Getting an Edge: Primer Sessions
A primer session refers to a short and intense training session performed on or before game day with the objective of potentiating the central nervous system (CNS) and thereby creating a positive state of readiness and potentially positively influencing match performance (Harrison et al., 2019). Additional benefits from training with high intensity close to a game can include a positive hormonal response and potentially improved mood of an athlete. Of course, any session prior to competition must not create unnecessary fatigue and there must be adequate time between a primer session and the warm-up of a match to ensure there are two separate events and stimuli, and not simply a prolonged match day warm up.
There is ample evidence that suggests the use of a primer session can have a positive impact on performance, however; there are some key considerations prior to implementing such a strategy. This article will outline some key considerations and guidance regarding the use of primer sessions for rugby players.
In athletic populations the use of heavily loaded movements followed by unloaded explosive movements has been demonstrated to be an effective training method in acutely improving performance measures. This Post-Activation Potentiation (PAP) method is well documented, and a use of both ballistic and heavy loaded movements can be implemented to potentiate the CNS and improve athletic markers (Kilduff et al., 2011). Researchers have studied the effects of using similar methods of training and the effects it can have on performance hours and even a day later. For example, in a study that investigated rugby players’ use of a morning primer session and its effects on afternoon performance, it was found that there was a positive effect on athletic markers six hours later (Cook et al., 2014). In this study, the researchers investigated the use of heavy resistance training, sprint training or no training in the morning and the differences those sessions had on peak power output and sprint performance later in the day. It was reported that the largest change in performance came from the morning session with a heavy resistance protocol where players worked up to 3-rep maximums on both squat and bench press.
Other research that has investigated different modes of exercise for morning primer sessions observed that both weight -based sessions and running based sessions improve performance markers within a rugby union population compared to no morning activity (Russell et al., 2016). In this investigation an aggressive weight-based protocol was used which involved 5 sets of 10 reps with 75% of 1RM on bench press with a 90s set recovery (Russell et al., 2016). The other modes for the Primer Session involved repeat effort sprints or repeat cycling efforts. Though the authors reported the largest change came from the running-based primer, there may be merit to an investigation using the same running based protocol (6 x 20m shuttle sprint/40m with incomplete recovery) compared to a heavy resistance whole body weight-based protocol as used by Cook et al. (2014).
The aforementioned studies have demonstrated that including various modes of exercise in the morning of competition can improve athletic performance markers later in the afternoon, however; further researcher has also documented a potentiation effect of a pre-competition session up to 48hours before competition (Tsoukos et al., 2018). Indeed, it was recommended by the authors of this particular study to include a weights-based power session 24hours before competition.
Hormonal Status
A main theme in the research behind primer sessions is not only the potentiation of the CNS, but also the hormonal status of the athlete as this has been strongly linked to variance in athletic performance (Crewther et al., 2012). Researchers have demonstrated that salivary testosterone concentrations can be used as a prediction on athletic markers within the elite rugby population (Crewther & Kilduff., 2012). Testosterone follows a circadian rhythm which typically peaks in the morning and steadily declines throughout the waking day (Kraemer et al., 2001). Research has demonstrated that a low volume, high intensity weights session in the morning can offset the natural decline of testosterone levels throughout the day and is therefore an associated contributor to improved performance (Kraemer et al., 2001).
Not everyone responds the same way to the same stimulus. The body will adapt to stress placed on it, however; not all adaptations have the same magnitude. For example, following an eight-week squat strength protocol some athletes might improve their squat strength by 15% while others only improve by 2.5%. This idea of responders and non-responders is also true for primer sessions. There are many examples in the literature whereby a primer intervention led to improved performance in one athletic marker and not another (Ekstrand et al., 2013; Mason et al., 2017). For example, Mason et al. (2017) reported that rugby players improved in upper body power output 1hr 45mins after a primer session though they reported a negative effect on lower body performance. The authors of this study suggested further investigations into the timing of primer sessions (Mason et al., 2017).
