Cold constricts blood vessels, increasing blood pressure. Combine that with the fact that shoveling is mostly strenuous on your arm muscles —- where upper body

Cold constricts blood vessels, increasing blood pressure. Combine that with the fact that shoveling is mostly strenuous on your arm muscles —- where upper body exercise causes an increased HR and BP as compared to lower body exercise [0]. [0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4183232/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4183232/