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Athletes expect improved high-intensity performance following warm-up, and postactivation potentiation (PAP) is assumed to contribute to this improvement. However, the scientific evidence supporting this assumption is incomplete. PAP is known to result from prior muscle activation, and should enhance maximal effort contractions of very short duration. However, PAP dissipates over 4-6 min after the PAP-inducing contraction, so PAP should not contribute to enhanced performance more than 5 min after the warm-up.
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CURRENT OPINION / OPINION COURANTE
Should postactivation potentiation be the goal of
your warm-up?
Brian R. MacIntosh, Marie-Eve Robillard, and Elias K. Tomaras
Abstract: Athletes expect improved high-intensity performance following warm-up, and postactivation potentiation (PAP) is
assumed to contribute to this improvement. However, the scientific evidence supporting this assumption is incomplete. PAP
is known to result from prior muscle activation, and should enhance maximal effort contractions of very short duration.
However, PAP dissipates over 46 min after the PAP-inducing contraction, so PAP should not contribute to enhanced per-
formance more than 5 min after the warm-up.
Key words: complex training, myosin light chains, posttetanic potentiation, fatigue.
Résumé : Les athlètes sattendent à lamélioration de leur performance de forte intensité à la suite dun échauffement; la po-
tentialisation postactivation (PAP) expliquerait en partie cette amélioration. Toutefois, les données probantes appuyant cette
hypothèse sont insuffisantes. La PAP dépend, on le sait, dune activation préalable du muscle et devrait améliorer la perfor-
mance maximale au cours de contractions de très courte durée. La PAP se dissipe dans les 4 à 6 min suivant la contraction
linitiant; en conséquence, la PAP ne contribue pas à lamélioration de la performance plus de 5 min après léchauffement.
Motsclés : entraînement complexe, chaînes légères de myosine, potentialisation post-tétanique, fatigue.
[Traduit par la Rédaction]
Introduction
Warm-up is a customary practice, with a long history, car-
ried on by most athletes prior to competition. Warm-up is
done with the expectation that it will enhance the subsequent
performance relative to that which could be expected if the
warm-up was not done. In this current opinion, we will de-
scribe important design features of high-quality research con-
cerned with warm-up and this will be followed by a
discussion of postactivation potentiation (PAP) in the context
of these design features. Stretching may be considered an im-
portant part of the warm-up (Behm et al. 2011), but will not
be discussed here.
For a considerable time now, it has been recognized that a
consequence of prior muscle activation is an enhanced con-
tractile response called PAP that originates within the
muscles. It is our belief that essential information is missing,
and we cannot yet confirm that PAP can actually contribute
to the improved performance that relates to warm-up.
Research design considerations
There are several key features of appropriate research de-
sign that we propose to be ideal to evaluate the mechanism
of warm-up and (or) the impact of a given warm-up on sub-
sequent performance. Key features of ideal design (see
Fig. 1) include the following: (i) comparison between at least
2 conditions in an appropriate population; (ii) familiarization
of subjects with measurement tasks; (iii) random order of the
warm-up conditions between trials on separate days; (iv) blind
or preferably double-blind approach.
It seems appropriate to use athletes in a warm-up study be-
cause they are the ones who are going to compete. Typically,
subjects should be asked to perform some kind of criterion
event, similar to their competition, with and without a prior
warm-up (2 conditions), and the performance is evaluated
statistically to see if the performance is better after one of
these conditions. Each condition or type of warm-up should
be performed on a different day to remove the potential ben-
efit of having already performed the criterion task on that
day.
The major confounding effect of research concerned with
warm-up is the learning effect. Without the opportunity to
practice the criterion event, the apparent improvement could
be attributed to learning how to do the event. The learning
effect can be diminished by randomizing the order of testing.
The control condition may be no warm-up at all, or may be a
standard warm-up that is being compared with a modified
(experimental) procedure. Note that randomization without
familiarization sessions will increase variability and diminish
the likelihood of finding statistical significance.
Received 19 December 2011. Accepted 18 January 2012. Published at www.nrcresearchpress.com/apnm on xx April 2012.
B.R. MacIntosh, M.-E. Robillard, and E.K. Tomaras. Faculty of Kinesiology, University of Calgary, Calgary, AB T2N 1N4, Canada.
Corresponding author: Brian R. MacIntosh (e-mail: brian@kin.ucalgary.ca).
546
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Ideally, warm-up research should be done in a double-
blind manner. In a double-blind study, the subject is unaware
of the treatmentthey are receiving, and the person doing
the measurements is not aware of the treatment. It is impossi-
ble to be sure whether the subject is unaware of the warm-up
they have done, but they should not be aware of the antici-
pated outcome. Similarly, the person doing the outcome
measures could be excluded from the room while the subject
participates in the treatment (e.g., control or experimental
warm-up), so if they do have bias with respect to the poten-
tial impact of doing the warm-up, this cannot affect the re-
sult.
In warm-up research, every attempt must be made to con-
trol as many confounding factors as possible. If we want to
investigate whether or not PAP can contribute to improved
performance, it is important to control for muscle tempera-
ture, which can improve performance (Asmussen and Bøje
1945; Binkhorst et al. 1977). One way to do this would be
to compare a PAP-inducing warm-up with a passive warm-
up that warms the muscles to a similar temperature. The fol-
lowing should also be controlled: time of day, relative hydra-
tion, diet, training the day before, and potential ergogenic
aids like caffeine. The more consistent the conditions of per-
formance are from one day to the next, the more likely the
investigators are to find a small significant difference.
Now we would like to turn our attention to PAP, and crit-
ically evaluate the research concerned with PAP in the con-
text of warm-up.
Postactivation potentiation
PAP is a contractile response for a given stimulation that is
enhanced due to prior voluntary activation. The prior volun-
tary activation is referred to as a conditioning contraction. In
the past, PAP has most often been confirmed by measuring
the increase in amplitude of a twitch contraction after a con-
ditioning contraction (Baudry and Duchateau 2007; Tomaras
and MacIntosh 2011). A twitch is the contractile response to
a single activating stimulus (electrical pulse) delivered to the
motor nerve or directly to the muscle. This should be done
with supramaximal stimulation so all available motor units
are activated. Immediately after a maximal effort voluntary
contraction, the twitch can be enhanced by more than 100%.
