Enhancing Athletic Performance with PAP

CHAPTER ONE – INTRODUCTION

1.1 Introduction

The need for stronger athletes has been driven by the high level of opposition faced in the competition (Harwood et al., 2015). Athletes at professional and even amateur level are exposed to evidence-based training methods which can enhance their performance, leading to the potential to compete at high or even elite level (Rønnestad, et al., 2015). Therefore, the understanding of evidence-based training methods to increase strength and performance for athletes is crucial. One such training strategies that has been used to try and improve performance is post-activation potentiation (PAP) (Sasaki et al., 2012). PAP is the phenomenon that is distinguished by acute facilitation of muscular enhancement in response to a loading stimulus (Bergmann et al., 2013). It has been utilised by athletes as well as coaches to promote performance with the use of loading protocols prior to carrying out a training exercise. This training exercise or test is said to be improved due to the prior loading stimulus applied to the body (Chen et al. 2013). It is said that PAP occurs because of the increase in phosphorylation of myosin regulatory light chains. This is down to the actin-activated ATPase being promoted and influence myosin solubility by supporting formation of the filament which leaves an increased sensitivity to myoplasmic calcium (Fukutani et al., 2014). Nevertheless, another way which is believed to be a driving factor in PAP is the increased enhancement of motor neurons. This enhancement causes higher recruitment of fast twitch muscle fibres because of the increased force and stress on the muscle. The fibre membranes experience excitation and contraction coupling through the transverse tubular system which produces Calcium ions release inside the sarcoplasmic reticulum. Troponin is now binding the actin filaments and the myosin heads create connections between the actin filaments and the myosin which allows the process of muscle contraction (Haldeman et al., 2014). For post-activation potentiation to occur, a loading stimulus must be applied. This loading stimulus can come in the form of a complex lifting protocol such as three to four sets of 3 to 4 repetitions of an exercise that requires whole body movement such as a back squat whilst lifting at least 5RM or 80% of 1RM (Talpey et al., 2014). After a complex lifting protocol, a rest period must be applied before testing and research show that between 7-10 minutes rest is the optimum time to produce significant results. Testing before 7 minutes and after ten minutes showed a decrease in performance compared to the optimum rest time (Gouvêa et al., 2014). A relevant testing exercise is used to measure performance when carrying out PAP. Exercises such as the countermovement jump, 10 or 30 second Wingate Anaerobic Test (WAnT), Sprints or standing jump have been used (Byrne et al., 2014). These exercises provide quantitive data in order to validate the potentiation exercise however, subjects with a comprehensive training background which includes strength training should be selected as participants so as to avoid high levels of fatigue whilst producing correct lifting techniques (Marques et al., 2015). Research suggests only trained athletes have the necessary skeletal muscle profile to respond to PAP…

Other protocols that have been used have involved plyometric exercises to potentiate the relevant muscle group prior to testing (Tobin et al., 2014). A plyometric exercise is defined as “a quick and powerful concentric movement, preceded by an active pre-stretch, or countermovement, that involves the use of the stretch-shortening cycle (SSC), and is used to exploit the elastic-reactive qualities of strength” (NSCA, 2016). The eccentric phase of the SSC has an increased amount of force on the muscle and therefore has an increased motor unit activation and firing frequency. This evidence highlights that plyometrics applies an amount of force needed in order to have a PAP response in a testing exercise (Taube et al., 2012). When using a complex lifting protocol or a plyometric protocol to induce a PAP response there is an element of fatigue that the body will have due to the increased loading put upon it (Neyroud et al., 2014). This fatigue has to be managed correctly by coaches and athletes to ensure the safe practice is adhered to protect the athlete and as well, reduce injury risk, therefore, minimizing the amount of fatigue by selecting appropriate PAP exercises is crucial (UKSCA, 2016). The immediate fatigue effect has been extensively studied to establish the optimum time for significant improvement in a performance test (Seitz et al., 2016) however, currently there is no evidence to show the effect off the potentiation and testing exercise on the athlete 24 hours’ post. This evidence would provide information on which protocol provides the optimum results but which is also the least demanding. This would enable the coach to conduct the most beneficial and efficient method of training in order to improve performance.

1.2 Aims

As previously mentioned evidence is lacking to determine the fatigue effect when comparing a complex lifting protocol against a plyometric protocol prior to PAP testing 24 hours post completion. The aim of the present research is to establish the protocol that will have the least amount of fatigue on a physically fit and trained athlete 24 hours post-testing.

1.3 Hypotheses

It is hypothesised that fatigue will be reduced in the athletes that complete a plyometric protocol as a PAP exercise when compared to a complex lifting protocol alongside significant testing results.

1.4 Delimitations

The subjects were male, physically fit and had a training background of more than two years and able to establish 1RM one week before completing the study. Subject completed a standardised warm-up followed by a complex lifting or plyometrics protocol to achieve PAP. All subjects carried out the vertical jump as a standardized strategies/methods of measuring performance. A protocol re-test was carried out 24 hours later as a measurement of fatigue.

1.5 Definition of Terms these need to be definitions as opposed to a glossary

NSCA – National Strength and Conditioning Association

PAP – Post-activation potentiation

PF – Peak force

RFD – Rate of force development

SSC – Stretch-shortening cycle

UKSCA – United Kingdom Strength and Conditioning Association

CHAPTER TWO LITERATURE REVIEW

This chapter will review the current literature that has studied post-activation potentiation and how complex lifting and plyometric protocols have been used to achieve it. Post-activation potentiation has been studied extensively and there is evidence stating that to achieve a PAP response a loading stimulus must be applied with an optimum rest period prior to testing. The immediate fatigue effect has been studied however there is evidence lacking between the relationship of PAP and fatigue 24 hours post-testing when comparing complex lifting protocols with heavy loading and plyometrics. This study provides information that can be used to enhance training programmes for athletes and coaches.

