Editorial Manager(tm) for Strength and Conditioning Journal Manuscript Draft Manuscript Number: SCJ-D-09-00047R2 Title: Optimising within session training emphasis Short Title: Article Type: Article Keywords: Strength; power; velocity; optimising training; monitor; feedback; dynamometry. Corresponding Author: Mr Aaron Randell, BPhEd, BSc, MSc Corresponding Author's Institution: AUT University First Author: Aaron Randell, BPhEd, BSc, MSc Order of Authors: Aaron Randell, BPhEd, BSc, MSc; John Cronin, PhD; Justin Keogh , PhD; Nicholas Gill , PhD Manuscript Region of Origin: NEW ZEALAND Abstract: Current monitoring practices typically provide retrospective quantification of a resistance training session. That is, the information collected summarises a completed session and is therefore used to modify a subsequent session. When the focus of a conditioning program progresses to the development of power, having dynamometry that allows athletes to gain instantaneous feedback as to power output or velocity of motion may result in more goal-oriented movement that increases the likelihood of transference to on-field performance or at the very least improves the mechanical variable of interest. Opposed Reviewers: Response to Reviewers: Dr. Jeff Chandler Editor-in-Chief Strength and Conditioning Journal Ref: SCJ-D-09-00047R1 Authors: A. Randell, J. Cronin, J. Keogh and N. Gill Title: Optimising within session training emphasis 4th August 2009 Dear Dr. Jeff Chandler Thank you for allowing us to revise the manuscript. We would like to express our appreciation for the valuable comments and suggestions of the referees. We hope that we have adequately addressed the concerns raised by the referees and provided reasonable responses to each individual in the attached letters.

We hope that our revisions fulfil the requests of the reviewers and that the revised manuscript now meets the standards for publication in the Strength and Conditioning Journal. We look forward to hearing from you soon. Ref: SCJ-D-09-00047R1 Optimising within session training emphasis Dear Reviewer 1 Thank you very much for reviewing our manuscript and for your valuable comments and suggestions that have helped us in presenting our information more clearly. Reviewer Comments: I have no further comments for the authors. Ref: SCJ-D-09-00047R1 Optimising within session training emphasis Dear Reviewer 2 Thank you very much for reviewing our manuscript and for your valuable comments and suggestions that have helped us in presenting our information more clearly. We have revised the manuscript according to your comments and suggestions and those of the other reviewers. We believe that we have adequately addressed the concerns raised by the reviewers. Our responses (shown in italic+) to your comments are shown below. We hope that our revisions will meet your standard. We really appreciate your further review of the manuscript. General Comments I want to thank the authors for addressing most of my comments/changes. It is obvious that a lot of effort has been put into the project. As I said before, the paper is a well written comprehensive review of literature and is much improved. Unfortunately, the main issues I have with the manuscript have not been fully addressed. The main problem with this paper is two-fold: 1) I am not convinced that the paper gets to the point in a clear/concise manner. 2) The manuscript needs to offer more practical applications for coaches. The manuscript needs significant work and the reviewer suggests the authors continue to revise the paper to a fit a practitioner's journal. Overall, the manuscript will keep the reader's attention better if it is more concise and should be pared down a bit. The manuscript still reads more like a thesis than an article for the readers of the S and C journal. I realize this is a relatively new and unexplored topic that requires further investigation, but there also needs to be more of a tie in to practitioners. I would feel more comfortable if the article was about 1000 words shorter. One of the challenges of being a good author is not how much you say, but how you say it. I think the whole point of the article is lost because you are trying to present too much material. You have to craft