This enhancement dissipates over the next few minutes (see
below). However, following a conditioning contraction, teta-
nic contractions are potentiated to a less extent than twitches
(MacIntosh and Willis 2000), and maximal voluntary isomet-
ric force is not affected by PAP.
It is important to recognize that PAP is analogous to stair-
case and posttetanic potentiation (PTP) (MacIntosh 2010).
The term activity dependent potentiationcan be used to re-
fer to all of these.
The mechanism of activity dependent potentiation relies on
myosin light chain kinase (MLCK), which is activated by an
increase in intracellular free [Ca2+] (Grange et al. 1993). Ca2+
is released from the terminal cisternae of skeletal muscle, and
in parallel with initiating contraction, this Ca2+ activates
MLCK. Phosphorylation of the regulatory light chains of my-
osin promotes mobility of the myosin heads (Levine et al.
1996), and this increases the rate at which cross-bridges form
when the muscle is activated (MacIntosh 2010; Sweeney and
Stull 1990). The increased rate of cross-bridge formation al-
lows a faster rate of force development.
Phosphorylation of proteins is one way the body provides
short-term memory. Only the motor units that were activated
will have this memory, and fast-twitch motor units have a
higher activity of MLCK so they respond with a greater level
of regulatory light chain phosphorylation (Grange et al.
1993). The memory dissipates as dephosphorylation of the
regulatory light chains occurs, by activity of light chain phos-
phatase. Typically, any phosphorylation achieved by a given
contraction is lost after 56 min of inactivity. This means
that any enhancement of performance attributable to PAP
can only be effective within a short time-frame (15 min)
after the conditioning contraction(s).
The downside of prior activation
There are actually 2 consequences of prior activation of
muscle: fatigue that tends to diminish the contractile response
Fig. 1. A schematic showing the components of an ideal study on the impact of warm-up. Optional parts are shown with grey shading. At
least 2 familiarization experiences must be allowed before the evaluation of performance begins. This is shown here as test 1 and test 2. These
familiarization sessions can be used to obtain additional measurements, such as twitch amplitude prior to and after the warm-up of interest.
Statistical comparison of performance will be done for test 3 and test 4. Additional sessions would be required if more than 2 warm-up pro-
cedures were being compared. The recoveryportion is essentially the time between the end of the warm-up and the time the task of interest
is performed.
MacIntosh et al. 547
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and potentiation, which tends to enhance the contractile re-
sponse (Rassier and MacIntosh 2000). It is convenient to
think of these 2 processes as having distinctly different mech-
anisms (MacIntosh 2003); fatigue is a consequence of down-
regulation or attenuation of excitationcontraction coupling
(MacIntosh and Shahi 2011) and potentiation is a conse-
quence of myosin regulatory light chain phosphorylation
(Grange et al. 1993). The impact of any voluntary contraction
on subsequent contractile response depends on the balance
between these 2 opposing effects. A key point to be aware
of is that potentiation is most evident for twitch contractions
and at low frequencies of activation (MacIntosh and Willis
2000); this means that when both potentiation and fatigue
are present, fatigue will dominate as frequency of activation
increases (Grange and Houston 1991; Rassier and MacIntosh
2000).
How could PAP enhance all-out effort
performance?
Considering that maximal effort contraction will be of rel-
atively high frequency, and potentiation is less evident under
this condition, it becomes difficult to accept that PAP could
enhance this performance. Let us look more closely at the
theoretical considerations that led to this proposal.
The known change in kinetics of cross-bridge formation
that results from regulatory light chain phosphorylation, dur-
ing and after a voluntary contraction, causes a greater rate of
force development during subsequent maximal effort volun-
tary contractions (Baudry and Duchateau 2007). This change
in rate of force development is the basis for the theoretical
enhancement of performance of all-out effort activities. The
consequences of an increase in rate of force development are
illustrated in Fig. 2. Here it can be seen that if the contraction
is very brief, a greater force can be achieved when the rate of
force development is enhanced, even when maximal force is
not altered.
Baudry and Duchateau (2007) have shown that a 6-s iso-
metric contraction of the thumb elicits PAP, and will result
in a greater rate of force development during subsequent
maximal effort voluntary contractions and during brief high
frequency stimulation. These observations confirm that PAP
can enhance brief maximal effort contractions. However,
these contractions were isometric, and athletic performance
is typically dynamic. Ultimately, we want to know whether
or not PAP can contribute to improved dynamic performance.
Does PAP enhance all-out performance?
There have been several recent studies (Tables 1 and 2)
that purport to evaluate whether or not PAP can enhance
short duration, high-intensity performance. Table 1 summa-
rizes the studies that have used electrical stimulation to quan-
tify the presence of PAP or fatigue. Table 2 summarizes
studies that have not attempted to confirm the presence of
PAP. Furthermore, several of the studies in Table 2 have
evaluated performance at a time when PAP would have dissi-
pated; 5 min or longer after the voluntary contraction that
would have been expected to cause PAP. A few specific stud-
ies will be critically evaluated here.
Gossen and Sale (2000) tested their subjects for maximal
effort dynamic contractions at a variety of loads, then had
their subjects perform a maximal voluntary contraction
(MVC), which lasted 10 s, to elicit PAP. One minute after
the 10-s contraction the subjects repeated the maximal dy-
namic contractions for measurement of power. Gossen and
Sale also tested their subjects without the intervening 10-s
contraction (control condition), and these 2 trials were done
in random order. Gossen and Sale reported no significant en-
hancement of power as a consequence of doing the 10-s
MVC. They concluded that fatigue probably dominated the
response at the time they made these measurements, and
they suggested that a longer wait after the conditioning con-
traction might be more appropriate.