2.1 Post-activation potentiation

PAP can occur due to the contractile state of the muscles being affected by the increased rate of force development (RFD). This is the ability of the muscles to produce force in an efficient way (Bergmann et al., 2013). Achieving peak force (PF) and increasing the rate of force development in a training and competition environment is critical to maximising performance and is a factor that coaches should take seriously in athlete programming (Mullane et al., 2015). In order to achieve peak force, a maximal contraction needs to occur so a loading stimulus must be applied which can be in the form of a complex lifting protocol. A weight need is heavy enough so that the athlete has ability to increase the rate of energy development and change the velocity of the object being lifted (Haff et al., 2015) The impact of increased force assists the athlete in achieving a PAP response, this leads to increased activity of motor neurons and the recruitment of fast twitch muscle fibres (Lowery et al., 2012). When this happens the increased CA2+ released inside the sarcoplasmic reticulum enables the actin and myosin filaments to bind and establish cross-bridges so that a muscle contraction begins. It is said that when calcium concentration in the muscle is low that the sensitivity is increased and this is observed after a maximal or near maximal contraction (Wilson et al., 2013). Current research suggests that this effect is best seen in individuals with a higher total of type 2 muscle fibres and an extensive training background (Lim et al., 2013). Type 1 fibres have a greater capacity to carry out aerobic exercise and are innovated with smaller motor neurons compared to the larger type 2 fibres. Type 2 muscles fibres with their increased anaerobic capacity and amount of motor neurons need a greater stimulus in order to contract in comparison to the smaller type 2 fibres (Xenofondos et al., 2015). Mollica et al., (2012) took biopsies of muscle fibres from healthy recreational fit males and females between 19-27 years old. With a separation period of two weeks, biopsies were taken at rest and after 40 minutes of cycling at 60% of peak oxygen consumption. Results found that a chemical process called S-glutathionylation is responsible for the increase in force generation. S-glutathionylation of a cysteine residue on the troponin 1 molecule found in fast twitch muscle fibres is involved in sensing and responding to changes in calcium levels giving the muscle the ability to contract efficiently with less fatigue. Sasaki et al., (2012) found that fast twitch fibres responded better to nerve innovation after a brief stimulation when compared to slow twitch muscle fibres which are consistent with the hierarchical order of fibre activation. In a study by Seitz et al., (2016) which was carried out with 13 trained men, (mean ± SD: age, 24.1 ± 3.0 y; height, 1.85 ± 0.11 m; body mass, 86.1 ± 10.1 kg) using an isokinetic knee extension to measure the potentiating effect of a standardised warm-up protocol and conditioning activity. The study discovered that, men with a higher percentage of type 2 muscles fibres had the ability to generate a greater maximal knee extensor torque alongside having a larger cross-sectional area (CSA) and volume of quadriceps. This gives evidence that stronger individuals with greater CSA and volume of muscle with type two muscle fibres respond better to post-activation potentiation. This coincides with the theory of the hierarchical order of fibre activation that the larger type 2 muscle fibres with be activated before the type 1 fibres due to the increased loading stimulus applied to the muscle that is needed to achieve a Post-activation potentiation response.

2.2 Factors influencing Post Activation Potentiation

Research has proven that skilled athletes taking part in excessive stage game activities respond more in terms of performance to Post-activation potentiation than people who took part in recreational resistance training (Boullosa et al., 2016). The reason for this superior model shown in more aggressive athletes has been linked to their quicker recruitment of motor units as well as better rate of firing in assessment compared to untrained athletes (Suchomel, et al., 2016). Moreover, the capability of the motor neuron pool to withstand higher frequencies of activation, there may exist some other model occurrences: trained participates have extra synchronized motor unit recruitment hence in a shorter term an extra quantity of muscle fibres is contracting (Sygulla and Fountaine, 2014). Cuenca-Fernández, López-Contreras, Arellano, (2015) stated that participants with more maximal motor indicated more improvement in vertical bounce after a conditioning stimulus (4%) compared to participants with less maximal performance of 0.4%. Wilson et al., (2013) stipulated that greater skilled and stronger athletes experience less neural inhibition while lifting loads which are heavy and made a conclusion that the mixture of excessive as well as occasional intensities would be better-applied for individuals with an especially sound power education base compared to beginners. Chiu et al. (2003) advised that the one's subject’s education at better intensity would expand fatigue resistance as a model in their extensive schooling regimens, and had higher ability to recognize PAP. Though, showing improvement which are similar in participants with various force degrees after determining the impact on of energy in complex training to growth outcomes, it has been speculated that the amount of training for an athlete has minimal and insignificant impact on PAP (Sygulla and Fountaine, 2014). Another factor that influence Post-activation potentiation is the fibre of the muscles as well as their networks inside a muscle which is decided typically using genomic elements. It can also be inspired by means of activity stage and age. The improved outcomes shown with Post-activation potentiation is clearly seen in high depth sports that require excessive energy as well as pace. The overall outcomes in such sports relies upon on the level of speedy muscle fibres (type II). Research with small mammals (Sonne et al., 2015; Turner et al., 2012; Xenofondos et al., 2015; Wyland, Van and Reyes, 2015; Naclerio et al., 2015) showed that trainees with extra percent of type II muscle tissues fibers elicited a more response of PAP. In human beings, muscle tissues with a better percentage of type II fibres and individual with muscle groups of better percentage in kind II fibres, show off greater PAP (Mettler and Griffin, 2012) This is because rapid fibres experience greater phosphorylation of myosin regulatory mild chains in reaction to a conditioning pastime (Tomaras and MacIntosh, 2011) Currently, There are only few studies which examined the PAP variations among women and men Wyland, Van and Reyes, 2015; Hancock, Sparks and Kullman, 2015) A research by Gołaś et al., (2016) indicated that although women produced lowermost reaction pressure at some stage in jumping and did no longer leap as excessive as men, however no significant influence of gender between cycles was observed. Prior studies tested that, complex training influence both genders for basketball gamers (Seitz and Haff, 2016). However, unlike different research that discovered a huge improvement in the masculine gender and the same was not observed in the cases for feminine, non-statistically full-size fashion closer to development in complicated training performance changed into extra stated in female subjects and not in male subjects (Mettler and Griffin, 2012). Particularly, prior to and after complex exercise, women were found to jump about 0.5m and 0.6m respectively while men jumped about 0.8m 0.89m, respectively. The effects observed in J McGowan et al., (2015) propose that complex training has similar outcomes for oth males and females’ athletes, and consequently PAP impacts athletes and sportspersons without the subject of gender.

