EFFECT OF SPECIFIC CORE AND STATIC STRETCHING TRAINING PROGRAMME ON MUSKULOSK...
Dan Weaving Student Thesis Conference
1. The effects of complex
resistance training of the
hip flexor musculature on
acceleration performance
in Rugby League players
Daniel Weaving (200875933)
2. Background
Acceleration in Rugby League
• Four accelerations per minute
(Sirotic et al. 2009)
• Forwards- 10 metres
(Gabbett, Jenkins & Abernethy, 2011)
• Backs- 40 metres
(Meir, 1993)
• Tackling performance indicator
(Gabbett, Jenkins & Abernethy, 2011)
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Anatomy of the Hip flexor musculature.
Taken from Andersson, Nilsson &
Thorstensson (1997)
Swing Phase
(Bosch & Klomp,
2005)
Speed
correlates
(Dowson et al.
1998)
Hip Flexion
One study
(Deane et al.
2005)
Focus on hip
extensors (Wiemann
& Tidow, 1995)
4. Aim & Hypotheses
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Hypothesis
Increase in hip flexion strength as a result of complex
training would enhance the acceleration
performance of Rugby League players further than
resistance training only
5. Research Method and Design
Hip Flexion
• Dynamometer
• 60, 270 & 450os-1
• 5 reps
Acceleration
• Standing start
• Timing gates
• 10, 20 & 30m
Pre & Post Test
(15 subjects)
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6-week training protocol
Resistance
Reps
6 (Peterson,
Rhea &
Alvar
(2005)
Sets
4
Complex
Resistance Plyometrics
50 foot
contacts
(Chu, 1998)
Control
No
training
7. Statistical Analysis
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• Paired t-tests
– Pre & Post test data
• One- way analysis of variance (ANOVA)
– Interactions between experimental groups
• Tukeys HSD post hoc
– Multiple comparisons between experimental groups
• 0.05 level of significance
8. Results
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Resistance Training Complex Training Control Group
Measure Pre-test Post test Pre-test Post test Pre-test Post test
10-m time (s) 1.930
(0.15)
1.844
(0.09)
1.932
(0.08)
1.886
(0.08)
1.974
(0.10)
1.984
(0.09)
20-m time (s) 3.278
(0.2)
3.144
(0.14)
3.364
(0.16)
3.192
(0.15)* ¥
3.314
(0.16)
3.374
(0.08)
30-m time (s) 4.552
(0.24)
4.370
(0.21)* ¥
4.641
(0.22)
4.469
(0.21)* ¥
4.604
(0.19)
4.645
(0.16)
9. Results
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Resistance Training Complex Training Control Group
Measure Pre-test Post test Pre-test Post test Pre-test Post test
60o.s-1 HF
TRQ (N.m)
153.1
(51.7)
177.9
(44.1)* ¥
140.9
(25.9)
159.1
(36.3)* ¥
164.4
(53.5)
162.5
(56.2)
270o.s-1 HF
TRQ (N.m)
108.5
(22.7)
119.5
(13.7)
122.8
(36.6)
142.36
(28.2)
100.9
(20.2)
101.0
(21.9)
450o.s-1 HF
TRQ (N.m)
112.7
(48.8)
119.5
(46.0)
111.8
(19.3)
159.0
(36.5)* ¥Ῐ
127.2
(33.7)
123.9
(36.2)
11. Discussion
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Useful for Rugby League players
Forwards
Sprint no
more than
10m (Meir,
1993)
Backs
Increased
frequency of
20m carries
Attacking
plays (Meir,
1993)
12. Conclusions
• Useful training method
• Complex training
– More research needed
• Mechanisms unknown
– 3-D Kinematic Analysis
14. References
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Bosch, F. & Klomp, R. (2005). Running: Biomechanics and Exercise Physiology
applied in Practice. Netherlands: Elsevier
Deane, R.S., Chow, J.W., Tillman, M.D. & Fournier, K.A. (2005). Effects of Hip
Flexor Training on Sprint, Shuttle Run, and Vertical Jump Performance.