French and colleagues (2003) had subjects perform 3 × 3 s
and 3 × 5 s maximal isometric contractions. They compared
performance with a control condition (no maximal isometric
contractions), and evaluated performance for each of the fol-
lowing: power output during 5 s of cycling, countermove-
ment jump, drop jump, or maximal effort isokinetic knee
extension. The general approach was test, conditioning con-
tractions, retest. The post-test evaluation took place immedi-
ately afterthe third maximal voluntary contraction, though
in the case of cycling, 20 s of easy exercise preceded the 5-s
maximal effort test. The longer duration (5 s) conditioning
contractions had no positive influence on performance. Fol-
lowing the short (3 s) contractions, knee extension and drop
jump performance were improved. There was no significant
improvement in cycling or countermovement jumps. The sub-
jects in this study did not have a familiarization session prior
to the day on which they were evaluated, but the sequence
was randomized; an approach that should minimize the learn-
ing effect. Considerable variability is evident from their
fig. 3, which shows almost as much difference between pre-
test means for 3 × 3 s and 3 × 5 s trials as between the pre-
test and post-test for 3 × 3 s for drop-jump acceleration
Fig. 2. A pair of maximal contractions are superimposed. One has a
faster rate of force development, similar to what would be expected
with postactivation potentiation. It is clear that if the contraction was
terminated early, the force of the potentiated contraction would be
greater than that of the control contraction. This is not the case if the
duration of the contraction is long enough to allow similar force de-
velopment.
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impulse; one of the measures that had a significant differ-
ence.
The major problem with this study is that we have no way
of knowing if PAP allowed the improved performance of the
vertical jump, or if some other factor, like practise during the
initial trial or increased temperature, was responsible for al-
lowing the improvement. Furthermore, it is unclear how they
performed the statistics for this study, because they appa-
rently did not always have a pretest measurement. It is also
not obvious how many visits to the lab were allowed. If sub-
jects did all of the criterion tests on one day, then the delay
between the conditioning contraction and the test would vary.
Chiu et al. (2003) utilized a rest period of 5, 10, or
18.5 min following a heavy resistance exercise warm-up and
assumed PAP was present between 5 to 18.5 min. It is impor-
tant to note that Chiu et al. (2003) measured a squat perform-
ance but not the presence of PAP. Others have used similarly
long intervals between the warm-up and the performance;
PAP would not be expected to contribute to these improved
performances.
Temperature is given as a possible contributing factor for
the performance enhancement recently reported by Mitchell
and Sale (2011). They evaluated twitch amplitude 4 min after
the conditioning contractions (5-repetition maximum squat),
and confirmed the presence of PAP at that time. Performance
of countermovement jumps was enhanced by this condition-
ing contraction, but not in the control condition when the
5-repetition maximum squat was not done. Their methods
confirm the presence of PAP at the time performance was
enhanced, but do not rule out other factors contributing to
the improved performance.
Conclusions
Despite the recent interest in examining the role of PAP in
dynamic contractions, we still have little conclusive evidence
that PAP can enhance athletic performance. Many studies
purport to have evaluated the role of PAP in warm-up in an
attempt to show that prior high intensity muscle activation
can result in improved performance, but without confirming
that PAP was present (see Table 2). Of interest, many of
these studies do show enhanced performance when a brief
high-intensity component is included in the warm-up. This is
an important outcome of this research, even if the mechanism
is not known.
Table 1. Warm-up studies concerned with postactivation potentiation with twitch confirmation.
Study What was the VCM? Performance improved? FamiliarizeaRandom Control
Baudry and Duchateau 2007 Thumb adduction Yes Yes Yes No
Gossen and Sale 2000 Dynamic knee extensions No Yes Yes Yesb
Miyamoto et al. 2011 Plantar flexion Yes Yes Yes Yesb
Mitchell and Sale 2011 CM Jump Yes Yes Yes Yesb
Tomaras and MacIntosh 2011 30-s Wingate test Yes Yes Yes Yesc
Note: CM, countermovement; VCM, Voluntary criterion measurement.
aYes if allowed familiarization on separate day.
bNo warm-up.
cStandard warm-up protocol.
Table 2. Warm-up studies that refer to postactivation potentiation without twitch confirmation.
Study What was the VCM?
Performance
improved? FamiliarizeaRandom Control
Chiu et al. 2003 Rebound jump squats No Yes No Yesb
Concentric-only jump squats No
Chiu et al. 2004 Isometric knee extension No No No No
French et al. 2003 Drop jump Yes No Yes Yesb
CM jump No
5-s cycle sprint No
Knee extension Yes
Kilduff et al. 2007 CM jump Sometimes Yes No No
Ballistic bench throw Sometimes
Koch et al. 2003 Standing broad jump No Yes Yes Yesc
Saez Saez de Villarreal
et al. 2007
CM jump height Yes No Yes Yesc
CM jump height with load Yes
Drop jump height Yes
Scott and Docherty
2004
CM vertical jump No No Yes No
CM horizontal jump No
Young et al. 1998 Vertical-loaded CM jump Yes No No No
Note: CM, countermovement; VCM, Voluntary criterion measurement.
aYes if allowed familiarization on separate day.
bStandard warm-up protocol.
cNo warm-up.
MacIntosh et al. 549
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Acknowledgements
This research was supported by NSERC.
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... Postactivation potentiation (PAP) is a phenomenon traditionally characterized as an increased contractile response for a known activation observed after a voluntary conditioning contraction (i.e. conditioning activity [CA]) (MacIntosh, 2010;MacIntosh, Robillard, & Tomaras, 2012). The primary mechanism responsible for PAP relies on myosin light chain kinase (MLCK), which is activated by increased intracellular free [Ca 2+ ], and results in phosphorylation of the regulatory light chains of myosin (Grange, Vandenboom, & Houston, 1993). ...
... (2) to verify the influence of a plyometric CA on voluntary RTD during a maximal isometric contraction of knee extensors. This study used a cross-over design, with a control and experimental condition, in which the same participants performed both experiments (PAP and PAPE measurements) in a randomized order, following the recommendation of previous reviews (Blazevich & Babault, 2019;MacIntosh et al., 2012). ...
