I just had to post this from the Kenosha News.
They have provided this nifty chart(double click on photo to enlarge):
Just in case you were not sure, the Kenosha News provides us with this nifty piece of advice on shoveling:
Stop immediately if you feel signs of a heart attack or stroke
Really folks, that is good advice.
Let me just add to this nifty advice:
Stop immediately if you feel signs of a heart attack or stroke AND SEEK MEDICAL ATTENTION PRONTO!