the article more to the S and C journal by picking and choosing the important points you want to make, supporting them with the literature and then offering some practical applications to professionals in the field. One suggestion that I offer pare down the article is to eliminate the section on plyometrics as it does not belong. It does not seem to connect to the rest of the discussion and could be removed without hurting the overall paper. The first pages of the manuscript should be really clear on how you, as the author(s) are developing the argument for what it is you are presenting. Be clear also on the relevance of what you are studying/presenting. What is the value, what problems will it solve for practitioners, or what new opportunities might be opened? Please make further revisions to the paper to make it more concise and more applicable for the readership of the journal. I think this is necessary for the practitioners reading the Strength and Conditioning Journal. + The section on plyometrics has been removed as suggested. + We agree that while it would indeed be useful to the reader to include practical applications, however we feel at this stage it would be unwise to do so given our research into this area in incomplete and anything we do suggest would be highly speculative. We would rather have empirical evidence behind such statements given the status of the literature in this area. Ref: SCJ-D-09-00047R1 Optimising within session training emphasis Dear Associate Editor Thank you very much for reviewing our manuscript and for your valuable comments and suggestions that have helped us in presenting our information more clearly. We have revised the manuscript according to your comments and suggestions and those of the other reviewers. We believe that we have adequately addressed the concerns raised by the reviewers. Our responses (shown in italic+) to your comments are shown below. We hope that our revisions will meet your standard. We really appreciate your further review of the manuscript. Associate Editor In the first review of this manuscript I noted that it was too long and too geared for research. You have reduced it in size to a degree and have made it clearer but it is still too long, and research oriented. However, I feel it can be fixed by dropping "Plyometrics" and "Hormonal" sections of the paper. Omitting those two sections will not affect the rest of the paper (except a literature re-numbering) and will make the manuscript fit the stated goals of the introduction and help focus the paper. It will also be more applicable to the readership of the journal. In your response to the reviews you state that this review is part of a PhD thesis, and that the next stage is to investigate if feedback is beneficial in resistance training. The literature reviews of a thesis try to cover everything known about the topic, and are not necessarily good review because of that tendency. To be effective a review should focus on the topic. Omission of the two sections I noted will focus this manuscript and make it a better review

+The “Plyometrics” and “ Hormonal” sections have been omitted as suggested.

Optimising within session training emphasis

Randell, A.1, Cronin, J.1 2, Keogh, J1. and Gill, N1.

Aaron D. Randell12 Larcy Rd,Lynmore,Rotorua 3010NEW ZEALAND021 754275aaron.randell@aut.ac.nz

1 Institute of Sport and Recreation Research New ZealandAUT UniversityPrivate Bag 92006Auckland 1020New Zealand

2 Edith Cowan University100 Joondalup DrivePerth 6027Western Australia

*Title Page

Aaron Randell (BPhEd, BSc, MSc) is a doctoral student in Strength and Conditioning at AUT University.

John Cronin (PhD) is a Professor in Strength and Conditioning at AUT University and holds an Adjunct Professororial Position at Edith Cowan University.

Justin Keogh is a Senior Lecturer in biomechanics and physical conditioning at AUT University and is currently the under 105 kg New Zealand strongman champion.

Author Photo

Nicholas Gill (PhD) is the Strength and Conditioning Coach for All Blacks. His current research interests include: Recovery interventions, hormonal changes associated with training, performance enhancement strategies, ergogenic aids and adaptions to strength and power training.

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Optimising within session training emphasis

Randell, A.1, Cronin, J.

1 2, Keogh, J

1. and Gill, N

1.

Aaron D. Randell

12 Larcy Rd,

Lynmore,

Rotorua 3010

NEW ZEALAND

021 754275

aaron.randell@aut.ac.nz

1 Institute of Sport and Recreation Research New Zealand

AUT University

Private Bag 92006

Auckland 1020

New Zealand

2 Edith Cowan University

100 Joondalup Drive

Perth 6027

Western Australia

Manuscript (All Manuscript Text Pages in MS Word format, including References and Figure Legends)

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Optimising within session training emphasis

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Key Words

Strength, power, velocity, optimising training, monitor, feedback, dynamometry

Lead Summary

Current monitoring practices typically provide retrospective quantification of a

resistance training session. That is, the information collected summarises a completed

session and is therefore used to modify a subsequent session. When the focus of a

conditioning program progresses to the development of power, having dynamometry

that allows athletes to gain instantaneous feedback as to power output or velocity of

motion may result in more goal-oriented movement that increases the likelihood of

transference to on-field performance or at the very least improves the mechanical

variable of interest.

Introduction

Most resistance training programs quantify and monitor training stress by calculating

the load x reps x sets, which equates to the volume lifted for a session. This is

appropriate for the strength endurance and strength phases of the conditioning

program where the intention is either to lift heavier loads and/or increase the number

of repetitions lifted at the same load. This type of monitoring is used extensively by

practitioners due to its simplicity and the absence of expensive equipment. However,

when the phase of the conditioning program moves to power development, other foci

may provide better power-specific adaptation. Advances in technology (linear

position transducers, rotary encoders, etc.) now enable the direct measurement of

many kinematic (e.g. velocity) and/or kinetic (e.g. power) variables during certain

resistance training exercises. Whilst this type of data is used effectively to test the

effects of resistance training through assessments, its major benefit may be the ability

to continuously monitor and motivate performance during training (10).