... Before the evaluations, the athletes remained sitting quietly for at least 10 min to remove any warm-up or residual PAP that walking to the laboratory might have caused. This allows true interpretation of the real effect of only the CA (MacIntosh et al., 2012). Then, participants were positioned on the isokinetic dynamometer (Biodex Medical Systems 4, Shirley, NY, USA) with the lateral epicondyle of the knee aligned with its axis. ...
Article
Purpose The objective of this study was to evaluate a plyometric conditioning activity (3 sets of 5 countermovement jumps, [CA]) for twitch properties and voluntary knee extension. Methods After a familiarization session, fourteen highly-trained sprint athletes, 12 men (23.25 ± 7.17 years) and 2 women (23.0 ± 2.8 years) performed 2 experiments, each in a randomized order (crossover design). In one experiment, the time-course of twitch contractile properties was evaluated with and without the previous CA at 2, min intervals to 10 min of recovery. In the second session, maximal voluntary knee extension was evaluated at the same recovery intervals, for control and experimental condition in random order. Results Mixed-model ANOVA with Bonferroni post-hoc revealed significant differences between pretest and 2 min (p<0.01, ES=0.42) and 4 min (p<0.01, ES=0.20) for peak twitch torque of quadriceps femoris muscles confirming postactivation potentiation [PAP] at these times. Twitch rate of torque development (RTD) was significantly greater than pretest value only at 2 min (p < 0.01, ES=0.58) after the CA. Twitch contraction time and ½ relaxation time were not significantly difference from pretest values after the CA (p>0.05). No significant difference was observed for voluntary RTD following CA. Conclusion The plyometric CA increased twitch peak torque and RTD consistent with PAP; however, there was no effect of CA on voluntary RTD of knee extension at any time after the plyometric CA. Even with PAP confirmed, we observed that the CA fails to improve isometric RTD of quadriceps femoris muscles.
... Nevertheless in the 1970's, Burke et al. (1976), wanted to distinct it from post-tetanic potentiation or staircase potentiation so they used this term; they referred to repetitive activation Page | 86 REVUE DE LITTERATURE at frequencies and with numbers of pulses compatible with natural activation. Now, it is commonly accepted by many authors that PAP is induced by voluntary activation of the muscle (at maximal or near-maximal intensities) whereas post-tetanic potentiation is induced by an involuntary (electrical) tetanic stimulation (Sale, 2002 ;Macintosh et al., 2012). ...
... This study demonstrated that PAP can be in effect for up to 12 minutes following the conditioning exercises, with the 4 minutes minimum recovery time following the conditioning exercises seemingly sufficient to allow the fatiguing effects to subside. According to Macintosh et al. (2012), the light chain myosin is phosphorylated from 1 to 5min, which is considered the optimal time for a potentiation and according to the authors, it creates a contraction "memory" to enhance performance. After 5min, this contraction "memory" dissipates and the potentiation effect is weaken. ...
... In a practical side, it is true that the muscular performance can be improved after a CC, but it is not known whether the increase in muscular performance commonly observed after a PAPinducing CC is a consequence of acute neuromuscular alterations relating to the CC itself or whether it simply reflects warm-up and/or familiarization effects (Macintosh et al., 2012). ...
Thesis
Swimming is a very demanding sport which requires extreme muscle strength and endurance. Only fractions of a second may separate the winner from the opponents. The swimming performance, specifically, is influenced by complex interactions between physiological, morphological, neuromuscular, biomechanical, and technical factors. These factors not only depend on training, genetics, and opportunity but also can be influenced by a “warm-up,” recognized as a primary factor in athletic performance. Completion of a warm-up prior to a competitive exercise bout is a widely accepted practice within modern sport; athletes and coaches believe that warm-up is very essential to attain optimal performance. Consequently, this thesis proposes an easy method for coaches to implement during the competition warm-up or before the race in call room to improve the performance of their athletes. This technique is called post-activation potentiation (PAP). However, the effects of PAP and swimming performance remains limited. Consequently, our three studies contributed to the knowledge of this subject. Our results provided practical information for coaches to develop appropriate training paradigms for their swimmers. The revealed data reported the importance of PAP individualization to enhance swimming performance and described some basics that should guide the warm-up structure in the competition. Many factors can affect the PAP impact on performance such as the transition time between the PAP stimulus and the subsequent main activity (swimming race), the typological profile and muscle strength of swimmers (the percentage of fast, slow fibers...), the level of training experience and the load or intensity of the PAP stimulus. Nevertheless, PAP effect in swimming still lack the information to understand how it works and specially to allow better application in practice. However, it is necessary for each trainer or physical trainer to proceed by trial and error to determine, for each athlete, what is the optimal recovery time in order to enhance the performance. According to the literature, the potentiation effect can be measured between 1min to 12 minutes before the race. This duration should be short enough to maintain potentiation but long enough not to induce an accumulation of fatigue. The optimal average time is often around 6 to 8 minutes, which corresponds to the time the swimmer waits in the call room. However, many protocols are to be tested, science must continue to study this phenomenon to know its most effective use in swimming performance
... Several studies had suggested that PAP in the warm-up resulted in improving performance during explosive performance, such as jumping [16,17]. The effect of PAP would dissipate over 4-6 min after the PAP-inducing contraction [18]. However, it has been shown that the PAP effects could occur at 3, 6, 9, and 12 min after a conditioning activity [19]. ...
... The other explanation is neurological: it has been observed an increased motor neurons excitability during the contraction produced by PAP. However, since the effect of PAP would dissipate over 4-6 min after induced [18], the results of the current study cannot be explained by this neurological factor. ...