Naclerio et al., (2015) discovered that twitch potentiation turned into not observed at some point of ΜVC trial. Determining the impact of conditioning VCs of various intensities and intervals on twitch potentiation in plantar flexor muscular tissues it becomes concluded that VCs of less than seventy-five % MVC created little or no potentiation and that MVCs lasting five to ten seconds precipitated the best twitch potentiation (Puiu, 2014). Keeping in thoughts the effects of Puiu, (2014) observed something surprising: The potentiation of the twitch become determined after ballistic contractions which had been carried out at intensities as low as 20% of MVC. Nevertheless, Hancock, Sparks and Kullman (2015) studied the twitch potentiation after voluntary versus electrically induced isometric contractions in human knee extensor muscle groups, bolstered the outcomes of Puiu, (2014), because they determined that a voluntary isometric contraction of knee extensor at 25% MVC changed into not sufficient conditioning stimulus to set off twitch potentiation. It is documented that Post Activation Potentiation can enhance subsequent outcomes, and sports inclusive of heavy loaded squats have time and again tested their effectiveness in enhancing performance. vertical jump outcome Improvements had been found after successful completion of heavy lower back squats. It is also clear that a sizeable quantity of healing need to be offered after finishing the conditioning workout and the performance workout. Adequate rest time is not availed, minimal or not performance enhancement can be acquired. Individuals with better strength-energy ratios have additionally been speculated to be extra touchy to the PAP outcomes compared to their weaker opposite numbers. Getting a better understanding of the athletes group is vital in case you are to maximize the PAP results. Besides, the sort, volume as well as intensity of the conditioning training also affects the importance of the potentiation since most of these elements may affect fatigue quantity. This makes supplying correct education suggestions very hard, and also complicates the selection of the strength and conditioning teach while planning for the education programme. This is often the ultimate outcome of fatigue, which nonetheless lingers from the previous conditioning exercising. in case of too much relaxation, the potentiation might also expand, also resulting to no development in overall outcome. The PAP results are frequently considered as a ‘window of possibility’, or other times the Principle of Goldilocks. Nevertheless, with little rest, fatigue also lingers, so no visible improvement in performance. Too long rest, the potentiation dissipates, and once more no visible development performance. With enough rest the overall performance improvement is visible. This principle is known as ‘fitness-fatigue version’ and is validated in (Gołaś et al., 2016). It is in the interim that the fatigue dissipates that the PAP outcomes can be used. It has been established that most appropriate relaxation times differ among trainees and sports people. Trained athletes were proven to be greater to the impacts of PAP compared to untrained athletes. People with higher power tiers have additionally been found to also have a higher PAP sensitivity compared to weaker athletes. In García-Pinillos, Soto-Hermoso and Latorre-Román (2015) it is evident that fatigue emerges both peripherally or centrally to the principal worried device relying upon the kind of conditioning exercising. Regardless of this, the impacts are not completely understood. Additionally, studies into this topic is needed so that training experts can develop extra effective programmes of training which uses the PAP consequences.

Whilst conditioning physical games have been proven to potentiate the neuromuscular device, it has also been proven to set off a stage of fatigue – formerly defined through the fitness-fatigue model. These outcomes were extensively mentioned in big quantities of studies. In García-Pinillos, Molina-Molina and Latorre-Román (2016) a preliminary lower in overall performance was observed straight away after the conditioning exercising however then witnessed full-size increase after 4.5-12.5 mins of recuperation. The authors mentioned that this initial lower in overall performance become associated with fatigue. Again, the health-fatigue principle then shows that after the 12.5-minute rest, the overall performance ‘normalises’ as the potentiation subsides back to wherein it turned into earlier than the conditioning contraction. This means that, the length of the time of rest is crucial to the PAP impacts to be able to prevent any effects of the potentiation being masked by using fatigue. Thus, an ideal balance between the potentiation and relaxation time should be set up. However, many studies have researched o the various rest times to determine which period is simplest. Currently the matter is still debated and no formal agreement amongst researchers. Worst enough, no study critiques on PAP had been able to determine the best relaxation time, though Boullosa et al., (2018) stated a time period between 8-12 minutes. This consistent problem to isolate the most suitable relaxation time is absolutely because of the variability of individuals.