There is an agreement in the literature that a primer session can have a positive impact on athletic performance markers via potentiation of the CNS and hormonal status of an athlete. That being said, there is yet to be a standardised protocol for primer sessions and an agreed upon set of athletic markers specific to rugby. Such protocols and markers should be population specific and serious thought should be given as to whether athletic markers or match day key performance indicators should be used to assess the validity of a primer session. The latter might prove too difficult to accurately research, however; investigations should consider a series of studies on the rugby population utilising a primer protocol and researching the effect on both non fatiguing athletic markers (counter movement jump, reactive strength index and 10/ 40m sprint performance) as well as positional key performance indicators (dominant tackles, meters-per-minute etc).
When not to use Primer Sessions
Based on the current literature there are several recommendations to be made with regards to including a primer session within a weekly schedule. That being said, there are real world scenarios and situations that might negate the need for a primer session to improve performance.
Primer sessions should not be considered when:
Athletes have a low training age or are ‘weak’
Movement proficiency is a must in any modality of exercise that is included within a primer session to ensure there is no injury risk and force can be expressed optimally. Furthermore, stronger athletes respond greater to a potentiation effect and therefore a primer session may not benefit weaker athletes’ performance the same way it would stronger athletes (Seitz, 2014).Cultural considerations
A primer session is utilised to improve game day performance, however; there are plenty of other simple ‘wins’ throughout a training week that can make a great impact on game day performance which may be necessary prior to introducing primer sessions. Nutrition and hydration status is an easy ‘win’ which can impact performance. As is limited alcohol consumption prior to game day. If these simple considerations aren’t given priority first, a simple pre-competition session wouldn’t have the same impact that it could. Additionally, primer sessions will not be impactful if players do not respect the training preparation process (late to training and/or not achieving their recommended loads during a regular week etc).In contrast, a team might be in the situation where athletes are outperforming all expectations in every area, without the need of a primer session. In that situation, it may be hard for a head of department to consider making changes to an already successful and excellent environment.
It adds to stress or fatigue
Training time, space and equipment should not be a barrier for professional athletes. However, for semi-pros or amateur athletes who have potentially more outside stressors, it may not be feasible to carry out a primer session on game day due to time availability and/or equipment availability.
Primer Sessions Guidance
That being said, in an ideal situation pre competition primer sessions would be included within a weekly schedule. Guidance for these sessions based on the current literature would be:
Session should take place ~6 hours before the competition
Though a pre-game day primer has been shown to have merit, if performing a primer on the day of competition, there must be adequate time between the session and the competition to maximise the potentiation effect while minimising fatigue.No new moves
Athletes need to be technically proficient with the movements to express optimal force and/or velocity. Furthermore, muscle soreness will be avoided if athletes are performing exercises which they are familiar with.High intensity / low volume / complete rest
Activities need to stimulate the nervous system and as such must be high intensity. Whether the modality is sprinting, weightlifting or ballistic and plyometric work. Volume should be low to avoid fatigue with rest almost complete (3mins+) after each set.Player centred
As previously mentioned, primer sessions are more effective for stronger players with a potentially higher training age. Therefore, the modality of a pre-competition session should involve a conversation with a player provided there is an initial anchoring of the idea and the mechanisms behind a primer session.
Below are some examples sessions of what a rugby primer session could be consist of. This is based on training principles and the current literature on primer sessions:
Primer 1*
Power Clean | 4sets x 2reps @ 60-80% 1RM
Hurdle Jumps | 4 sets x 6 jumps (fast ground contact time/ low hurdles)
Bench Press | 3 sets x 2 reps @ 80%+ 1RM (saving 1-2 reps in reserve)
Primer 2*
Trap Bar Jumps | 4sets x 2 reps @ 20-40% 1RM of TB Deadlift
Drop Jumps to Box | 4sets x 2 reps @ bw
Push Press | 3 sets of 2 reps @ 80%+ 1RM (saving 2+ reps in reserve)
Primer 3*
Sprints | 4 reps to the 22m
Med Ball Vertical Throws | 4 sets x 4 reps @ ~10% bw
Primer 4*
Max Effort Countermovement Jumps | 4sets x 2reps
Bench Press | 5sets x 10reps @ 70% 1RM (90s rest)
*Perform after a specific and appropriate warm up for the activity. Where possible use velocity-based measurements to drive intent.