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The purpose of this study was to investigate the benefit of post-activation performance enhancement (PAPE) after accentuated eccentric loading (AEL) compared to traditional resistance loading (TR). Sixteen male volleyball athletes were divided in AEL and TR group. AEL group performed 3 sets of 4 repetitions (eccentric: 105% of concentric 1RM, concentric: 80% of concentric 1RM) of half squat, and TR group performed 3 sets of 5 repetitions (eccentric & concentric: 85% of 1RM). Countermovement jump (CMJ), spike jump (SPJ), isometric mid-thigh pull (IMTP), and muscle soreness test were administered before (Pre) exercise, and 10 min (10-min), 24 h (24-h), and 48 h (48-h) after exercise. A two-way repeated measures analysis of variance was used to analyze the data. Peak force and rate of development (RFD) of IMTP in AEL group were significantly greater (p < 0.05) than TR group. The height, peak velocity, and RFD of CMJ, height of SPJ, and muscle soreness showed no interaction effects (p > 0.05) groups x time. AEL seemed capable to maintain force production in IMTP, but not in CMJ and SPJ. It is recommended the use of accentuated eccentric loading protocols to overcome the fatigue.
... Previous studies have reported such potentiation enhancement effects on impulsive strength capacities after the completion of high intensity, low volume resistance training workouts [2][3][4]. Initially, the PAP effect was associated with an enhanced muscle contractile response for a given level of stimulation following an intense voluntary contraction, which is measured as the maximum twitch force evoked by supramaximal electrical stimulation [5]. This effect can be explained by an increased recruitment of higher-order motor units along with the rate of phosphorylation of myosin regulatory light chains [5,6], which can elicit potentiation for a subsequent short period of time (<5 min) [7]. ...
... Initially, the PAP effect was associated with an enhanced muscle contractile response for a given level of stimulation following an intense voluntary contraction, which is measured as the maximum twitch force evoked by supramaximal electrical stimulation [5]. This effect can be explained by an increased recruitment of higher-order motor units along with the rate of phosphorylation of myosin regulatory light chains [5,6], which can elicit potentiation for a subsequent short period of time (<5 min) [7]. Nonetheless, the time course of the previously described classic PAP effect is shorter than the reported window of potentiation observed in several studies (>3 to 16 min) [8]. ...
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This study examined the short-term effects (post 6 h and 24 h) of two equated (70% of 1 repetition maximum (1-RM)) low volume resistance exercise protocols: (i) velocity-controlled (VC) and (ii) repetition to failure (RTF) on upper and lower body performance in competitive adolescent male basketball players. Following a randomized, counterbalanced design, ten participants (age: 16 ± 0.5 years) completed either VC or RTF separated by 72 h. VC consisted of 4 sets of 5 explosive repetitions (≥90% of the maximum velocity). RTF involved 2 sets of 10-RM (with no velocity control). Measurements of 20-m sprint, countermovement jump (CMJ) and medicine ball toss (MBT) were collected before (baseline), post 6 h and 24 h after either VC or RTF. Increases of CMJ post 6 h (VC, +6.7%; RTF, +2.4%) and MBT post 24 h (VC, +4.6%; RTF, +4.2%) were observed after both VC and RTF. Only VC potentiated CMJ after 24 h (+2.0 ± 2.3%). No other changes or differences between protocols were observed. Performing a low volume exercise protocol, either VC or RTF, induced similar potentiation effects on the vertical jump (post 6 h) and medicine ball toss (post 24 h) in adolescent basketball players. Only the VC protocol was still effective to potentiate CMJ performance after 24 h.
... It is also plausible that the conditioning activity is too soft and does not significantly influence the contractile capacity of the muscles nor physical performance [3,4]. Therefore, the objective is to apply an adequate protocol of muscle pre-activation that results in subsequent improvements in muscle contractile responses (i.e., greater force production) and physical performance [5]. ...
... Much interest has been given to the idea that potentiation could be used during warm-up to improve sports performance [1,5]. However, there is no current consensus regarding the most effective potentiation protocol [3,6]. ...
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It is currently unknown the most effective potentiation protocol to increase maximum strength. Hence, we investigated the separated and combined effects of post-tetanic potentiation (PTP) induced by whole- body electrostimulation (WB-EMS) and post-activation potentiation (PAP) induced by voluntary maximum isometric contractions on maximum isometric strength. Ten trained males were randomly evaluated on four occasions. In session A, maximum isometric strength (split squat) was measured in minutes 1, 4, and 8. In session B, the measurements were taken in minutes 2, 6, and 10. In session C, a WB-EMS protocol was applied to elicit PTP and the measurements were performed in minutes 1, 4, and 8. In session D, the same WB-EMS protocol was applied and the measurements were taken in minutes 2, 6, and 10. No signi cant differences in maximum isometric strength were observed between: (i) the control and WB-EMS in minutes 1 vs. 1 and 2 vs. 2; (ii) the control and PAP in minutes 1 vs. 4, 1 vs. 8, 2 vs. 6, and 2 vs. 10; and (iii) the PAP and WB-EMS plus PAP in minutes 4 vs. 4, 8 vs. 8, 6 vs. 6, and 10 vs. 10. In contrast, the WB-EMS plus PAP revealed a signi cant increase of 54% (~450 N) compared to the WB-EMS in minutes 4 and 8 compared to the minute 1 (p < 0.001), but not between minutes 2 vs. 6 and 2 vs. 10. The present results showed that PTP induced by WB-EMS in isolation or combined with PAP induced by voluntary maximum isometric contractions did not produce a signi cant increase in maximum isometric strength compared to the control and PAP alone, respectively.
... Increased voluntary drive to the muscle after high-intensity muscle contractions has been proposed as a potential mechanism explaining voluntary performance enhancement after a warm-up (Güllich et al., 1996). In the present research, EMGVL,T180/M increased by 1.6 ± 28.1 and 3.5 ± 40.1% after task practice for CA300 and CA60, respectively (see Table 3.2), thus indicating a 'learning' effect after task practice (MacIntosh et al., 2012;Mina et al., 2019), that is, extensive task-specific practice induced self-organisation of the motor pattern, resulting in greater agonist EMG amplitude, and then ultimately provoking an enhancement of voluntary muscle performance. EMGVL,T180/M increased from post-TP to 1 min post-CA in CA300 (6.5 ± 38.0%; see Table 3.2), but decreased during the same time in CA60 (-7.8 ± 40.9%; see Table 3.2). ...
