In my last blog, I talked about the importance of exercise. You may be wondering how much exercise you should aim for and how hard you should push yourself.
The Physical Activity Guidelines for Canadians recommend at least 150 minutes of moderate-intensity cardio activity per week or 75 minutes of vigorous-intensity activity. You can also combine moderate and vigorous activity. For example, simply walking briskly 5 days a week for 30 minutes will help you meet the target.
In addition to cardio, studies suggest a minimum of two 20-minute strength training sessions per week. Strength training can involve going to a gym and using machines or lifting weights. For those who don’t wish to join a gym, a set of dumbbells at home is a convenient solution. Resistance bands and bodyweight exercises, such as push-ups, also count as strength training. Maintaining muscle strength is especially important as we age, as we can lose 6-8 pounds of muscle per decade after the age of 60. For seniors, strength training is crucial for fall prevention. Retaining arm or grip strength can help prevent fractures or dislocations if you stumble or lose your balance. It can also help protect your spine if you are able to grab onto a handrail or piece of furniture.
So, what does moderate and vigorous cardio activity mean?
Moderate exercise intensity is 50%-70% of your maximum heart rate, while vigorous exercise is 70%-85%. To calculate your maximum heart rate, multiply your age by 0.7 and subtract that total from 208. Next, calculate your resting heart rate by counting how many times your heart beats per minute at rest (typically between 60-100 beats per minute for adults). To establish your heart rate reserve (HRR), subtract your resting heart rate from your maximum heart rate. Now, multiply the HRR by 0.5 to 0.7 for moderate exercise and by 0.7 to 0.85 for vigorous activity.
To measure your heart rate during exercise, use a smart watch or another wearable heart rate monitor. Alternatively, you can take your own heartrate by counting the beats from the artery on the side of your neck for 15 seconds and then multiplying that number by 4.
For a more informal calculation, if you can say four or five words between breaths while walking, biking, or running, your heart rate is likely in the 110-130 range.
If you’re not fit or are just starting an exercise program, aim for the lower end of your target heart rate zone and slowly build up the intensity over time.