Given that specific training goals change according to individual/positional needs and

the time of the training year, it follows that performance feedback needs to parallel the

specific training focus. If this is the case we need equipment and software that can

give players instantaneous feedback related to the variable of interest during that

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training phase such as movement velocity or power output. This may result in goal-

oriented movement tasks in the gym that increase the likelihood of transference to on-

field performance or at the very least improves the capacity of the individual to

produce the mechanical variable of interest such as power. This literature review

addresses this contention by: 1) briefly investigating the literature on feedback and

where possible relate this to strength and conditioning practice; 2) discussing the

methods that have been used to quantify strength and power training; 3) critiquing

those training studies that have used some form of performance monitoring; and, 4)

suggesting future research directions.

Feedback

The use of feedback to provide information about actions attempted in practice or

training has been identified as one of the key influential variables in the acquisition of

motor skills (4, 28). Although originally focusing on reporting of errors, feedback has

taken on the general meaning of any kind of sensory information provided as a result

of a movement (38). Feedback can be generated from the task itself, classified as

inherent or intrinsic feedback, or it may also be provided from external sources, called

augmented or extrinsic feedback (28, 38, 39).

Augmented feedback provides the subject with information relative to the execution

of the previous movement or action with the objective of enabling modifications to be

implemented so that the level of performance may be improved during succeeding

attempts (28). Augmented feedback can be further classified into two types:

knowledge of results (KR) and knowledge of performance (KP). Both types of

feedback may be delivered verbally or visually and usually occur after the movement

has been completed (28, 39).

Knowledge of results can be defined as giving feedback regarding the outcome of the

movement in relation to the task goal, such as making a basket, hitting a target, or

jumping distance in triple jump. Knowledge of performance consists of information

about the movement pattern that led to the performance outcome concerned, for

example giving specific kinetic or kinematic feedback such as power output, velocity,

or force production during the performance (28, 35, 38, 39, 44, 46). Even though

distinctions have been made between these two classes of augmented feedback, an

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operational distinction between them is sometimes lacking. This may occur where the

task requires the performance of one specific movement pattern that is equal to the

task goal. As a result, feedback about the movement pattern is essentially equivalent

to feedback about the goal achievement. Nevertheless, feedback about the movement

pattern (KP) contains more information than knowledge of results, which only

provides outcome information of the movement. Therefore the informational content

of the feedback is viewed as an important determinant of the success of the ensuing

action (28, 44).

Knowledge of Results

The most common method of augmented feedback used during resistance training

provides knowledge of the results, that is, when the weight is successfully lifted or a

set number of repetitions are completed. This feedback is often provided by a

supervising strength and conditioning trainer. Although it has been suggested that the

increased motivation and competitiveness provided by supervising trainers facilitates

an increased training intensity and therefore strength development (6, 31), the effect

of the feedback itself on the performance has not been thoroughly investigated. A

number of studies have reported the importance of instructions prior to the

performance of a lift or test in order to produce optimal results (3, 25). However,

there is no mention of the use of feedback to support the instructions given.

Knowledge of Performance

Kellis and Baltzopoulos (26) examined the effects of visual feedback on maximum

moment measurements of the knee extensors and flexors during isokinetic eccentric

activations. At angular velocities of 30°/sec and 150°/sec the maximal moments

produced during the feedback trials were found to be 7.2% and 6.4% higher for knee

extension and 8.7% and 9.0% higher for knee flexion. These results are similar to

those reported by Figoni and Morris (11) who examined the effects of visual feedback

during isokinetic knee extension and flexion at 15o/sec. Mean peak torque values of

knee extension under feedback and non- feedback conditions were 156.7 ± 42.5ft-lb

and 139.8 ± 42.3ft-lb respectively, whilst for knee flexion the values were 104.1 ±

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24.0ft-lb and 92.4 ± 21.5ft-lb respectively The use of visual feedback equated to an

increase of approximately 12% in mean peak torque values for both muscle actions.

