This is the amount of effort required to perform a certain type of exercise. There are many ways to assess exercise intensity from the simple (the Talk Test) to the scientific (calculating VO2 max)
In simple terms how easy is it to talk during exercise?
Light intensity means you would be able to carry out a normal conversation or even sing during exercise
Moderate intensity means you are able to talk during exercise but would struggle with a full conversation. You would not be able to sing
Vigorous intensity means being unable to say more than a few words
Resting Heart Rate
Here you need to check your heart rate first thing in the morning or in the evening whilst sitting down resting and without having consumed alcohol or caffeine.
We recommend checking your heart rate at the wrist. You should be able to feel the radial artery at the wrist below the base of your thumb. Place the tips of your index and middle fingers (not your thumb) over the artery and press lightly. Take a full 60 seconds (timed using a watch) to count the heart beats. For an otherwise healthy 50 year old the rate should be somewhere between 60 and 100 beats per minute.
Light intensity means increasing your heart rate 30% above the resting value
Moderate intensity means increasing your heart rate 60% above the resting value
Vigorous intensity means increasing your heart arte 90% above the resting value
The Borg Rating Scale of Perceived Exertion
The Borg Rating Scale of Perceived Exertion is a questionnaire which you can ask yourself. It asks you to rate how hard the exercise is. It is rated between 6 and 20 as in the table below. You are looking to rate the exercise in the 12 to 16 range for moderate intensity.
This is the maximum capacity of the body to use oxygen and provides an assessment of physical fitness. It is expressed either as the rate in litres of oxygen being used per minute (l/min) or as a relative rate of millilitres of oxygen per kilogram of bodyweight each minute (ml/kg/min).
To calculate exercise intensity work out the maximal heart rate target which = 220 minus your age (in years)
For a 40 year old
Maximal Heart Rate is 220-40 = 180 beats per minute
Moderate Intensity exercise is 50% (range 40-60%) of VO2 max and the heart rate rise required to achieve this is 50-70% of the maximal heart rate.
So, for a 40 year old to achieve Moderate Intensity Exercise
Max Heart Rate = 180
50-70% of Max Heart Rate = 90-126 beats per minute
Obviously this depends a bit on the resting heart rate (the slower the resting heart rate the slower will be the heart rate at moderate intensity)
Our aim at Excarbs.com is to help people with diabetes using insulin to feel comfortable with taking up exercise – our advice is not aimed at elite athletes but hopefully covers the basic rules for most people living with diabetes.
Remember that if exercise is sustained you will become much more sensitive to the effect of insulin and the dose needed will fall which is a really good result!