2.3 Post Activation Potentiation and Performance

Several research have tested the PAP influence on a repeated ballistic movement hobby like sprinting. Lovell, Bousson and McLellan (2013) stated that elite sprinters use protocols where they achieved 90% in their one repetition most (1RM) for 5 units of one cycle of the returned squat exercising with 2 mins rest between sets and 20 minutes prior to opposition, improved their performance I sprinting. Nibali, et al., (2015 ) indicated that 5 min, three maximal 90% of one RM attempt 5 sec maximal cycling pace accelerated, however, this potentiation turned into faded after 20m. on the other had Lovell, Bousson and McLellan (2013) used a heavy-load squat (HS) techniques including of one set of 3 cycles at 90% of the difficulty’s 1 repetition most (1RM) and at 4 minutes publish–warm-up, topics completed a timed forty-m dash with time measured at 10, 30m. The results indicated that, when preceded with a hard and fast of HS, participant ran 0.87% quicker within the 40-m dash in contrast to Control organization. The records from this have a look at endorse that an acute bout of low-extent heavy lifting with the lower frame might also enhance 40-m sprint instances. Lockie et al., (2015) discovered that after ten maximal 90% of 1 RM trials both jogging maximal velocity and acceleration changed into extended. This shows that there is likelihood of a wide variety of trials that influences PAP’s effect on ballistic overall performance. In a recent study which they consisted of a four-minute standardized heat-up, accompanied by means of 4-minute energetic rest, 100-m song dash, a 2d 4-minute energetic relaxation, a heat-up of 4RM parallel back half of-squat, a 0.3minute lively relaxation, finalized with a second one hundred-m song sprint; Linder et al. (2010), indicated that there was a sizeable development of 0.19 secs when the second one dash become preceded by a 4RM again-squat protocol. Concerning the software of PAP in exercise planning related to the going for walks overall performance, the following research has been determined. A blended software (Evetovich, Conley and McCawley, 2015) lasting nine weeks inclusive of eight-three RM and six maximal thirty trials executed after resistance influenced both leaping as well as walking overall performance. In another research by Tsimahidis et al (2010) a complicated resistance and strolling, speed application became designed. In this observe which became lasted 10 weeks a maximal 30m trial changed into finished among 5 resistance units eighty-85% of 1 RM. The acquired outcomes confirmed that acceleration, maximal speed and all types of leaping (squat, countermovement and drop jump) have been multiplied. Strength and velocity performance commonly calls for that, in a brief maximal effort, all relevant motor units are involved and fired at the possible maximum costs. PAP could seem to have little importance once motor gadgets are discharging at a very excessive costs since it cannot create excessive frequency pressure. However, there are additional effect; it is able to boom isometric fee of force improvement, even at surprisingly excessive stimulation frequencies at which isometric pressure is not elevated by the PAP way. Moreover, in rapid shortening contractions, the PAP impact is present at high frequencies. Whether PAP is effective at the motor unit firing prices achieved in rapid “ballistic” performance is at gift not recognised. Nevertheless, through increasing the fee of pressure development, it is able to beautify performance in sports which includes jumping, kicking, and throwing. Endurance performance commonly includes the submaximal contractions which reoccurs for extended durations. From the start of the overall performance, the contractions themselves would prompt the process answerable for the Post-activation potentiation. In the submaximal contractions, motor units sometimes tent to discharging at distinctly low quotes; as a result, the energy output of the motor units must be quantitated by the Post-activation potentiation. If a constant force must be maintained, the firing rates of the motor unit will need to decrease to catch up on the force which is improved. A decrease in motor unit firing price ought to, by using lowering the wide variety of muscle movement potentials and nerve impulses in line with unit time, postpone the onset of fatigue. For instance, the chance of neuromuscular transmission failure, muscle motion capacity propagation failure, and excitation-contraction coupling impairment is improved in share with the frequency of nerve/muscle movement potentials that need to be sustained. By reducing the required frequency, PAP ought to delay fatigue. In constant exercising, there's additionally the probability of impaired “significant force” to motoneurones. By growing the output of the force for any motor unit firing price, PAP may want to relieve the weight of retaining a high level of excitation of the motoneurones.

2.4 Complex Lifting Protocols

To achieve a post-activation potentiation effect in the muscle, a loading stimulus needs to be applied. This can be in the form of a complex lifting protocol otherwise known as a conditioning activity. These complex lifting protocols are completed by loading the muscle with a weight approximately between 70-95% 1RM alongside a ballistic activity in order to stimulate a PAP effect (Liossis et al., 2013). These loading protocols can come in various forms. Talpey et al., (2014) studied the effects of dynamic Vs static complex and contrast protocols and the effect of PAP on CMJ.Those that carried out the dynamic complex group showed significantly higher results (p < 0.05) when compared to the conventional protocol over the static complex and dynamic and static contrast. This provides evidence that a dynamic complex lifting protocol is more efficient in achieving a PAP result as a complex lifting protocol. As previously mentioned, athletes with a larger cross-sectional area and volume of muscle respond better to PAP. This increase in muscle volume coincides with an increase in strength and the ability to generate force (Seitz et al., 2013). The relative strength of an individual should be considered when programming a complex lifting protocol into a training schedule (Wang et al., 2016). Stronger, conditioned athletes express the ability to cope with the onset of fatigue which supports that weaker individuals do not respond the complex lifting protocols and that in order to elicit a PAP response from a complex lifting protocol an athlete should be able to back squat 2 x bodyweight (Suchomel et al., 2015). Selection of the exercises for a complex lifting protocol is key to achieving PAP. Complex lifting exercises can be different such as back squat Vs deadlift and can have varying effects on PAP (Swinton et al., 2011). Arias et al., (2016) studied the effects of using 85% 1RM deadlift as a PAP exercise by measuring peak ground reaction force (pGRF) during a single CMJ and found that pGRF decreased 15 seconds after stimulus but had no significant increase between 2-16 minutes. Fatigue was selected as the main contributor to the failure of this study and reasons such as the selection of appropriately conditioned participants may have been a factor or that deadlift is too demanding as a potentiation exercise which caused the potentiating effect to be offset by fatigue. Nibali et al., (2015) conducted an experiment to determine the optimal loading and rest period to achieve PAP by using a complex lifting protocol. Previous research concludes that the 5RM back squat can exhibit a PAP response so this was used for this study. They established participants 1RM and carried out a warm-up protocol of 10 reps at 50% 1RM, 5 reps at 70% 1RM and 3 reps at 90% 1RM with 2 minutes between sets to establish 5RM. A 5RM back squat set was performed followed 5 minutes later by 3 maximal bodyweight jump squats. Four minutes rest showed the optimum rest period to achieve PAP alongside loading of 5RM back squat with a heavy lifting warm up protocol reaching 90% 1RM.

