Calgary winters are bitter cold and blanketed with snow, and many of us are stricken with the daunting task of shoveling. We endure this task to keep our sidewalks safe and to avoid penalty from the City. While shoveling can be a great form of exercise for many, caution is advised. Here’s how to you keep yourself safe and injury free when shoveling.
It is important to remember that sedentary adults are at greater risk for heart attack and stroke when engaging in strenuous activities due to the sudden increase in heart rate and blood pressure. Shoveling snow can raise your heart rate to 97% of its maximum ability and systolic blood pressure to 200mmHg. Even walking in snow increases the demands of the heart and at-risk persons should slow their pace. Factors that place you at increased risk include: history of heart disease, high blood pressure, high cholesterol, smoking and sedentary lifestyle.
Clothing Considerations
Your body’s core temperature can drop quickly in cold weather unless you are wearing the right clothing to protect against hypothermia and frostbite. Clothing reduces heat loss through insulation by trapping air between layers. Recommended cold-weather clothing consists of three layers: an inner layer of lightweight polyester or polypropylene, a middle layer of polyester fleece or wool, and an outer layer designed to allow moisture transfer to the air while repelling wind and rain.
Synthetic fibers help wick away perspiration better than natural fibers such as cotton. However, you should adjust clothing insulation to minimize sweating and use clothing vents to reduce sweat accumulation.
An outer layer is only necessary if it is rainy or very windy and you should reduce clothing insulation as exercise intensity increases. Lastly, remember to wear a toque or hat to prevent heat loss from your head.
The risk of frostbite is less than 5% when the temperature is above -15°C (5°F), but increased safety precaution is warranted when the wind chill temperature falls below -27°C (-8°F). In these conditions, frostbite can occur in 30 minutes or less in exposed skin. In concert, whole-body and facial cooling lowers the threshold for the onset of angina (chest pain) during exercise. The type and intensity of exercise also modifies the risk for a person with cardiac disease. Activities that involve the upper body and cause an increase in heart rate are a potential risk.
Safety Tips
When you head outside this winter to shovel remember the following safety tips from Alberta Health Services to avoid injury and strain to your back and heart.
- Reduce your chance of injury by performing 5 minutes of light aerobic exercise, dynamic movements, and stretches before you shovel. An adequate warm-up prepares the muscles to be used.
- Shovel soon and frequently. Even light snowfalls can pile up quickly and freshly fallen snow is easier to remove than snow that’s been packed down. Shoveling frequently also lessens each lifting load and reduces back strain.
- Pace yourself and avoid over-exertion. Snow shoveling is strenuous physical activity, especially for those who are sedentary. Strenuous activities cause a quick rise in heart rate and blood pressure. If you experience any shortness of breath or pain in your chest, jaw, arm or back, stop immediately.
- Take breaks indoors every 15 minutes, especially if there’s been a heavy snowfall. Don’t try to clear the snow all at once.
- Push the snow instead of lifting it and don’t overload your shovel. Replace your conventional shovel with a snow pusher or a small blade shovel. A smaller shovel requires you to lift less snow at a time and reduces the strain on your body.
- Maintain an optimal posture when lifting snow by keeping your feet close together and knees slightly bent with your back straight. Your abdominal muscles should be tightened to help support your back.
- Avoid twisting or bending when you toss a shovel full of snow. Always throw it in front of you instead of behind you, to the side, or over your shoulder. Most back injuries occur when you are in a twisted position. If you need to move snow to one side, reposition your entire body to face the direction you are pushing.
- Keep the weight of the shovel close to your body and avoid extending your arms. This prevents excess strain on your back muscles and spine.
- Watch where you walk and move consciously to reduce your risk of falling. When working outside in slippery conditions wear low-heeled shoes or boots with non-skid soles. Also, try to keep extension cords out of the way and pets inside.
- Stay well hydrated and avoid stimulants such as caffeine and smoking. Stimulants can place strain on your heart by constricting blood vessels and increasing heart rate.
People with risk factors for heart attack or stroke should be cautious and consider using a snow blower or having a neighbour shovel their sidewalk. The incidence of fatal heart attacks increases after heavy snowfalls. Those with heart problems or previous heart attacks should consult their physician before engaging in strenuous activities such as snow shoveling. In addition, sedentary individuals should be careful.
The City of Calgary has snow removal programs for those unable to shovel their own sidewalks and driveways. If you are feeling neighbourly you can become a Snow Angel by adopting an older adult’s sidewalk this winter.