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Critical Review of The Pose® Running Technique

This is a technical research paper I wrote and maybe of interest to coaches who focus on running technique

A Critical Review of Fletcher, G., Romanov, N., & Bartlett, R. (2008). Pose® Method Technique Improves Running Performance Without Economy Changes. International Journal of Sports Science and Coaching, 3(3), 365-380, (Fletcher, Romanov, & Bartlett, 2008)

Using the Pose® Method technique of running developed by Dr N. Romanov (Romanov, 2002), Fletcher et at. (2008) conducted an intervention study on sub-elite male heel-toe runners.  This research aimed to provide measurements (pre and post testing) on lower-limb kinematics, in particular centre of mass motion during stance and ground reaction force.  This determined the effect on running economy over 2400 meters and assessed if Pose® Method running intervention increased performance from potential biomechanical changes to the subjects’ running style over 2400 meters.  

The study reveals that although not statistically significant, the Pose® Method intervention group improved their mean time-trial times by 24.7 seconds compared to a 3 second decrease in the control group with no significant changes to pre-post economy of effort during the economy run at 3.35 m/s (Fletcher, et al., 2008).  In additional to this Fletcher et at. (2008) also reports significant changes to pre-post intervention regarding stance times, step frequency, centre of mass (CofM) displacement during stance and knee flexion velocity during stance and swing phase.  

This research was conducted as part of a Ph.D. research paper, the results of this study provide an insight into the biomechanical characteristics of the Pose® Method running technique.  This is a well designed and coordinated intervention study on sub-elite male athletes into the kinematic of the Pose® Method of running.  The author has collected comprehensive and accurate biomechanical data on a small group (n=16) of sub-elite male runners allowing for a greater understanding in the effect of this style of running.  The detail included within the paper allows for the study to be accurately replicated by a third party.  The study has produced valid and reliable kinematic data on the Pose® Method of running.  However, several limitations must be considered when interpreting the study findings.

There are some flaws within the research design which could be addressed resulting in an increase in the validation of the results.  The main criticism of the research design is the control groups’ intervention.  The control group was given an intervention and therefore not a truly comparable study group.  The Pose® Method group (n=8) received seven, one hour coaching sessions with experienced Pose® Method instructors.  The heel-toe group who were classed as the “control” group received a self administrated intervention of basic running drills.  Due to the unsupervised nature of this intervention compared to the supervised coached structured session it is difficult to establish the following: to what intensity the heal-toe group trained at, if the drills were performed correctly or if the subjects even completed the drills.  This could affect the outcome of the heel-toe groups’ result, either from an increase in fatigue or recovery, altered biomechanical running style or other psychological adaptations from the running drills.

The paper is part of the first authors’ (G, Fletcher) Ph.D research project.  The authors’ intentions throughout the paper are to investigate the claims that Pose® Method of running intervention on heel-toe runners provides reduced energy cost, reduced effort, and with improved performance (Romanov, 2009).  However, throughout the paper there seems to be an underlying subtle bias towards the Pose® Method of running.  Rather than reporting the results with an unbiased objective viewpoint, it gives the article a feel of reading a marketing pitch for Pose®.  This can be highlighted in the discussion section, when the author reports any observations are considered to be associated with an efficient and economical running style, are followed by an “advertisement” for pose running such as;    The author reports a reduced braking ground reaction force “due to Pose® Method closer CoM impact”, a decrease in vertical oscillation “distinguishable characteristic of Pose® running”, a reduced stance time “characteristic of Pose® running”, an increase in knee flexion velocity “Pose® runners are taught...” and stride length and frequency “Pose® method intervention addresses....”.  This would be less of a criticism if these observations were due to an effective and efficient running technique rather than a manipulated artificially created technique that presents false-positive characteristics.  This perceived bias may be unintentional, however the author (Fletcher) has been involved closely with several articles on the Pose® method and is clearly an advocate of the Pose® method style (Arendse, et al., 2004; Dallam, Wilber, Jadelis, Fletcher, & Romanov, 2005; Korff, Fletcher, Brown, & Romer, 2011; Romanov & Fletcher, 2007).