Graves and James (20) evaluated the effect of concurrent visual feedback on isometric

force output during isometric abduction of the fifth digit. Feedback was provided on

alternate contractions and it was reported that peak output was greater during

contractions under feedback conditions (4.4 ± 0.29kg and 4.1 ± 0.26kg respectively).

From these studies it is apparent that the use of visual feedback can improve

isokinetic and isometric output and therefore would be beneficial when utilised during

movements requiring maximal effort.

Feedback Summary

It is fairly conclusive from motor learning theory and the strength and conditioning

literature reviewed, that feedback in terms of knowledge of performance and

knowledge of results can have a substantial effect on strength and power performance.

Of particular interest is the literature citing improvements in strength and power when

the subjects were exposed to visual feedback. The effects of this type of feedback

during each resistance strength training session is almost totally unexplored and

provides exciting possibilities for improved athletic performance.

Monitoring Training Load/Stress

The monitoring and quantification of an individual’s training load or stress during

resistance training is essential as it can provide information as to the effectiveness of

the training program, identify strengths and weaknesses, and enable the provision of

feedback on both results and performance (5, 36). The ability to monitor resistance

training becomes even more critical with the introduction of periodized training

programs, where the manipulation of numerous training variables is seen as vital to

achieving a number of training goals and to avoid over-reaching and/or over-training

(2, 9, 12, 14).

Periodization is widely acknowledged as crucial to optimizing training responses,

especially when there are numerous distinct training goals (12, 17). It is thought that

strength and power adaptation is mediated by a number of mechanical stimuli,

however, the effect of different combinations of kinematic and kinetic variables and

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their contribution to adaptation is unclear (7, 22). Central to the theory of periodized

plans is the principle of progressive overload, which refers to the practice of

continually increasing the mechanical stress placed on the muscle. This may be

achieved through a number of methods; increasing repetition speed, changing rest

period length between exercises and changing total training volume by altering the

number of repetitions, sets, and exercises performed (12). It is essential to understand

how the manipulation of these various acute program variables and their interactions

affect the performance capability of muscle (1, 8, 16). Therefore as the programs

become more advanced and different training goals are prioritised, monitoring

training becomes increasingly important in establishing the optimal stimulus for

development of specific strength components within a periodized plan (12, 22, 43).

One problem facing strength athletes, coaches, and researchers is how to monitor the

volume and intensity associated with different modes and phases of resistance

training. Unlike aerobic exercise, there is no universally accepted method of

monitoring resistance-training exertion (33, 40). As stated, resistance training

provides a complex model of exercise where factors such as sets, repetitions, rest

periods and type of exercise performed are all subject to variation (33). Because of

this, resistance training is particularly difficult to quantify and to date, no one method

has proven successful in monitoring training output during periodized programs (14).

In the previous section of this review, the literature suggests that feedback during

strength and power assessments may improve performance. A natural progression

would be to constantly monitor each training session in such a manner, which should

result in superior performance gains than a series of sessions in which no feedback is

given. The question of interest therefore is what variables should we monitor? This

section investigates current methods used for monitoring training and suggests future

directions for research in this area.

Training Volume and Training Intensity

Training volume and training intensity are the most common methods of monitoring

both resistance training and testing (12). Training volume is a measure of the total

amount of work performed in a training session. Although total work in a repetition

can be calculated as the resistance force which is equal to the product of mass and

acceleration multiplied by the vertical distance the weight is lifted, other variables

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such as duration, number of sets performed, number of repetitions per set, number of

exercises performed per training session, and frequency (number of training session)

all have a direct impact on training volume (14). Training volume is commonly

expressed as the total product of sets, repetitions and load expressed as a factor of

intensity (%1RM). However, when training for strength and/or power, the use of the

volume of training as a monitoring tool may be considered inadequate because of the

overriding importance of intensity and velocity of movement (33).

One Repetition Maximum (1RM)

Monitoring the intensity of resistance training is traditionally expressed as a specified

percentage of a one repetition maximal lift (12, 16, 41). However, many different

definitions are often presented for intensity, perhaps due to the complex nature of

resistance exercise (16, 41). Intensity for example, can also be defined as a function

of power whereby the amount of work performed during a determined time period

influences the reported intensity, such that a lift performed at a faster velocity will

have a greater exercise intensity (12, 16). The differing definitions can lead to

confusion when comparing different programs and results. In addition the

misinterpretation that may arise when intensity can be used to describe either the

intensity of a single repetition, a set of a certain number of repetitions, or an entire

training session may further confuse the practitioner.