... No control condition was included in the present research, meaning we could not control for Tm, nutrition or hydration strategies or compounding measurement error associated with repeated measurements. However, it should be noted that this present research attempted to control for Tm by passively heating the muscle as recommended by (MacIntosh et al., 2012), however, this data was not included in the thesis due to the extreme localisation of the passive heating protocol, meaning comparisons could not be made with the active warm-up. Nevertheless, this is an important delimitation to consider for future research. ...
... As verification of PAP requires observation of increased peak twitch force/torque and increased rate of twitch force/torque development, which are verified via electrical stimulation of single muscles/muscle groups (3,24,35), it may, however, be suggested that Banister model (23) and postactivation performance enhancement (PAPE) (35) are the most appropriate explanations of the acute effects of weighted implements based on the recommended mechanisms of the included studies. However, although these models may sufficiently explain reports of enhanced batting performance following a weighted bat warm-up in studies using a stationary target, the findings of studies assessing such effects when intercepting a dynamic target potentially diminish the efficacy of attaining such potentiated peripheral states. ...
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Jermyn, S, Neill, CO, and Coughlan, EK. The acute effects from the use of weighted implements on skill enhancement in sport: A systematic review. J Strength Cond Res 35(10): 2922–2935, 2021—Weighted implements are used before competitive performance with the aim of enhancing motor skill execution on return to the standard implement. The purpose of this review was to analyze the existing literature pertaining to the acute effects of weighted implements on respective sporting performance. Following a systematic screening process, 25 studies were identified. This review highlighted the effects of (a) weighted balls and bats on throwing and batting performance and (b) indoor weight throw implements on indoor weight throw performance. Studies reported conflicting effects on immediate performance post–warm-up with the respective implements. Notably, although overweighted bats and overweight attachments are a prominent preparatory tool in baseball, this review found consistent and repeated evidence of degraded batting performance in striking-based studies. Decreased bat velocity, altered swing patterns, subjective-objective mismatches of bat speed and weight, temporal accuracy errors, and inadequate recalibration to the standard bat were identified as acute effects. This review identified an obvious dearth of research into the acute effects of weighted implements on motor skills in other sports with equally complex perceptual motor patterns, such as football (soccer), golf, rugby, basketball, and American football. Future weighted implement research should investigate the acute effects of respective implements on motor skill performance in other sports, such as those aforementioned, with the purpose of exploring relevant implications for preparatory strategies and immediate performance on return to the standard implement.
... Although some researchers argued that PAP effect is short-lived (1-5 min depending on myosin light chains phosphorylation) (Macintosh et al.,2012;Bevan et al.,2010), PAPE, on the another hand, as shown in numerous human studies takes at least several minutes to appear (6-10 min) and then may last for > 15 min is based on muscle temperature, muscle blood flow and/or water content, increased neural drive and increased muscle-tendon stiffness (Blazevich & Babault, 2019). For that reason, after each treatment, participants undertook an 8 min. ...
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Introduction: Alternating a resistance exercise with a plyometric exercise is referred to as "complex training". Purpose: This study aimed to compare the acute post-activation performance enhancement (PAPE) effects of the Barbell Back Squats (SQ), Drop Jumps (DJ) and Complex Training Method (CT) in terms of vertical jump height (VJ) and Reactive Strength Index (RSI) in physically active individuals. Methods: Nineteen participants (11 male and 8 female) who resistance train at least 3 times/week volunteered this study. Participants performed three experimental sessions namely; SQ, DJ and CT loading sessions with 48 hours interval with a randomized, crossover study design. SQ was performed roughly at 90 % of 1 Repetition maximum (1 RM) of the participants with three repetitions (3RM). In DJ session, participants performed 2 sets of 10 drop jumps with 3 min rest whereas in CT sessions, participants performed 5 drop jumps followed by 3RM back squats. Participants were tested for VJ and RSI before and 8 minutes after each treatment. Results: Within-group differences (pre vs. post-intervention) were only present for RSI performances for the CT group (p=0.004). No between-group differences (i.e. SQ, DJ and CT) were evident for VJ (p=0.93) and RSI (p=0.87) performances respectively. Conclusion: These findings demonstrated that none of the loading protocols with above mentioned exercises and methods have any detrimental or improving effects on VJ height and RSI for physically active individuals who joined this study. This study also showed that SQ, DJ exercises and CT method can be used interchangeably and safely to avoid training monotony during longer training periods for chronic adaptations.
... Some studies have suggested that PAP dissipates over ∼5 minutes after the conditioning activity, 11 whereas a recent metaanalysis indicated that a rest interval of 8 to 12 minutes may be able to provide the greatest PAP benefits. 12 Based on the latter, we chose the same recovery interval of 8 minutes, but found that it was not adequate to enhance 50-m swim performance. ...
... Some studies have suggested that PAP dissipates over ∼5 minutes after the conditioning activity, 11 whereas a recent metaanalysis indicated that a rest interval of 8 to 12 minutes may be able to provide the greatest PAP benefits. 12 Based on the latter, we chose the same recovery interval of 8 minutes, but found that it was not adequate to enhance 50-m swim performance. ...
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Middle-aged individuals may not respond in a similar manner as younger individuals. The study's objective was to examine the effect of static (SS) and dynamic stretching (DS) in young and middle-aged men on subsequent performance. Ten young (22 ± 1.4 years) and 8 middle-aged men (46.3 ± 6.5 years) participated in 3 conditions consisting of SS (4 × 30 s for right and left quadriceps, hamstrings, and plantar flexors), DS (8 × 30 s of bilateral butt kicks, walking lunges, and plantar flexors) and control. Dependent variables included sit and reach, hip extension flexibility, countermovement jump (CMJ) height, drop jump (DJ) height, static balance, reaction (RT) and movement time (MT). Measurements were taken pre-intervention, post- and 10 min post-intervention. A 3-way repeated measurement ANOVA revealed that the younger men had higher jump heights, faster RT and MT, and greater flexibility than the middle-aged men. DS significantly enhanced DJ (p = 0.04) and CMJ (p = 0.006) height compared with SS and control conditions. SS (p < 0.0001) and DS (p = 0.004) post-intervention sit and reach scores were significantly greater than pre-intervention scores. There were no significant differences between the SS and DS sit and reach scores. CMJ heights were impaired (p = 0.04) by SS. Conversely, DS post-intervention jump heights were significantly (p < 0.0001) higher than SS post-, control post-, and control 10 min post-intervention. SS-induced impairments and DS-induced enhancements of CMJ height were not affected by age. DS provided similar improvements in sit and reach scores as SS. DS is recommended as the most appropriate stretching routine prior to work or athletic performance for younger and middle-aged men.
