including the last minute of exercise), and 15 min following exercise for determination of anandamide concentration. The subjective experiences of the participants during and after the run were assessed with responses to several questions assessed on a Likert scale.

Compared with controls, the cannabis use group had lower AEA concentrations at end-exercise (0.47 ± 0.13 vs. 0.33 ± 0.10 ng/mL; p = 0.015) and 15-min post-exercise (0.57 ± 0.17 vs. 0.38 ± 0.18 ng/mL; p = 0.001). The cannabis use group also had worse mood (3.25 ± 1.03 vs. 2.29 ± 1.34; main effect of condition p = 0.05) and higher probability of feeling pain (p < 0.001).

Habitual cannabis use was associated with diminished AEA response, worse mood, and more pain during/following exercise. These pilot data might have implications for clinical outcomes associated with cannabis use, including cannabis use disorder and withdrawal, as well as potentially for exercise adherence.