The use of %1RM requires that the maximal strength in various lifts used in the

training program be evaluated regularly, otherwise the percentage of 1RM used in

training will decrease, and therefore the training intensity will be reduced as the

athletes become stronger. Another method for quantifying relative intensity is the use

of RM loads. Based on the most weight that an individual can lift for a prescribed

number of repetitions, RM loads are a convenient method for quantifying the

physiological stress encountered (30, 34, 45). This method allows the individual to

change resistances to stay at the target, thereby eliminating the need to regularly re-

evaluate their 1RM. However, this approach may not be applicable in lifts that

require coordinated movements and optimal power development from many muscles,

such as Olympic lifts where drastic reductions in velocity and power output

experienced in the last repetition of a true RM set may not be conducive to correct

technique and optimal performance gains. Equations are often used to predict the

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1RM from the number of repetitions performed with a submaximal load or to help

determine an RM from the 1RM resistance (12). Unfortunately most of these

equations assume a linear relationship between these variables and in many instances

this is not the case across the spectrum of loads that may be used in training (12).

From a practical perspective, the use of percentages of 1RM to quantify and monitor

intensity may not be the most effective method because of the amount of testing time

required and in many instances the prescribed loads are only an estimate of a

particular intensity (15). Furthermore, it has been shown that training loads/intensities

that have been planned are often poorly executed (27), which may result in

suboptimal performance (33). Also, if we consider intensity to be a measure of how

hard the exercise or workout is, we also need to consider other factors, such as rest

periods between sets, number of repetitions completed in each set, and speed of the

exercise. The combination of all these factors will impact how hard the exercise is

perceived to be. When we also add in other variables such as the training status of the

individual and the impact of residual fatigue during intense periods of training, it

becomes even more complex to quantify the overall intensity of training sessions or

phases (16).

Rating of Perceived Exertion (RPE)

Intensity can also be defined as a percentage of effort thus relying on each

individual’s perceptions of their levels of exertion to determine intensity (32). RPE is

based on the understanding that athletes can inherently monitor the physiological

stress their body is experiencing during exercise (5, 13). The RPE scale translates the

athlete’s perception of effort into a numerical score between 0 and 10 with the goal of

receiving an uncomplicated response that reflects the athlete’s impression of the

workout (5, 33). A number of studies have suggested that a single session RPE rating

can be used effectively during resistance training sessions and that it is a valid

measure of exercise intensity (9, 13, 14, 18, 19, 32, 40, 42).

Session RPE

Day et al. (9) investigated the reliability of the session RPE scale to quantify exercise

intensity during high- (H) (4–5 repetitions at 90% 1RM), moderate- (M) (10 reps at

70% 1RM) , and low-intensity (L) (15 reps at 50% 1RM) resistance training. Session

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RPE was higher for the H than the M and L exercise bouts (6.9 ± 1.4, 5.2 ± 1.5, and

3.3 ± 1.4 respectively) indicating that the performance of fewer repetitions at a higher

intensity was perceived to be more difficult than performing more repetitions at a

lower intensity. These results are similar to those reported by Sweet et al. (42) who

evaluated the use of session RPE whilst training at different intensities (4 reps at

90%1RM, 10 reps at 70%1RM, and 2 sets of 15 reps at 50%1RM). Session RPE

decreased from 6.3 ± 1.4 to 5.7 ± 1.7 and 3.8 ± 1.6 as the percentage of 1RM

decreased from 90% to 70% to 50% respectively. It should be noted however, that

apart from the 50%1RM protocol used by Sweet et al., (42) only one set of each

exercise was performed for both the above studies. Singh et al. (40) evaluated the

effectiveness of utilising session RPE to measure effort during multiple sets of

strength (S) (3 sets of 5 reps at 90% 1RM), hypertrophy (H) ( 3 sets of 10 reps at 70%

1RM), and power (P) ( 3 sets of 5 reps at 50% 1RM) training protocols. The session

RPE was significantly lower for P (3.2 ± 1.4) than for H (6.4 ± 1.6) and S (5.9 ± 1.8),

however no difference was found between S and H. McGuigan et al. (32) also

investigated the effectiveness of using the session RPE scale to measure physical

effort during multiple sets of high- (H) (6 sets of 10 reps at 75% 1RM) and low-

intensity (L) (3 sets of 10 reps at 30%1RM ) resistance training sessions. A

significant difference was observed between the session RPE values for the different

intensity levels (H 7.1 vs. L 1.9). Although only Day et al. (9) and McGuigan et al.