2.5 Plyometric protocols

The majority of research studying PAP has used heavy loading protocols loading study participants with between 70-100% 1RM (Wilson et al., 2013). Isometric and dynamic lifting protocols have provided a stimulus with varying contractions and conditions such as time, frequency and load (Lim et al., 2013). More recent publications have used warm-up protocols and plyometric exercises to stimulate an increase in sensitivity to Ca2+ in the actin and myosin filaments and increase motor neuron recruitment (Smith et al., 2014). These protocols provide users to complete PAP without the need for heavy equipment to provide a stimulus in places such as competition venues with limited resources (Okuno et al., 2013). Turner et al., (2015) studied the effects of plyometrics as a way of achieving PAP on trained sprinters with plyometric experience of more than 2 years. Three sets of ten single leg bounds were completed after a standardised warm-up unweighted and wearing a weighted vest with 10% bodyweight. 10 and 20 metre sprint times were measured at 15 seconds, 2, 4, 8, 12 and 16 minutes to measure the effect of the plyometrics. The unweighted group showed an increase in sprint performance compared to the control group and the weighted group more than the unweighted. This shows that the use of single leg bounds as a plyometric exercise wearing a weighted vest will provide a PAP response and improve sprint performance over 10 and 20 metres. The failure of the study to achieve a PAP response with an unweighted vest provides evidence that loaded protocols stimulate the type 2 muscle fibres more efficiently. The use of vertical and horizontal exercises in plyometrics has recently been examined and it is thought that exercises that replicate the use of the muscle fibres in the same way as the competition exercise can improve performance. For example, a horizontal exercise would improve sprinting and a vertical exercise would improve jumping (Ramirez-Campillo et al., 2015). Singh et al., (2013) studied the effects of horizontal Vs vertical and combined horizontal-vertical groups against a control group using a horizontal depth jump and vertical depth jump. A 45-metre dash test was used to measure the results after a 10-week programme of 6 x 10 repetitions twice weekly. Significant results were found in all 3 groups compared to the control group however, there was no significance found between the groups although a combination of horizontal and vertical plyometric training provides better sprint performance. The selection of the type of plyometric exercise is crucial to achieving a PAP effect and improving performance via the use of maximal strength, explosive strength (speed-strength, strength-speed) and reactive strength (Wirth et al., 2015). Reactive strength exercises are affected by the stretch-shortening cycle and tendon stiffness with the stretch-shortening cycle being separated by slow or fast. Slow being defined as longer ground contact times (> 0.25 seconds) and fast as shorter ground contact times (< 0.25 seconds) (Beattie et al., 2014). A reactive speed test is a useful tool in determining the adaptation of reactive strength to measure the effectiveness of slow or fast reactive strength exercises in order to prioritise the goal or either speed-strength or strength-speed (Singh et al., 2015).

2.6 Fatigue

Understanding fatigue and its effects is an important factor in maximising performance to achieving PAP in order to establish the optimum amount of rest time that should be given before testing the effects (Naclerio et al., 2014). Literature has tested the effects of PAP at varying intervals between 15 seconds and up 20 minutes (Wilson et al., 2013) and measured the potentiating effect. Research has previously measured the effects of changing rest intervals between sets and reps as well as varying the intensity of the exercise to establish the ideal loading stimulus and intensity of which the load should be used (Boullosa et al., 2013). One study in particular by Gouvea et al., (2013) used squats and leg press as a conditioning activity on 12 healthy resistance-trained men and found that resting for 8-12 minutes before carrying out a vertical jump test was the optimal rest time so that a PAP effect occurs. They found that the group that rested between 4-8 minutes potentially suffered from fatigue so that no significant results were displayed. A factor could have been the conditioning status of the individual and their ability to offset fatigue in the early rest period. After loading with between 80-90% 1RM of rep ranges between 1 and 4 for up to 3 sets the phosphocreatine system may be depleted. In order for this to recover a time period of 3-5 minutes rest is needed for the energy system to recover (Bertuzzi et al., 2016). This factor and increase in fatigue may have been a cause to the shorter rest period (up to 8 minutes) not showing significant results. So that a measurement of fatigue can occur, the use of the fatigue index in anaerobic performance is used to determine the effect that an exercise may have on the ability to express power by measuring peak and low data and fatigue rate to measure the decline in power (Naharudin et al., 2013). The use of a force plate whilst carrying out a CMJ is a way of determining the decline in power after a PAP exercise (Sole et al., 2014). Gathercole et al., (2013) studied variables on the CMJ and fatigue test to measure the immediate effects and the neuromuscular effects 24 and 72 hours after the initial testing. A force plate was used to measure the effects of the fatigue test on the CMJ and found that at 0 and 24 hours jump duration increased and peak power decreased compared to baseline testing and that at 72 hours peak power returned to normal but with a slight increase in jump duration. This suggests that the fatigue test induces fatigue in resistance trained men but that fatigue will decrease between 24 and 72 hours after initial testing. Elements of the cause of fatigue may have been metabolic disturbances, a stretch reflex reduction in muscle stiffness and impaired excitation-contraction coupling (Twist et al., 2013). Esformes et al., (2010) carried out a plyometric protocol using 24-foot contacts with 5 minutes rest before testing and results showed an increase of fatigue which led to a decrease in performance. A study by Margaritopoulis et al., (2015) used 15-foot contacts with a 10-minute rest interval which demonstrated significant results in jump performance measured by height, power, force, and rate of force development. This increased rest and decreased loading stimulus enabled the participants to experience less fatigue whilst still experiencing the potentiating effect of the stimulus. Increased repeated loading, in particular, the eccentric phase of the muscle action may cause a decline in the stretch reflex contribution which would inhibit muscle spindle activity. This decreased stiffness is caused by the damage to the fibres such as the sarcomeres. With a loss of stiffness in the muscle, the lengthening of the muscle over repeated bouts of eccentric action increases and the level of fatigue would increase (Wadden et al., 2012).

2.7 Summary

This chapter has reviewed and it is widely accepted that post-activation potentiation is acknowledged as a way of increasing the performance of a physical test after a stimulus has been applied. There is a large amount of research confirming this (Wilson et al., 2013) (Chen et al., 2013) however, many studies have variables included in them that may affect the outcome. Such variables being the type of stimulus applied such as a complex lifting, plyometric protocol and breaking those down further into dynamic Vs static protocols that all have a potentiating effect. Other variables can include the intensity of the exercise, the frequency of how they are applied and the rest period that is optimal so that maximal performance is produced. The selection of appropriately trained participants is crucial to the success of PAP studies as the stronger individuals with an increased amount of type 2 muscle fibres with large cross-sectional areas and volume of the muscle being more susceptible to PAP (Seitz et al., 2016). These participants, as research suggests will be able to cope with increased load needed to display PAP as well as being able to offset the fatigue caused whilst utilizing the PAP effect on the muscle to maximise performance (Lowery et al., 2012) (Neyroud et al., 2014). This ability should be seen across complex lifting protocols and plyometric protocols as long as a history of both is demonstrated by the participants. The lack of training history and ability will only add another variable which will ultimately contribute to the potential failure of a study. Establishing the amount of fatigue caused by a complex lifting protocol and plyometric protocol as a way to induce post-activation potentiation is key information to any coach or athlete who wants to use PAP. This will enable to use PAP without causing an increased and unnecessary amount of fatigue on an athlete that will potentially put them at risk of injury and poor performance. Knowing what the effect of these protocols 24 hours after testing will provide important information and crucial evidence to which protocol is more beneficial as a PAP exercise.

