Many Long Islanders used Friday to dig out from Thursday's blizzard that blanketed both Nassau and Suffolk counties. 

Those who waited until Friday found that the snow was a bit heavier and more compact. 

Medical professionals say shoveling in such cold weather could increase the risk of a heart attack. 

SNOW TOTALS AND WIND REPORTS: National Weather Service

"Cold air causes constriction of the blood vessels. That coupled with the strenuous nature of the shoveling, it could cause less blood flow to the heart muscle that could create the scenario for a heart attack," said Wendy Beckmann, of NYU Langone Huntington Medical Group. Beckmann is a a nurse practitioner board certified in cardiology.

Those using snowblowers are also being urged by officials to never use hands to clear debris.