(32) reported reliability statistics (ICC = 0.88 and 0.95, respectively) all the authors

concluded that the session RPE appeared to be a reliable method for quantifying the

intensity of resistance training.

Mean Exercise RPE

Of interest are the comparisons of the session RPE value and the mean RPE of the

individual exercises. Day et al. (9) investigated five exercises (bench press, back

squat, overhead press, biceps curl, and triceps pushdown) with RPE ratings obtained

after each set of the respective exercises. No differences were reported between the

mean RPE value and the session RPE value measured after the completion of each

intensity (high-, moderate-, and low-intensity). In contrast, Sweet et al. (42)

investigated six exercises (bench press, lat pulldown, shoulder press, leg press, bicep

curl, and tricep press) and reported that the session RPE was significantly lower than

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mean RPE for all three of the intensities (90%, 70%, and 50%1RM) suggesting the

session RPE may underestimate the average intensity rated immediately after each set.

Of note, the lifting only component (RPE-LO) of the session was also rated and the

session RPE was significantly lower than the RPE-LO for the 70% and 90%

intensities. Similar findings were reported by Singh et al. (40) using five exercises

(squat, leg extension, bench press, and bench pull) where significant differences

between mean and session RPE values were found for strength (7.9 ± 0.9 and 5.9 ±

1.8) and hypertrophy (7.5 ± 1.0 and 6.4 ± 1.6) protocols. McGuigan et al. (32) only

used two exercises (squat and bench press) and therefore did not report mean RPE

values. However the differences between the two exercises will be discussed later.

The previous conclusions as to the effectiveness of session RPE seem somewhat

problematic given that the session RPE values did not reflect mean RPE measures.

Individual Exercise RPE

The issue of the effectiveness of session RPE is further questioned when the RPE of

the individual exercises are compared to the session ratings. Further analysis of the

results reported by Day et al. (9) revealed that while there were no significant

differences between the session RPE values for each intensity (H, M, and L) and the

mean bench press RPE value or the mean back squat RPE value, significant

differences were found to exist between session RPE values and the mean overhead

press, biceps curl and triceps pushdown RPE value (Figure 1). Although Sweet et al.

(42) reported exercise RPE values (without SD), no analysis was performed to

determine if any significant differences between the values were observed. It was,

however, reported, that although the RPE after each of the different resistance training

exercises increased with increased percentage of 1RM, the RPE at a given percentage

of 1RM varied widely among the six resistance training exercises (Figure 2). Singh et

al. (40) did not report the RPE values for the individual exercises, however a

significant difference was reported in the average RPE values of all five exercises in

the strength protocol compared with session RPE value. Significant differences were

observed in the bench press, shoulder press and leg extension for the hypertrophy

protocol, and significant differences were observed for squat and leg extension for the

power protocol. McGuigan et al. (32) observed a significant difference between the

average RPE value for the bench press exercise and the session RPE value during

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each intensity, however, there was no significant difference between the average RPE

values and the session RPE values for the squat exercise.

There appears to be some uncertainty as to the effectiveness of the session RPE scale

to quantify a resistance training session containing a number of different exercises.

This is evident in all four of the above studies (9, 32, 40, 42) where it is apparent that

that some of the individual exercise intensities seem to be misrepresented by the

session RPE rating. Given a typical resistance training session consists of a complex

arrangement of variables, including the type of exercise performed, it would appear

that whilst session RPE might provide a valid description of the average intensity of

the entire workout, its ability to accurately reflect individual exercises may be limited.

Therefore there appears to be some benefit in further investigating how sensitive

session RPE is to specific exercises within a training session.