CHAPTER THREE METHODOLOGY

The aim of this study was to establish which post activation protocol between a complex lifting and plyometric protocol was two-fold. Firstly, to establish which protocol has the greatest potentiating effect and secondly to establish which of those protocols had the least fatiguing effect measured by a repeat procedure 24 hours later.

3.1 Participants

The study selected 12 participants with resistance and plyometric training history of at least 2 years. All subjects were male (n=12; age 32.5 ± 1.87 years). They read and signed Par Q and consent forms (Appendix 1) after a brief of the study. Prior training experience in resistance training and plyometrics was crucial due to the aim of expressing PAP without unnecessary fatigue that would hinder performance. All participants were free from injury at the time of testing and 3 months prior. Ethics approval was given by the University of St Mark and St John for all testing and procedures. Anthropometric data is as follows;

3.2 Protocol

All participants received a full brief of the study they were to complete and anthropometric data were collected. Each participant was randomly assigned to either the complex lifting group or the plyometric group. A standardized warm-up was carried out before either protocol or testing were completed. 24 hours later the standardised warm-up was carried out again and the same protocol replicated to establish the effect of fatigue.

3.3 Procedures

All participants received a full briefing on the details of the study and then signed a Par Q and consent form which was stored in a secure location. Participants blindly selected a protocol at random and then anthropometric data was collected. Height and body fat was measured using a Multi-Frequency Body Composition Analyzer, model MC-180MA made by Tanita in Tokyo, Japan, (software, Health Monitor V2.7.8). Height was measured in cm using the Seca mechanical telescopic measuring rod. A standardised warm-up was then carried out which consisted of a 5-minute cycle on a wattbike pro with model b Bluetooth monitor at 90 rpm with no brake engaged and resistance set at 3. 5 bodyweight squats were carried out followed by 5 alternate jump lunges on each leg. 3 vertical were performed at 50%, 75% and 90% or maximal effort. A two-minute rest was given before either of the protocols was followed. The Complex lifting protocol completed a back squat using an eleko 20kg Olympic bar and eleiko Olympic lifting plates in a Hammerstrength half squat rack completing 3 x 3 of 85% 1RM with 3 minutes between sets. After each squat 5 box jumps were completed using a Jordan Plyometric Soft Box. The plyometric group carried out 3 x 5 weighted drop jumps with 3 minutes rest between sets. After each protocol, a standardised rest period was given before attempting the vertical jump at 4, 8 and 12 minutes after the potentiating exercise. The participants stood next to the wall with their shoulder 15 cm away keeping both feet flat on the floor and then reached up and made a mark on the walk with the chalk on their fingers. The vertical jump was then performed beginning with a counter movement down to a knee angle of 90 degrees. The hands were able to swing back and then up to reach the wall. Participants jumped as high as possible marking the highest point by touching the wall with the chalked fingers. This was repeated three times with the highest score being recorded. A period of 24 hours was given before the same protocol was carried out again in exactly the same conditions.

3.4 Testing and Measurements

Testing was completed in three parts. Part one was 1RM testing of back squat carried out one week before the study commenced. Part two was to carry out either the complex lifting or plyometric protocols and part three was the re-testing protocol carried out 24 hours later to measure fatigue. All testing and measurements were carried and collected by a Physical Training Instructor.

3.5 Participants Strength

Participants attended a session one week prior to the study to establish their 1RM. The purpose of this was to test the strength capacity of the participants and measure their back squat 1RM and to ensure that they can squat at least 1.7 x bodyweight to ensure that they were strong enough to achieve a PAP response when using the complex lifting protocol. This enabled the study to exclude any participants that were not suitable due to an insufficient strength capacity.

3.6 Data Analysis

A dependent T-Test was undertaken to compare complex lifting Vs plyometric group as well as to compare the results 24 hours post-testing to measure fatigue. Statistical analysis was carried out using Microsoft Excel Spreadsheet with Analysis ToolPak. A mean ± st dev has been taken of all data and represented on the graphs. Accepted significance is represented as p0.05. All data is based upon a population sample of n=12.

CHAPTER FOUR RESULTS AND FINDINGS/DATA ANALYSIS

4.1 My Results

The results were obtained in two groups, 6 participants performed the complex lifting while the rest 6 undertook the plyometric protocol before a vertical jump. The results were as follows;