The main concern analyzing this paper is within the context in which the author discusses the finding with regards the current academic research on running and sprinting biomechanics.  Considering that this is a PhD research paper the author does not consider work of current studies or recent literature regarding the biomechanics of an efficient and economical running gait.  Fifty percent of the references cited within the paper are 30 years+ old.  An example is at the start of the discussion when the author claims that Pose® running displays consistent kinematic changes compared to other studies. The “inconsistent” studies he refers to are over twenty years old and therefore should not be considered recent.  The only current references are derived from other papers which the second and third authors have written or been involved with (Arendse, et al., 2004; Dallam, et al., 2005; Romanov & Fletcher, 2007), and interestingly some of these papers have been openly criticised for poor or misleading biomechanics (Brodie, Walmsley, & Page, 2008).

It is vital to appreciate the characteristics of an efficient and economical running gait to understand the context in which the results of the study have been discussed.  An efficient running gait has been described in recent research as having an optimal stride frequency and vertical impulse amplitude relationship (Bramble & Lieberman, 2004; Williams & Cavanagh, 1987).  Efficient runners display a longer stride with minimal vertical impulse, allowing enough vertical impulse to overcome gravity and reposition the limbs without excessive CoM oscillation, (Cavanagh & Williams, 1982; Heise & Martin, 2001; Saunders, Pyne, Telford, & Hawley, 2004a).  By having a mid-foot / fore-foot initial contact point occurring under the runners CoM, the horizontal braking force is decreased.  By over-striding and having a heel strikes landing further in front of the runners centre of mass the breaking effect is increased and therefore the efficiency is reduced (Chang & Kram, 1999; Kyrolainen, Belli, & Komi, 2001; Slocum & James, 1968).  A short contact time with rapid force generation (Nummela, Keranen, & Mikkelsson, 2007), combined with a fore-foot strike that when compared to a heal strike, reduces the horizontal braking forces and therefore not dissipating energy into the training shoe that occurs with a heel-strike running gait (Lieberman, et al., 2010).  Therefore, minimal CoM vertical oscillation, short contact time, rapid force generation and reduced horizontal braking forces can all be seen as a consequence rather than the cause of an efficient running technique (Kyrolainen, et al., 2001; Kyrolainen, et al., 2003; Kyrolainen & Komi, 1995; Nummela, et al., 2007; Saunders, et al., 2004a; Saunders, Pyne, Telford, & Hawley, 2004b).

The author describes and references several factors attributed to the Pose® Method of running (Romanov, 2002), such as reduced stance time, reduced stance length, increase in step frequency, reduced vertical oscillation, increased knee flexion velocity and reduced braking GRF.  These false-positive efficient characteristics can be exploited and be misleading. The Pose® characteristic of reduced stance time and reduced step frequency is created by a reduced vertical and horizontal impulse. The athlete must overcome gravity and produce a horizontal propulsive force to counter the horizontal braking force with the initial foot contact, resulting in the subject having to accommodate this with an increased step frequency and shorter stride length.  This increase in frequency and reduction in impulse amplitude naturally produces a decrease in vertical oscillation of the subjects’ centre of mass, however the net vertical oscillation remains unchanged.  The author highlights the decrease in vertical oscillation as a positive effect of pose running, whereas in truth a truly efficient running technique would reduction vertical oscillation of the CoM (Saunders, et al., 2004a).  This would be achieved by generating a vertical impulse great enough to overcome gravity, reposition the limbs during the optimum stride length (Cavanagh & Williams, 1982) and consequently utilise the remaining time to produce horizontal propulsion force at the optimum angle without oscillating unnecessary and wasting energy and Increasing oxygen demand (Heise & Martin, 2001).