Although it has been suggested that the session RPE rating may be used effectively

during resistance training sessions as a measure of exercise intensity, it may be

possible to have two different intensities result in similar perceptions of effort. Fry

(16), in a review of the role of resistance exercise intensity on muscle fibre

adaptations, presented a good illustration. Performing a 1RM versus a 25RM lift

resulted in a maximal effort, such that no further repetitions could be completed at

either load. That is, muscular fatigue had occurred and the completion of another

repetition is impossible. Even though both the 1RM and the 25RM tasks were

maximally difficult, different loads were used, different physiological stresses were

presented, and the long-term training effects were different and it is quite likely that

some individuals would score their RPEs differently. Hence the value of an RPE

where there are different foci within a session (strength versus strength endurance)

seems problematic.

Although RPE may provide a practical method of quantifying training sessions its

value as a tool to either monitor the intensity of specific exercises within a session,

different foci (strength endurance, power etc.), or to effectively influence the outcome

of a session remains uncertain. In addition its role as a source of immediate feedback

after a repetition or a set of exercises appears limited.

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Monitoring Training Load/Stress Summary

The effects of training are related to the type of exercise used, its intensity, and its

volume. Resistance training is particularly difficult to quantify as this type of exercise

cannot be objectively evaluated using physiological global measurements such as

heart rate. This problem supports the need for a valid and reliable method of

monitoring performance output within resistance training. Although the monitoring

of training load and or training intensity may provide useful information as to what

has been completed its value in affecting positive changes within a session or to

quantify and evaluate each session is limited. Therefore it is necessary to develop

monitoring systems that can influence the performance of a training session ensuring

that the intended performance objectives are met. To provide this optimal training

stimulus for adaptation it is hypothesized that monitoring and feedback be provided

after each repetition or at least each set for the entire duration of the training session.

Currently there is a paucity of research in this area.

Practical Applications / Future Research Directions

Current monitoring practices typically provide retrospective quantification of a

resistance training session. That is, the information collected summarises a completed

session and is therefore used to modify a subsequent session. What has been

established however is the value of instantaneous feedback. Therefore the challenge

for strength and conditioning coaches is to instrument equipment that can provide real

time feedback. Thereafter it is choosing when and what to monitor in relation to

athlete needs and the yearly training plan.

What is apparent from the literature is that the strength endurance and strength phases

of the training pyramid are adequately quantified via load, intensity, and volume.

However, the ability to relevantly quantify the power phase is an area that is currently

lacking and requires future investigation.

Although, as shown in Figure 3, the load or the intensity of the load lifted appears to

be an important variable to consider for strength endurance and strength adaptation,

other variables could possibly be of greater importance for power adaptation. That is,

how the load is actually moved may be more significant in developing and explaining

improvements to functional performance (21, 24, 29). Maximum power output is the

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product of optimum force and optimum shortening velocity (12, 47), therefore when

training for power development it would seem intuitive to ensure movement velocity

and/or force output and/or power output for each repetition of an exercise session is

maximised. Also of interest may be the rate of power development as this area

remains relatively unexplored. Furthermore the impulse in 100 or 200 ms may be

important to quantify given the impulse momentum relationship and that deterministic

models detail this as one of the most important variables to improve qualities such as

speed (23, 37). Therefore it would seem logical to monitor the changes in such a

variable.

Traditionally the emphasis on quality of effort has been emphasized for plyometric

training and it is becoming obvious that the effectiveness of a power training program

may in fact be related to the quality of each repetition. That is, if a repetition does not

achieve a high percentage of the maximal power or force output or maximal velocity

possible, its impact on training adaptations may be negligible. By monitoring the

variables identified in Figure 3 during a session and providing instantaneous

augmented feedback the potential power adaptations from a resistance training session

may be enhanced. This would also seem applicable to other kinematic and kinetic

variables, that is if the focus of a resistance program shifts to acceleration, or force

production, improvements may be better realised if both the monitoring and feedback

mirrors this focus. What strength and conditioners practitioners need to determine is

whether the provision of such feedback is reliable and is practically beneficial.

Table and Figure Captions

Figure 1. Session RPE and individual exercise RPE values for high- (H), moderate-

(M), and low-intensity (L) resistance training sessions (* denotes significant

difference between individual and session RPE values). Adapted from Day et al. (9).

Figure 2. Session RPE and individual exercise RPE values for 90%1RM, 70%1RM,

and 50%1RM resistance training sessions. Adapted from Sweet et al. (42).

Figure 3. Quantification of the training pyramid.

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