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Your Fitness Training Programme… What Are You Missing? Part 3: Intensity

We are going to break down and explore in detail:

  1. Volume
  2. Frequency
  3. Intensity
  4. Rest Periods & Tempos


Training Intensity

Training intensity refers to either:

  1. How much you are lifting – the intensity of load
  2. How close you are lifting to your maximum effort – intensity effort


There are different ways of measuring the intensity of load. 

Percentage of 1 Rep Max (1RM)

  • 1RM = the greatest amount of weight that can be lifted for 1 rep, with proper technique. 
  • Written as a % of the maximum load 



If your 1RM for a back squat is 75kg. 

50% of this 1RM = 37.5kg 

75% of this 1RM = 56.25kg 

You can change the intensity you are working at by changing the % of the maximum load that you work with. 

You could opt for a higher % but lower reps, or a lower % and higher reps. 

The Brzycki formula can be used to calculate the appropriate amount of weight someone should lift based on their max reps at a certain weight. 

% 1RM Number of Reps 
100 1
95 2
90 3-4
85 5-6
80 7-8
75 9-10
70 11-12

Repetition (reps) Maximum

  • Refers to the greatest amount of weight a person can lift ‘X’ number of times e.g. the maximum weight that can be lifted for a specific number of reps (10RM/3RM etc) 
  • This assumes that maximal effort is given to perform the reps e.g. if you perform 10 reps at 40kg but could have performed 2 more reps, this is not your true 10RM. 



  • Is it safe to perform a 1RM test? Is it appropriate for the exercise? Have you got safety measures in place in case you cannot complete the lift e.g. safety bars/spotter?
  • These values above are an estimate. Just because the formula says you should be able to lift a certain weight for a certain amount of reps, doesn’t mean this is the case! 
  • The above table is showing what is possible for a single set. When performing multiple sets, fatigue is a factor and may influence the amount that can be lifted. 
  • It is a totally different skill to lift for a 1RM compared to a 10RM. It is not advisable for beginners to try 1RM testing until they have solidified the technique. 


There are also different ways of measuring effort.

Rate of Perceived Exertion (RPE)

  • ‘On a scale of 1-10, how did that feel?’ might be a question your trainer has asked you before and it can be hard to answer initially, but this is a scale that measures subjective effort, difficulty and fatigue during an exercise. 
  • 1 represents minimal effort, difficulty and fatigue
  • 10 represents maximal effort, difficulty and fatigue and would show a rep max has been achieved. 
  • Tuchscherer developed a resistance training specific RPE scale – Reps In Reserve (RIR). 
  • This can be shown by saying 10 reps at 40kg was RIR 2 (like the above example). This means 2 more reps could have been achieved. 
  • RPE/RIR can take into consideration the inherent variation we have in performance due to external factors such as sleep and nutrition quality, stress levels, volume across the week. 



  • These scales are subjective and it puts the ownership on the client to know what intensity they are working at.
  • It takes time to understand what true muscular failure feels like, so beginners especially will struggle with getting these scales correct.
  • It can be difficult to apply to new exercises when there is no comparison of how it has felt before.
  • RPE/RIR scales should not be used as the sole intensity descriptor because of these reasons, but are a good method to assign and adjust training intensity based on how something is feeling on a given day. 
  • Successful application of these scales requires familiarisation of concept and exercise, experience and honesty with oneself. 


Make sure you have read Part 1: Volume & Part 2: Frequency, and if you have any questions about your training please ask your trainer.

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