The Pose® method achieves a reduces in the horizontal braking forces, by creating a fore-foot strike and decreased stride length and contact length.  The initial foot contact that occurs under the CoM is not achieved by a natural optimum stride length or speed (Cavanagh & Williams, 1982).  The author highlights that the Pose® Method has a decreased stance time, a significantly reduced stance length and a significantly increased knee flexion velocity during the swing phase.  These factors are “artificially” created by teaching the athlete to “pull the support foot rapidly from the ground at terminal stance” (Romanov, 2002).  The author reported that, unlike other research that has found a correlation between an increase in stance time and poor economy (Williams & Cavanagh, 1987), this study could not (Fletcher, et al., 2008).  As stance time decreased the correlation with economy changed with the author stating it has no relationship with running economy.  The reason for this observation could potentially be that the Pose® Method stance time is created artificially, compared to a stance time that is a result of the velocity of the CoM horizontally during the contact length/ stance phase (Goodwin, 2011; Weyand, Sternlight, Bellizzi, & Wright, 2000).

 Fletcher et al. (2008) reported that during the economy trial there was no difference between groups, both pre- and post testing, concerning maximum and mean HR and reported RPE scales.  During the time-trial the Pose® group increased performance by a mean time of 24.7 s whereas the heel-toe group decreased by a mean of 3.3 s, although this was not statically significant.  The statistically significance is vital to this validity of this paper, simple because the results could have occurred by chance and fluctuations in the subjects performance (Petrie & Sabin, 2003).  The subjects were selected from personal contact with the author, and had to meet seven very specific criteria: male, sub-elite, heal-toe runners, aged 18-30 years old, injury free for 2 years, with a minimum of two years running history, and unfamiliar with the Pose® Method of running.  The question remains of why were the criteria so specific.  Were the subjects chosen because it was perceived they had the most potential to show a positive improvement for the Pose® Method of running? Or, were the subjects selected due to their athletic performance and perceived high stimulation thresholds required for adaptation, thus causing any results in the Pose® Method group could be attributed to the technique rather than any adaptations from stimulation?  If the latter is the case then statistical significance is crucial to claiming the Pose® Method intervention was responsible for the findings, rather than just chance. 

The non-statistical significance is not unexpected due to the small subject number and the effect of the Pose® Method.  Even though the characteristics of the Pose® Method of running are reduced stride length, increased stride frequency and reduction in CoM vertical oscillation (Arendse, et al., 2004; Dallam, et al., 2005; Romanov, 2002), this does not mean it is an efficient and effective running technique.  If the Pose® Method had improved those aspects of the runners’ technique we would expect to see a statistical significance result which we could confidently attributed to the Pose® Method intervention.  This study highlights the fact that the characteristics promoted by the Pose® Method are a consequence of an efficient running technique and not the cause of an efficient running technique. 

Despite some deficiencies in methodology, this study has provided valid and accurate data on the lower-limb kinematics of the Pose® Method of running.  Fletcher et al. (2008) has extended the body of knowledge into the biomechanics of the Pose® Method of running.  However, the current study is inconclusive and further studies must be undertaken with a wider population of subjects, utilising a larger sample size to improve the understanding concerning the Pose® Method of running.  The real failure of this study is the perceived underlying bias within the discussion and the conclusions the author arrives at with regards other research in the field of running economy. 

References

Arendse, R. E., Noakes, T. D., Azevedo, L. B., Romanov, N., Schwellnus, M. P., & Fletcher, G. (2004). Reduced eccentric loading of the knee with the pose running method. Medicine and Science in Sport and Exercise, 36(2), 272-277.

Bramble, D. M., & Lieberman, D. E. (2004). Endurance running and the evolution of Homo. Nature, 432(7015), 345-352.

Brodie, M., Walmsley, A., & Page, W. (2008). Comment on "Runners do not push off the ground but fall forwards via a gravitational torque" (Vol.6, pp. 434-452). Sports Biomechanics, 7(3), 403-405.

