Post Activation Potentiation, Overcoming Isometrics: How to unlock extra results from your training

When it comes to motorsport as drivers or riders there is always a desire to find every last tenth of a second in performance. There is a drive and desire to maximise the performance from the car or bike and to optimise every single component in the race to not just win but be champion. That same ethos and drive should be no different in the physical preparation to compete. 

When it comes to training and physical preparation as an athlete simply turning up is just the first step. The composition of the training, the tools and methods used are like the set up of the car or bike, fine tuned, tweaked and adjusted to suit each individual to deliver the best result. One frequently under valued tool in the chest when it comes to training is the use of post activation potentiation (PAP) and overcoming isometrics. 

When it comes to enhancing strength, power and performance PAP can be the golden key. There is plenty of research that highlights the benefits it brings and how it is one of the most effective mechanisms to maximise power output, power, speed, motor unit recruitment both during training sessions and competition. 

So what is PAP? Well this bit will get a bit scientific….

In the simplest form PAP is the process by which heavy isotonic movements (back squats, deadlifts, bench press…) that require intense voluntary muscular contractions produce a physiological phenomenon that increases power and peak force in following explosive movements.

So what is the physiology behind PAP? 

While there is still some debate on the exact physiological process that produces PAP there are some strong theories around it. 

The first being that the heavy resistance movement increases phosphorylation of the Myosin Light Chains (MLC) through Myosin Light Kinase, this renders the actin-myosin myofilaments more sensitive to Ca2+ that is released from the sarcoplasmic reticulum. The phosphorylation of the MLC then increases the actin-myosin cross bridging in turn then increases the force in subsequent contractions.

The second theory being the heavy resistance movement increases motor neurone excitability. This could be caused by an increase in motor unit recruitment along side potential increased synchronisation of motor unit recruitment, a decrease in pre-synaptic inhibition and greater central input from the nervous system to the motor neurons.

Whether one or both of these theories occur or the extent to which both contribute to PAP is still to be settled, what is evident is the increase in power and force that is displayed.

What then is overcoming isometrics? 

While most studies around PAP have looked at isotonic exercises utilising free weights and heavy loads recently more and more research has started to look at the use of overcoming isometrics. Essentially pushing or pulling against an immovable object to create huge amounts of muscular activation with the aim of producing the same effects as PAP.

In most of these studies the results have even shown that when it comes to producing PAP, overcoming isometrics are superior to the traditional isotonic movements. 

The physiological processes and mechanisms that lead to the superior PAP from overcoming isometrics are yet to be understood. However there is an initial theory that carries some credibility.

It is hypothesised that the maximal voluntary contraction created in an overcoming isometric action, although lasting generally less than a few seconds allows for the gradual ramping up of both motor unit recruitment and firing frequency. Or in basic terms with each second of isometric contraction we get more and more motor unit activation until we hit near maximum levels.

The added bonus is that there is current thought the use of isometric contractions could have a permanent lasting effect of improving an individuals ability to recruit higher threshold motor units during normal isotonic movements.

The research currently points towards further benefits with an increase in neuromuscular efficiency and the high levels of intramuscular tension produced being an incredibly strong stimulus for muscle strength and hypertrophy gains. 

Right that’s the science / physiology heavy bit done so if you’re scrolling through looking for the practical applications the next bit is for you.

The importance of rest periods when looking to elicit PAP 

Whether using isotonic contractions or overcoming isometrics the rest period between the heavy resistance movement or isometric and the power based movement is key. Both the isotonic contractions and overcoming isometrics will produce large levels of fatigue. 

For the isotonic movements this will be peripheral fatigue in the muscles and motor units being worked, whereas for the overcoming isometrics this will present as central nervous system fatigue. 

In both instances to be able to create the most power and greatest PAP we need to reduce some of the fatigue so it doesn’t outweigh the potentiation response. While the ideal protocols for this are at the end, in general the stronger you are the more time will be needed for the fatigue to dissipate. 

However having too much rest can cause the PAP response to gradually diminish. 

For each individual the ideal rest will vary and there is a large amount of inter-individual variation so some trial and error will be needed to find the optimal rest period.

How can this help enhance training for motorsport? 

When it comes to the rider and driver, ultimately we are always looking to get the most bang for buck from training. This means looking to find the most efficient way to deliver a result with the minimum effective dose. 

We know that both driving the car and riding a bike competitively require significant strength and power components, traits that we need to develop in the gym to allow the athlete to perform at their best.

When looking to develop strength and power the inclusion of PAP or overcoming isometrics can allow us to create more force, power and to work at a higher intensity in the subsequent sets. This can have a big impact on enhancing the strength and muscular hypertrophy development depending on the training goals. 

The use of PAP and overcoming isometrics within the training will bring additional benefits as mentioned above that will carry over into sporting movements and competition such as an enhanced ability to recruit higher threshold motor units and enhancing power production. 

With isotonic movements and particular those with a controlled eccentric portion can also see an increase in proprioception in athlete and a better feedback systems for proprioception within the body which can help to enhance form, biomechanics and movement. 

The final benefit worth noting is that utilising PAP and or overcoming isometrics within training allows us to work at increased intensities in the subsequent movement patterns and with enhanced force and power while reducing the fatigue on either the central nervous system or peripheral fatigue within the muscles depending on the method used. 

(Traditional isotonic movements will create less fatigue for the central nervous system but generate greater peripheral fatigue in the muscles, in part this is through the build up of lactic acid. Overcoming isometrics on the other hand produce very little peripheral fatigue but will place a greater strain on the central nervous system.

So what are the optimal loading, dosing and rest recommendations for PAP and overcoming isometrics? 

When it comes to both isotonic movements and overcoming isometrics there are some well established protocols in the research literature on dosing and loading to achieve the optimal PAP. 

For isotonic movements the general consensus across the literature is that 3 sets of 3 reps with a loading of 60-85% of your 1RM for a movement followed by 7-8 minutes of rest will be optimal to induce PAP. 

When it comes to Isometric contractions the optimal dosing from literature appears to be 3 sets or 3-4 repetitions using a 3-5 second maximal effort isometric contraction. Again, while rest in research ranges from 2-10 minutes the optimal appears to be in the range of 7 minutes. 

When it comes to overcoming isometrics with the high strain these place on the central nervous system and the fatigue it can create, dosing over a week is a big consideration. From the research at present the optimal loading frequency is once per week per muscle or lift and no more than 3 sets per muscle group. Increasing beyond this can result in symptoms of overtraining.