The vertical jump data from the pre-test period of the experiment and the other three times at times 4 minutes, 8 and 12 are recorded in two tables, Table 1 and 2 and the data is presented graphically in Figure 1 and 2. First, 6 participants engaging in the plyometric protocol show that there is a significant difference between a lack of plyometric post-active potentiation and after. Prior to potentiation, the study identified that the participants’ vertical jump was 39±0.4281cm. After a plyometric protocol, the results show that potentiation is achieved as respective mean VJ (vertical jump) 3*3 (4, 8, 12 minutes) measures are 41.15 ±0.5602, 42.28 ±0.50, 44.21 ± 0.4969 respectively. A significant increment in potentiation was clearly observed as is clearly shown by the significant increase in the mean length of vertical jump with the increase in the time of plyometric protocol. The second part of the experiment involving complex lifting protocol shows a significant difference between performance in vertical jumps pre-test (prior to the performance of the protocol) and after the protocol; 38.26 ±0.5432 and 40.3 ±0.3596, 41.63 ± 0.4142, 42.4 ±0.4464 respectively. Similarly, it was observed that performance improved with the number of times that the participants performed the protocol which indicated better performance with post-activation potentiation. Thirdly, on the questions on which of the two protocols show the highest post-activation potentiation, the study observed that performance was better after a plyometric protocol compared to a complex lifting protocol: plyometric protocol; 41.15 ±0.56, 42.28 ± 0.5, 44.21 ±0.49 and complex lifting protocol; 40.3 ±0.35, 41.68 ±0.41, 42.4 ±0.44. Lastly, the study compared the effects of PLY and RES in maximizing the vertical jump performance. The most striking result to emerge from the data was that, immediately after both exercises, performances reduced; however, once the participants repeat the exercise, performances were remarkably improved. Based on this observation, it is clear that potentiation and fatigue coexist in that when fatigue is high, the performance (in this case vertical jump), and declines. However, potentiation is enhanced and therefore the participants' performance is improved. An increase in the participant's muscle performance after a protocol is dependent on the net balance between muscle potentiation and fatigue. This means that with potentiation dominance, muscle performance increases if fatigue declines. If fatigue and potentiation are in equal levels, or fatigue dominates, then performance will remain unchanged or will decline. Considering the participants at individual levels to evaluate how each experienced potentiation is vital. As already determined, participants received potentiation after performing each of the protocols. However, this evaluation does not show how the participants responded in minutes 4, 8 and 12. For the plyometric protocol, participant 1 showed the highest performance with a mean of 42.4 ±0.85. Participant 3, on the other hand, showed the rest performance and therefore the least potentiation with a mean of 41.15 ±1.15. As already determined, less potentiation indicates domination of fatigue and therefore less performance. Participants 4, 5, 6 showed a relatively high performance with means of 41.4 ±1.23, 41.87±1.04, 41.57 ±0.61. For the second protocol, complex training, participant 4 and 5 showed the highest performance with means of 41.1 ±1.44 and 41 ±0.61. The 1st participant performed the least for this group and for both groups in this study. While fatigue was a crucial factor for this study, the observation made for individual performance showed that there are a number of factors that affect the potentiation. In particular, for this study, the participant’s experiences with high power performance and a potentiation protocol.

CHAPTER FIVE DISCUSSION

Studies clearly show PAP has the advantage of an athlete’s high power past training for invoking PAP in strength-primarily based movements (Seitz et al., 2014; Sygulla and Fountaine, 2014). stronger men in a lower back squat as per Seitz et al., (2014) and ballistic and nonballistic concentric-handiest 1/2-squats (Suchomel et al., 2016) skilled greater will increase in squat leap outcomes following the utilization of these as potentiating sporting events. Basically, the use of plyometrics training to invoke a reaction of PAP, a trainee better positioned to revel in these outcomes. Within this argument, participants tend to undergo extra upgrades at greater time points after the JS30. This shows high force may have an impact at the dash potentiation experienced next plyometric sporting events. Future PAP studies of plyometrics, as well as vertical and countermovement jump should try and affirm this observation and show the impact on that extra energy. This is especially actual based on importance and the PAP response timing. the pattern size within the research precluded using statistical evaluation to evaluate the complex training and JS30, there are a few vital factors that may be mentioned from the percentage potentiation outcomes. The upgrades to vertical jump overall outcomes were small; starting from 1-4% across all the subjects in the three situations. these results have similarity to those mentioned throughout other studies’s literature (Evetovich et al., 2015; Smith et al., 2014; Turner et al., 2015; Barbosa, Barroso and Andries, 2016). This offers a basis for the case evaluation. Additionally, it is vital for the researcher to consider each of the three participant’s skilled jump performance improvement following rest after the two training protocols. With regard to the three conditions, it was established when evaluating any critical distinction in potentiation, though it cannot be proved that JS30 can promote vertical jump performance or overall outcomes compared to other conditioning protocols such as the complex training protocol used in this research. Much like previous PAP research (Evetovich et al., 2015; Turner et al., 2015), it is obvious that there have been people responses to the conditioning sporting activities. The extent as well as timing of the potentiating’s consequences of the complex training and PLY had varieties among the participants. based on the results of the past studies, plyometric conditioning is more effective. However, there are similar investigations comparing the efficacy of plyometric conditioning to complex lifting. Moreover, whilst plyometric preconditioning changed based on its relation with an advanced performance, this leads us to conclude that PAP is probably the operating process. Additionally, different mental as well as physiological factors plays a position in the voluntary overall outcomes. This indicate that, future research needs to use responses of muscle twitch to evaluate potentiation and as well remark greater conclusively on causation. Another vital issue to consider is the utilization of blood lactate as a fatigue’s oblique marker. This study did not determine the ammonia ranges in blood as well as intramuscular ATP. Additionally, the concentrations of PCr was not determined since it needs invasive process including a muscle biopsy. Nevertheless, physical overall outcome checks (CMJ and vertical jump), even though significantly utilized for determination of football overall outcomes, do not virtually indicate the intermittent repetitive, and high-depth nature of performance. Low skill based protocols with jumps which are repeated can be investigated to simulate initial sport overall outcomes. The consequences established that the level of exercising used within the current research is efficient in initiating potentiation. In football for example, high-intensity walking is carried out almost every 70 seconds. The quantity of excessive-pace walking is what distinguishes pinnacle-magnificence gamers from those at a lower stage. Therefore, accelerated performance would make contributions to better performance inside an exercising; but, specific testing is required to look at higher overall performance in some specific sports. The acute results of plyometric and resistance complex training has not been seen in some stages of the competitive section of the gamers to keep away from the confusing consequences of precompetitive extended stress as well as anxiety following opposition but determining the real sport outcome following preconditioning can additionally create extra realistic clue on its application in sensible settings. 1-RM squat and 0-12minute dash outcomes, energy-workout induced PAP is proven to be efficient in appreciably growing CMJ peak. promotion of the loaded-CMJ peak of 2.8% in individuals four minutes after acting a single set of five maximal repetitions of squats has been identified. A vertical jump potentiation process precipitated an increase in CMJ height best at 12 minutes. The distinction is because of the layout of the test. As per Nibali et al., (2015), athlete’s performance units of five loaded CMJ (as pre-load), observed through the squat training potentiation protocol and ultimately through one set of five loaded-CMJ (put up-load). A complex training program period of four minutes between the sets changed into imposed and the consequences were in comparison among before as well as after load. This means that, induction of PAP to this protocol may have resulted from the completed exercise and not most effective from the squat exercise process. In truth, the ultimate time among the 1st pre-load checks as well as put the upload test in the Nibali et al., (2015) became 16 min.

