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Principles of Exercise

The 12 principles of exercise are akin to the 10 commandments (I think it's 10 isn't it?) Apply each of the principles to each of your clients and their progress is quite simply...guaranteed!

Personal Training Exercise Principles imageThe exercise principles outline the criteria that guide all training.  Each principle allows us to critique some element of a person’s training.  When a person’s training follows the principles well it is most likely to be successful.  Following is a list of the principles and their definitions (in lay terms as well so we don't get to 'fancy pants scientific'.




Technical Term

Layman’s term


Optimal benefits occur when programs meet the individuals needs & capacities of participants 

People are different and their exercise needs vary – a prescription must take this into account


Each person responds differently to the same training stimulus

Don’t expect that the same prescription will get you the same result with each person – you have to monitor and adapt training as you go to suit different clients


The training stimulus must be specific to the clients desired outcomes

Training must be specific to an individuals goals


For adaptation to occur the volume of exercise must overload the body in some way in line with the capacity of the individual to cope with that overload

You get improvements by doing a bit more

Progressive Overload:

For continual adaptation overload must be progressive, that is the dose of exercise must increase

Get improvements by  doing a bit more each time


For optimal adaptation and to avoid stagnation, overuse, and injury the exercise stimulus must be varied (this does not simply mean changing exercises all the time).

Change is as good as a holiday.  Variety allows recovery and can reduce injury risk


Optimal adaptation requires rest periods to be interspersed with training sessions sufficient that the adaptations caused by the exercise dose can take place.

Rest to get the best out of your exercise, not too long and not too little.


All beneficial effects of exercise are reversible if exercise ceases

Use it or lose it.


Current fitness levels can be maintained by exercising at the same intensity while reducing volume (frequency and/or duration) by 1/3 to 2/3

It’s easier to keep fitness than to create it.  Train as hard, stay regular but shorten workouts to maintain a fitness component


As fitness increases the relative & absolute improvements in fitness will decrease, even with continual overload

Genetics play a part.  There is a law of diminishing returns with exercise.  Unfit people will change a lot early on, then less and less despite continuing to train hard.


When training several components at once (e.g. strength & endurance) the stimuli may interfere with each other, thereby slowing adaptation in one or both components

You can’t have it all at once.  As all systems are related fatigue in one will interfere with the results of training in another.


Each of the fitness components has an ideal training frequency (how often), intensity (how hard), time (duration, rest intervals) and type of exercise to be used.  The ‘FITT’ principle is largely a practical ‘amalgamation’ of all the other exercise principles

In order to achieve the desired outcome the training must ‘FITT’ the component you wish to improve

How do the principles of exercise apply to individuals training in a fitness club?


One of the easiest ways to see how the principles apply is to discuss what happens when you don’t apply them properly.  This table covers some basics using examples you are more than likely to encounter at some stage in a fitness club.



Client Example



Sue and Sally are both doing a group fitness class with weights for the first time.  Sue is getting a sore back, while Sally is getting sore calves.  They both seem to be doing the exercises in the same way and at pretty similar weights.

Sue and Sally are different so they are responding differently to the same exercises. 


Tim is getting really big lifting weights on a split programme four days a week whereas his training partner Jim is losing size!

Tim and Jim have different responses to the training.  Jim needs to review the FITT being used for him


John has been using group fitness ‘step’ classes a lot to get ready for his cycling race coming up soon.  However, his cycling times are not improving.

John needs to train more specifically.  In order to improve his cycling he must cycle enough to get the adaptations he desires.


Jenny is struggling to walk for two days after a heavy weight training session and long spin class that she took back to back

Jenny over-reached.  The volume of overload needs to match her capabilities – ease up girlfriend!

Progressive Overload:

Mary made some great gains initially when she started lifting weights.  She’s complaining now that weight training doesn’t work.  She hasn’t increased her weights for the last 3 months

Mary needs to work harder (more weights on her bar) as she has adapted to the loads she has on her bar long ago, now there simply isn’t enough weight to cause an adaptation.


Jane is doing Step classes five days a week because she loves it!  But she is starting to get sore shins.

Jane would be better to have a more varied exercise schedule so her legs get a rest from the repetitive stepping movement.


Deborah goes to the gym everyday and always goes hard at it.  Lately her weights are getting lower, she’s struggling to keep up in class and her body is always sore.

Deborah needs some rest between sessions or even some easy sessions or sessions that focus on different parts of her body.  That way her body has enough time to adapt before she trains again.


Tim is gutted.  He’s worked for six months to get into the police but since his ankle injury four weeks ago his running fitness has gone back to what it was some time ago.

Tim should have done some exercise on his legs (such as cycling/spin) to maintain as much of his fitness as possible while he recovered from his ankle injury.  This would have prevented some of the ‘reversing’ of his fitness.


Amanda is stoked.  Her fitness is just as good as when she went on holiday and all she did was 2 x 30minute hard runs each week.  Before she left she was running 4 x a week for between 40-60 minutes

Amanda got it right.  She kept up the exercise, particularly the intensity, and was able to maintain her fitness even though she greatly reduced her total training time.


Chris is a world class kayaker but over the last two years his times have only dropped by 3% despite his huge efforts in training.  He has moved from 30th to 18th in the world on the back of this small change.

Chris is experiencing the ceiling affect in that his genetics, the type of training he uses and the amount of fitness he already has are all meaning he can only get small gains from large volumes of training now.  He may want to trial different approaches to see what will help most.


Liz is doing three spin classes, two pump classes (weight training group fitness classes) and a five day split routine to get into shape for body sculpting.  The challenge is her muscles aren’t growing so she still looks a little out of balance.

Liz is getting interference.  She is training across so many things at once her body is not sure whether to put muscle on or strip it off.  Liz needs to prioritise to build lean muscle and keep her spin to a class or two only and probably drop pump all together.  She could put in some yoga to help with flexibility and recovery as an alternative.


Ben has been weight training regularly for 3 years.  He wants to gain size in his upper body.  He does bench press and bicep curls 5 times a week, for 4 sets of 4-6 repetitions in each set

Ben hasn’t got the right ‘FITT’ for hypertrophy training – the reps are too low, the load is probably to high and he’s training the same muscle groups to frequently.  He needs to restructure his program – increase repetitions, perform his bench press and bicep curls a maximum of two days per week, and incorporate alternative exercise using back and tricep muscles on alternate days from his bench and bicep days.


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