The Perceived Exertion Scale is a chart you can use to estimate how hard you are exerting your body when working out. When determining your exertion level using the Borg Perceived Exertion Scale, you have to take into consideration your:
• heart rate • breathing rate • amount of sweating • muscle fatigue • in general, how tired you “feel” during your physical activity
To explain the Borg scale in more detail, at the bottom of the scale – 6 – no exertion takes place; at the top of the scale – 20 – maximum effort is taking place.
If you perform aerobic exercises, your goal is to be somewhere in between; most people try to be in the 12 to 14 range with 13 being “somewhat hard, i.e. you are feeling tired, but you can continue.”
If you walk, then your perceived exertion level would be more around a 9 to 11 – “walking at a comfortable pace.” Run sprints and you are more around a level of 18 to 19 – “you cannot continue that pace for very long.”
Measurement of Exertion
The measurement of exertion is a very individualistic thing and can vary among people doing the same activity at the same pace. For example, if you have an exercise partner not in as good of shape as you, she may perceive a higher level of exertion than you.
While perceived exertion levels are somewhat subjective, when combined with the talk test (also subjective) and your target heart rate (objective, as it is something you can measure by taking your pulse), you have a fairly accurate perception of your exertion level.
From there, you can adjust it as necessary according to your fitness goal or at least your desired result from that specific activity at that point in time. The point being your perceived exertion level can vary according to the activity you are performing.
The Talk Test
If you are not familiar with the talk test and target heart rate, here is a definition of each:
Talk Test – You can determine your level of physical activity by how many words you can say when talking while exercising. If you are at a high vigorous level, you should only be able to say a few words at a time.
Target heart rate – When working out, you should stay in the 80% to 90% of your maximum heart rate. To find your target heart rate, take 220 minus your age. Then multiply that figure by 80% or 90%. Monitor your heart rate and try to keep it at this level while exercising.
As a point of interest, Borg, the creator of the Perceived Exertion Scale, found that by adding a “0” to your perceived exertion scale figure, it was close to your desired target heart rate.
“A high correlation exists between a person’s perceived exertion rating times 10 and the actual heart rate during physical activity; so a person’s exertion rating may provide a fairly good estimate of the actual heart rate during activity.” (Borg, 1998)
By knowing your target heart rate, you could use this as a cross-check to see if you are accurately measuring your perceived exertion level.