It is worth noting that primer sessions should consider the broader context of the athletes’ journey where possible, thereby not only contributing to match day performance but also overall athletic development. For example, the fourth example will be suitable for a developing player who has a hypertrophy focus and perhaps on an accumulation phase of training. This aggressive loading pattern has been shown to be effective in priming the CNS and would also complement the overall programme of the developing player. In contrast, the Primer 1 will be better suited to a player who is on a realisation phase of training.
Conclusion
The consensus in current literature regrading pre-competition primer sessions is that this type of training intervention can improve performance in one or more athletic markers via potentiation of the CNS and hormonal status. There is evidence to suggest that rugby players could increase readiness to perform and potentially match performance by utilising a pre competition training session which has high intensity and low volume, however; the timing of such a session and exact protocol requires further research.
Athletes and teams should only consider utilising a primer session as a means to improve match performance if other easy ‘wins’ are achieved.
References
Cook, C.J.,Kilduff, L.P., Crewther, T.B., & West, M.D. 2014. Morning based strength training improves afternoon physical performance in rugby union players, Journal of Science and Medicine in Sport, 17(3).
Crewther, T.B., Cook, J.C., Gaviglio M.C., & Kilduff P.L. 2012. Drawer PS. Baseline strength can influence the ability of salivary free testos- terone to predict squat and sprinting performance. Journal of Strength and Conditioning Research, 26(1) pp 261–8.
Crewther, T.B., Kilduff, L.P., & Cook, C.J. 2012. Relationships between salivary free testosterone and the expression of force and power in elite athletes. Journal of Sports Medicine and Physical Fitness, 52 (2) pp. 221-227.
Ekstrand, L.G., Battaglini, C.L., McMurray, R.G., & Shields, E.W. 2013. Assessing explosive power production using the backward overhead shot throw and the effects of morning resistance exercise on afternoon performance. Journal of Strength and Conditioning Research, 27(1) pp101–6.
Harrison, P. W., James, L. P., McGuigan, M. R., Jenkins, D. G., & Kelly, V. G. 2019. Resistance priming to enhance neuromuscular performance in sport: evidence, potential mechanisms and directions for future research. Sports Medicine, 49(10) pp1499–1514.
Kilduff, L.P., Cunningham, D.J., & Owen N,J. 2011. Effect of postactivation potentiation on swimming starts in international sprint swimmers. Journal of Strength and Conditioning Research, 25(9) pp 2418–2423.
Kraemer, W.J., Loebel, C.C., & Volek, J.S. 2001. The effect of heavy resistance exercise on the circadian rhythm of salivary testosterone in men. European Journal of Applied Physiology, 84 (1/2) pp. 13-18.
Mason, B.R., Argus, C.K., Norcott, B., & Ball, N.B. 2017. Resistance training priming activity improves upper-body power output in rugby players: implications for game day performance. Journal of Strength and Conditioning Research, 31(4) pp913–20.
Russell, M., King, A., Bracken, R., & Cook, C. 2016. A comparison of different modes of morning priming exercise on afternoon performance. International Journal of Sports Physiology,11(6) pp 763-767.
Seitz, L.B., de Villarreal, E.S. & Haff, G.G., 2014. The temporal profile of postactivation potentiation is related to strength level. The Journal of Strength & Conditioning Research, 28(3), pp.706-715
Tsoukos, A., Veligekas, P., Brown, L.E., Terzis, G., & Bogdanis G.C. 2018. Delayed effects of a low-volume, power-type resistance exercise session on explosive performance. Journal of Strength and Conditioning Research, 32(3) pp643–50.