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The aim of this study was to determine the effect of different types of active warm-up stimuli of muscle activation on explosive jumping performance after short (5 min postwarm-up) and long (6 h postwarm-up) recovery periods following warm-up. Twelve trained volleyball players (21-24 years) performed different types of specific warm-up stimuli (WP) after baseline measurements [e.g., countermovement jump (CMJ) without and with extra load and Drop jump (DJ)] on randomized separate occasions: (1) three sets of five jumps with extra load (WP1), (2) two sets of four reps at 80% of 1RM parallel squat (1RM(PS)) and two sets of two reps at 85% of 1RM(PS) (WP2), (3) two sets of four reps at 80% of 1RM(PS) and two sets of two reps at 90% of 1RM(PS) and two sets of one rep at 95% of 1RM(PS) (WP3), (4) three sets of five DJs (WP4), (5) specified warm-up for a volleyball match (WP5), (6) three sets of five reps at 30% 1RM(PS) (WP6), and (7) an experimental condition of no active warm-up. Height in DJ significantly improved (P < 0.05) after WP1 (4.18%), WP2 (2.98%), WP3 (5.47%), and WP5 (4.49%). Maximal power output during CMJ with extra load significantly improved (P < 0.05) after WP2 (11.39%), WP5 (10.90%), WP3 (9%), and WP1 (2.47%). High-intensity dynamic loading (e.g., 80-95% 1RM), as well as specific volleyball warm-up protocol bring about the greatest effects on subsequent neuromuscular explosive responses. Acute positive effects on jumping performance after warm-up were maintained after long recovery periods (e.g., 6 h following warm-up), particularly when prior high-intensity dynamic actions were performed.
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The traditional warm-up (WU) used by athletes to prepare for a sprint track cycling event involves a general WU followed by a series of brief sprints lasting ≥ 50 min in total. A WU of this duration and intensity could cause significant fatigue and impair subsequent performance. The purpose of this research was to compare a traditional WU with an experimental WU and examine the consequences of traditional and experimental WU on the 30-s Wingate test and electrically elicited twitch contractions. The traditional WU began with 20 min of cycling with a gradual intensity increase from 60% to 95% of maximal heart rate; then four sprints were performed at 8-min intervals. The experimental WU was shorter with less high-intensity exercise: intensity increased from 60% to 70% of maximal heart rate over 15 min; then just one sprint was performed. The Wingate test was conducted with a 1-min lead-in at 80% of optimal cadence followed by a Wingate test at optimal cadence. Peak active twitch torque was significantly lower after the traditional than experimental WU (86.5 ± 3.3% vs. 94.6 ± 2.4%, P < 0.05) when expressed as percentage of pre-WU amplitude. Wingate test performance was significantly better (P < 0.01) after experimental WU (peak power output = 1,390 ± 80 W, work = 29.1 ± 1.2 kJ) than traditional WU (peak power output = 1,303 ± 89 W, work = 27.7 ± 1.2 kJ). The traditional track cyclist's WU results in significant fatigue, which corresponds with impaired peak power output. A shorter and lower-intensity WU permits a better performance.
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With a single activation, a skeletal muscle fiber, motor unit or whole muscle will yield a twitch contraction. The twitch is not an "all-or-none" response, but a submaximal response that can vary from one time to another. Prior activation causes myosin regulatory light chain (RLC) phosphorylation, by an enzyme called myosin light chain kinase. This phosphorylation dissipates slowly over the next several minutes due to a slow activity of light chain phosphatase. Phosphorylation of the RLC increases the mobility of the S1 head of myosin, bringing the S1 head in closer proximity to the myosin binding sites on actin. This increased mobility increases the rate of engagement of cross-bridges and increases the rate of force development and contraction magnitude on subsequent twitch or other submaximal contractions. We call this increased contractile response "activity dependent potentiation". With sequential twitches or incompletely fused tetanic contractions, the term staircase is used to describe the progressive increase in amplitude of contraction. If a twitch is elicited after a tetanic contraction, we call the enhanced response posttetanic potentiation. Stretching a muscle fiber to a longer length will also bring the actin filaments close to the myosin heads. This increases the Ca²(+) sensitivity, independent of RLC phosphorylation. At long sarcomere lengths, the impact of RLC phosphorylation is diminished, because Ca²(+) sensitivity is already increased. Similarly, lowering the temperature at which the muscle is tested increases Ca²(+) sensitivity. At low temperatures, staircase and posttetanic potentiation are diminished, but RLC phosphorylation still occurs. Activity dependent potentiation is an important functional modulator of contractile response.