Cavanagh, P. R., & Williams, K. R. (1982). The effect of stride length variation on oxygen uptake during distance running. Medicine and Science in Sport and Exercise, 14(1), 30-35.

Chang, Y. H., & Kram, R. (1999). Metabolic cost of generating horizontal forces during human running. Journal of Applied Physiology, 86(5), 1657-1662.

Dallam, G. M., Wilber, R. L., Jadelis, K., Fletcher, G., & Romanov, N. (2005). Effect of a global alteration of running technique on kinematics and economy. Journal of Sports Sciences, 23(7), 757-764.

Fletcher, G., Romanov, N., & Bartlett, R. (2008). Pose® Method Technique Improves Running Performance Without Economy Changes. International Journal of Sports Science and Coaching, 3(3), 365-380.

Goodwin, J. (2011). Maximum velocity is when we can no longer accelerate. Professional Strength and Conditioning (21), 3-9.

Heise, G. D., & Martin, P. E. (2001). Are variations in running economy in humans associated with ground reaction force characteristics? European Journal of Applied Physiology, 84(5), 438-442.

Korff, T., Fletcher, G., Brown, D., & Romer, L. M. (2011). Effect of "Pose" cycling on efficiency and pedaling mechanics. European Journal of Applied Physiology, 111(6), 1177-1186.

Kyrolainen, H., Belli, A., & Komi, P. V. (2001). Biomechanical factors affecting running economy. Medicine and Science in Sport and Exercise, 33(8), 1330-1337.

Kyrolainen, H., Kivela, R., Koskinen, S., McBride, J., Andersen, J. L., Takala, T., et al. (2003). Interrelationships between muscle structure, muscle strength, and running economy. Medicine and Science in Sport and Exercise, 35(1), 45-49.

Kyrolainen, H., & Komi, P. V. (1995). The function of neuromuscular system in maximal stretch-shortening cycle exercises: Comparison between power- and endurance-trained athletes. J Electromyogr Kinesiol, 5(1), 15-25.

Lieberman, D. E., Venkadesan, M., Werbel, W. A., Daoud, A. I., D'Andrea, S., Davis, I. S., et al. (2010). Foot strike patterns and collision forces in habitually barefoot versus shod runners. Nature, 463(7280), 531-535.

Nummela, A., Keranen, T., & Mikkelsson, L. O. (2007). Factors related to top running speed and economy. International Journal Sports Medicine, 28(8), 655-661.

Petrie, A., & Sabin, C. (2003). Medical Statistics at a Glance. London: Blackwell.

Romanov, N. (2002). Dr. Nicholas Romanov's Pose® Method of running. Miami: PoseTech.

Romanov, N. (2009). Pose Running Technique Characteristics.   Retrieved 26 January 2012, from http://www.posetech.com/pose_method/pose-method-of-running-technique.html

Romanov, N., & Fletcher, G. (2007). Runners do not push off the ground but fall forwards via a gravitational torque. Sports Biomechanics, 6(3), 434-452.

Saunders, P. U., Pyne, D. B., Telford, R. D., & Hawley, J. A. (2004a). Factors affecting running economy in trained distance runners. Sports Medicine, 34(7), 465-485.

Saunders, P. U., Pyne, D. B., Telford, R. D., & Hawley, J. A. (2004b). Reliability and variability of running economy in elite distance runners. Medicine and Science in Sport and Exercise, 36(11), 1972-1976.

Slocum, D. B., & James, S. L. (1968). Biomechanics of running. JAMA, 205(11), 721-728.

Weyand, P. G., Sternlight, D. B., Bellizzi, M. J., & Wright, S. (2000). Faster top running speeds are achieved with greater ground forces not more rapid leg movements. Journal of Applied Physiology, 89(5), 1991-1999.

Williams, K. R., & Cavanagh, P. R. (1987). Relationship between distance running mechanics, running economy, and performance. Journal of Applied Physiology, 63(3), 1236-1245.