As formerly discussed, not only is the time complex training program period a vital element for maximal PAP manifestation, however additionally other elements that are included in this method. These elements encompass the layout of the potentiation process, the kind of high power training as well as the revel in of the individuals. It is therefore hard to evaluate this examine to other studies as some of the elements range greatly. manifestation of PAP is discovered at one of kind time periods after the potentiation protocols’ utility in numerous research. These pre-load durations differs between different periods; 5 min and 20 min particularly, a majority of these elements want to be put to consideration whilst potentiation applications are utilized by trainees who intend to grow. Research has analyzed results the manifestation of PAP on sprint duration and strolling velocity. When in comparison to other research, the vertical jump potentiation protocol stepped forward sprint duration best at the post- 10 minutes and post-12 minutes’ durations. Various researchers concluded that no impact of various potentiation protocols on sprint performance while the people were evaluated after a quick duration of the utility (short time). Puiu (2014) found that a back-squat potentiation process (10 unmatched repetitions at 90% of 1RM) does not enhance vertical jump outcomes in the long term. The counter jump movement protocol (1 set of 3 cycles) didn’t show improvement in sprint duration post-four minutes. After the protocols of PAP, both fatigue as well as potentiation should coexist and in this case the balance between those elements are determinants within the very last overall outcome of next high energy training. Past research indicate that the duration of four minutes is needed for creatine phosphate repair and the PAP effectiveness can be discovered up to twenty minutes. In the current investigations, fatigue influence can have a negative consequence on PAP at 4min just after the potentiation protocol of the DJ. In another study, (Barbosa, Barroso and Andries, 2016) observed an improvement in 40-minute sprint duration (0.87%) in soccer players after four minutes of applying a single sets of three cycles of heavy-loaded squat at ninety percent of 1RM, however, no impact changed into determined when the athletes were subjected to a loaded- CMJ protocol (one set of 3 repetitions) within the very research indicating potentiation process design is a vital issue for manifestation of PAP. The results from compare to that of preceding research in which BLa was asessed after maximal or submaximal exercising. The outcomes are also constant with a preceding investigation by Smith, et al., (2014) who concluded that the bottom pH become visible one minute after the exercise, regardless of the workload, after which interstitial pH recovered in a nearly exponential way. Contrary to the hypothesis, this study did not discover a vast distinction between the protocols. However, this isn't always specifically sudden based on the fact that other than the ammonium, lactate, and uric acid accumulation, also contributes to fatigue improvement. (Cuenca-Fernández, López-Contreras, and Arellano, 2015). Accumulation of uric acid, lactate, and ammonium which are higher can be detected after a workout process, ad usually results in a low energy group of the muscle; the feasible reason for this may be that there is decreased or modified mechanism of feedback from the muscle tissues which are fatigued after the training. Moreover, there can be high pastime of AMP deaminase, which hinders muscular free ADP concentration increase hence limiting muscle contraction abilities, which, in flip, pushes the muscle to better tiers of fatigue and, ultimately, better energy disturbance. On the other hand, ATP or PCr decreased amounts or each inside the fast twitch or high-glycolytic fibers will also be a full-size contributor to fatigue. the size of blood uric acid as well as ammonia tiers and intramuscular PCr/ ATP concentrations changed into past the scope of this research. the relationships determined in physical performance as well as BLa permit us to state that after the BLa were high, fatigue dominated and the physical outcomes was reduced, but because the lactate began to subside, potentiation took over and brought about an increase in bodily overall performance above the baseline.

CHAPTER SIX CONCLUSIONS AND RECOMMENDATIONS

The findings drawn in this study indicate that the vertical jump height of sportspersons is potentiated by complex lifting and plyometric protocol in over 0-4 minutes, 0-8 minutes and 0-12minutes. Further, this study sort to compare these two protocols to determine which one has the most potentiation to an athlete or a sports person when they are exercising. Several conclusions can be drawn from the findings in this study. First, the study clearly showed that the two PAP protocols are significantly effective in increasing the performance in power exercises. Notably, however, various factors influence the effectiveness of PAP programs when they are sued to enhance performance for sportspersons. Some of these factors comprised of the time needed for maximal induction, the design of the protocol, the type of exercise and the training experience of the trainee. This study focused at the two potentiation protocols (complex lifting protocol involving completing a back squat using an eleko 20kg Olympic bar and eleiko Olympic lifting plates in a Hammer strength half squat rack completing 3 x 3 of 85% 1RM with 3 minutes between sets. After each squat 5 box jumps were completed using a Jordan Plyometric Soft Box. The plyometric group carried out 3 x 5 weighted drop jumps with 3 minutes rest between sets. After each protocol a standardised rest period was given before attempting the vertical jump at 4, 8 and 12 minutes after the potentiating exercise). It was established that these two are acute power training methods that could be effective to be used to improve athletes and other sportspersons to improve their power and performance for vertical jumps in competition or during training. Importantly, while the two are effective, it was established that using the time tested, performance is affected by the protocol used. Particularly, results showed that performance was improved more after a plyometric as the potentiation protocol than when complex lifting was used. Lastly, fatigue and the impact it has on performance was determined in which the study concluded that fatigue and potentiation affect performance in an inverse relationship. When fatigue is high, as was the case for complex lifting exercise (a heavy resistance exercise), performance declines. On the contrary, when the potentiation is high (as was evident in plyometric exercise), performance is positively affected. In this study, after a 24 hours rest, participants who had been engaged with PLY showed better performance as compared to those tested using the RES protocol. Having made these conclusions, this study recommends further studies on these study topics. This recommendation should be focused on determining whether the two potentiation protocols could be used together to improve performance for a high power exercise.

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