A winter storm with a fine dividing line moved through western Massachusetts Sunday night. Residents woke up to varying conditions across the Pioneer Valley. The north saw at least 6 inches of heavy snow, while the Springfield area only saw an inch or two of slush.

Nonetheless, last night's storm was heavy, both in the intensity of rain and snow, as well as the type of snow it left behind. Doctors know heavy snow can be like heavy weights, injuring someone who is not in shape.

"They haven't exercised for two or three months, or ever, and they go out and shovel snow on a day like today where the snow is very wet." said Dr. Robert Hansen, attending emergency physician at Wing Memorial Hospital in Palmer. "They think they can just go out there and do it like they've been doing it every day."

Some snow shovels do not follow the motto "lift with your legs, not with your back." As a result, Dr. Hansen says upper body injuries due to shoveling are the most common, especially the shoulders and back.

Another problem is the snow blower. Heavy wet snow can clog the blades, making it dangerous when it appears to be powered down.

"The engine still has a lot of torque built up." explained Dr. Hansen. "As soon as you remove the obstruction, that torque is going to propel the blade forward and anything that's in the way is going to get snipped right off."

The reason for this heavy, slushy, packing snow is because of its main ingredient - water. In the case of Sunday night's storm, too much water.

On average, ten inches of snow is created from one inch of water, something known by meteorologists as the 10-to-1 ratio. But this number can vary depending on the snow type. It may take 25 inches of fluffy, powdery snow to get that inch of liquid water. A wet, heavy snow like Sunday night's will have more water content, and only five inches of snow may be required to squeeze out an inch of water. All of that water means more weight and more hazardous shoveling.

"Try to take a full shovel of that stuff and you're going to end up visiting us." said Dr. Hansen. "Do half a shovel-full, a quarter shovel-full, something you can easily manage without putting too much strain on yourself."