Article
The purpose of this research was to determine whether a loaded countermovement jump (LCMJ) could be enhanced if preceded by a set of half-squats with a 5-RM load. Ten subjects experienced with the squat exercise performed 2 sets of 5 LCMJ, 1 set of 5 squat reps with a 5-RM load, and 1 set of 5 LCMJ with 4 min rest between all sets. There was no significant difference between the first 2 sets of LCMJ, and the repeatability between these sets was high. However, the jump height for the set of LCMJ after the squat set was significantly greater (2.8%) than for the LCMJ set immediately preceding the squats. It was concluded that squats with a 5-RM load produce dramatic improvements in power performance. In addition, there was a significant correlation between performance enhancement from the squats and the 5-RM load. This suggests that stronger individuals may benefit more from resistance training exercises that utilize contrasting loads. (C) 1998 National Strength and Conditioning Association
Conference Paper
To determine if training status directly impacted the response to postactivation potentiation, athletes in sports requiring explosive strength (ATH; n = 7) were compared to recreationally trained (RT; n = 17) individuals. Over the course of 4 sessions, subjects performed rebound and concentric-only jump squats with 30%, 50%, and 70% 1 RM loads. Jump squats were performed 5 minutes and 18.5 minutes following control or heavy load warm-ups. Heavy load warm-up consisted of 5 sets of 1 repetition at 90% 1 RM back squat. Jump squat performance was assessed with a force platform and position transducer. Heavy load warm-up did not have an effect on the subjects as a single sample. However, when percent potentiation was compared between ATH and RT groups, force and power parameters were significantly greater for ATH (p < 0.05). Postactivation potentiation may be a viable method of acutely enhancing explosive strength performance in athletic but not recreationally trained individuals. (C) 2003 National Strength and Conditioning Association
Article
It is a well established fact that the body temperature increases during muscular exercise, and that the increase is regulated (NIELSEN, 1938). It was the purpose of this paper to study the effect of the increased body temperature on the performance of maximum work, viz. a work performance of short duration (12 to 15 seconds) and a work performance lasting 4 to 5 minutes. The effect on a peak effort (a “push” or a “pull”) was also studied.The experiments showed:1) A given amount of work could be performed better – i. e. in a shorter time – when the organism was warmed up by a preliminary work. Also a greater muscular tension could be developed when “warmed up” than when not.2) A passive warming up – e. g. by means of radio diathermy or by hot baths – also increased the capacity for work.3) Massage had no beneficial effect on the performance.4) The harder the preliminary work was, the higher rose the temperature and the better was the performance (only demonstrated in the work of shorter duration (12 to 15 sec.)).5) The increased ability to perform hard work is closely correlated to the temperature of the working muscles.6) The maximum oxygen uptake is slightly higher when the organism is warmed up than when this is not the case, but the oxygen necessary for a certain amount of work is reduced.From these results it is concluded that a higher temperature in the muscles benefits the ability to perform work by accelerating the chemical processes in the muscles, probably also by decreasing the intramuscular viscous resistance. The accurately regulated higher rectal temperature in work (NIELSEN) allows the muscles to obtain a higher temperature during work than would otherwise be possible.
Article
Active skeletal muscles are capable of keeping the global [adenosine triphosphate (ATP)] reasonably constant during exercise, whether it is mild exercise, activating a few motor units, or all-out exercise using a substantial mass of muscle. This could only be accomplished if there were regulatory processes in place not only to replenish ATP as quickly as possible, but also to modulate the rate of ATP use when that rate threatens to exceed the rate of ATP replenishment, a situation that could lead to metabolic catastrophe. This paper proposes that there is a regulatory process or "peripheral governor" that can modulate activation of muscle to avoid metabolic catastrophe. A peripheral governor, working at the cellular level, should be able to reduce the cellular rate of ATP hydrolysis associated with muscle contraction by attenuating activation. This would necessarily cause something we call peripheral fatigue (i.e., reduced contractile response to a given stimulation). There is no doubt that peripheral fatigue occurs. It has been demonstrated in isolated muscles, in muscles in situ with no central nervous system input, and in intact human subjects performing voluntary exercise with small muscle groups or doing whole-body exercise. The regulation of muscle activation is achieved in at least 3 ways (decreasing membrane excitability, inhibiting Ca2+ release through ryanodine receptors, and decreasing the availability of Ca2+ in the sarcoplasmic reticulum), making this a highly redundant control system. The peripheral governor attenuates cellular activation to reduce the metabolic demand, thereby preserving ATP and the integrity of the cell.
Article
Weight lifting exercise may induce postactivation potentiation (PAP), thereby enhancing performance of a subsequent biomechanically similar "explosive" movement. However, it has not been shown that weight lifting induces PAP, indicated as potentiation of muscle twitch force. Therefore, the present study tested whether a five repetition maximum squat (5-RM squat) both induced PAP and increased the height of subsequently performed counter-movement jumps (CMJs). Eleven male athletes completed four laboratory sessions on separate days. Two sessions determined whether the 5-RM squat induced PAP: in one, a quadriceps maximal twitch was evoked immediately before and 8 min after a set of five CMJs (control); in the other, a twitch was evoked before a CMJ set, which was followed by a 4-min rest, a 5-RM squat, a 4-min rest, and a second twitch. Another two sessions tested the effect of the 5-RM squat on jump performance: in one session, two sets of five CMJs were performed with an 8-min rest between the sets (control); in the second, a 5-RM squat was performed 4 min after the first set of CMJs, and then after another 4 min the second set of CMJs was performed. Neither twitch torque nor CMJ height changed in the control sessions (P > 0.05). In contrast, interpolation of the 5-RM squat increased (P < 0.05) both twitch torque (49.5 ± 7.8 to 54.8 ± 11.9 N m; i.e., PAP = 10.7%) and CMJ height (48.1 ± 5.6 to 49.5 ± 5.9 cm; 2.9%). Since PAP was present at the time when CMJ height increased, it was concluded that PAP may have contributed to the increased CMJ height after a 5-RM squat.
Article
The purpose of this study was to examine whether postactivation potentiation (PAP) influences dynamic torque development in humans. Nine recreationally active men performed sets of 3 maximal isokinetic concentric plantar flexions at 180 degrees/second in the following sequence: before and immediately (5 seconds) after a 10-second maximal voluntary contraction (MVC) and then every 1 minute until the 5-minute point, followed by 1 more stimulation at the 10-minute point. Twitch responses were recorded before every set of 3 concentric contractions to examine whether the PAP exists. The twitch and concentric torques were potentiated at 0 through 5 minutes and 1 through 3 minutes post-MVC, respectively (p < 0.05), whereas there was no significant difference in concentric torque in the control (without MVC) condition (p > 0.05). For electromyographic signals during concentric contractions, muscle activity of the medial gastrocnemius was significantly depressed only immediately after the conditioning MVC (p < 0.05). These results indicate that a brief maximal voluntary isometric contraction enhances voluntary dynamic performance through PAP, within proper recovery interval. From a practical point of view, in sports activities we suggest undertaking PAP through high-intensity contractions 1 to 3 minutes before voluntary ballistic or plyometric actions for improved performance.