[Electronic version]. Journal of Strength and Conditioning Research, 19 (3), pp
615-621
Dowson, M.N., Nevill, M.E., Lakomy, H.K.A., Nevill, A.M. & Hazeldine, R.J. (1998).
Modelling the relationship between isokinetic muscle strength and sprint
running performance. [Electronic version]. Journal of Sports Sciences, 16, pp
257-265
Ebben, W.P. (2002). Complex Training: A Brief Review. [Electronic version].
Journal of Sports Science and Medicine, 1, pp 42-46
15. References
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Gabbett, T.J., Jenkins, D.G. & Abernethy, B. (2011). Correlates of Tackling
Ability in High-Performance Rugby League Players. [Electronic version].
Journal of Strength and Conditioning Research, 25 (1), pp 72-79
Novacheck, T.F. (1998). The biomechanics of running. [Electronic version]
Gait and Posture, 7, pp 77-95
Meir, R., Arthur, D., & Forrest, M. (1993). Time and motion analysis of
professional rugby league: A case study. Strength and Conditioning
Coach, 1, pp 24 – 29.
Peterson, M.D., Rhea, M.R. and Alva, B.A. (2005) Applications of the dose-
response for muscular strength development: a review of meta-analytic
efficacy and reliability for designing training prescription. [Electronic
version]. Journal of Strength and Conditioning Research, 19, 950-958.
16. References
Change the way you think about Hull | 7 October 2009 | 16
Sirotic, A., Coutts, A.J., Knowles, H. & Catterick, C. (2009). A comparison of match
demands between elite and semi-elite rugby league competition. [Electronic
version]. Journal of Sports Sciences, 27 (3), pp 203-211
Wiemann, K. & Tidow, G. (1995). Relative activity of hip and knee extensors in
sprinting- implications for training. [Electronic version]. New studies in
Athletics, 10, pp 29-49
Editor's Notes
Hello, my names Dan Weaving and I’m here to talk to you today about my study which has focused on the effects of complex resistance training of the hip flexors on acceleration performance in Rugby League players.
The aim of the current study was to investigate the effects of a complex resistance training protocol on acceleration performance in Rugby League players.
We hypothesises that an increase in hip flexion strength as a result of complex training would enhance the acceleration performance of Rugby League players further than resistance only training.
Within our research design we recruited 15 student Rugby League players who were currently participating in the Super 8 competition.
Hip flexion strength and acceleration speed was tested pre and post intervention to measure changes following the two training protocols. Hip flexion strength was tested on the isokinetic dynamometer in a standing functional position related to sprinting at 3 different contraction speeds which are shown here. Subjects completed 5 repetitions at the three different speeds. Acceleration speed was measured via electronic timing gates for 30 metres from a standing start with gates positioned at 10, 20 & 30 metres with subjects allowed two attempts to achieve their best sprint time.
Subjects were then placed into one of three experimental groups; resistance only, complex (combination of plyometric and resistance exercises within the same session) or control (participated in no training). The training groups participated in a 6 week hip flexor programme which consisted of two sessions per week.
The first group performed resistance only exercises which consisted 4 sets in total per session. A total of 8 sets per week has previously been suggested to be an optimal volume per muscle group. Each set consisted of 6 repetitions which has been suggested to be an optimal load for strength development. The complex training group consisted of the same resistance training plan as the resistance only but plyometric exercises were added as a superset with each exercise. Beginners volume according to Chu should be around 100 foot contacts, but as the subjects were also participating in resistance exercises it would be reasonable to half the number of foot contacts. 5 subjects were placed in the control group who participated in no hip flexor resistance training which helped to distinguish any change following the intervention and to also account for maturation of the subjects.
Paired t-tests where used to measure statistical significance between the pre and post test data for all dependent variables and training groups. A one-way ANOVA was used to determine significant interactions between the experimental groups with a Tukeys HSD post hoc utilised to allow multiple comparisons between the experimental groups. Statistical significance was set at the 0.05 level
This table highlights the means and standard deviations for the dependent variables measured pre and post intervention.
Final subject numbers for each group are presented in the square brackets. For clarity of the presentation only results that were found to be statistically significant were included in the table There were no significant decreases in 10-metre time between all three groups. There was a significant decrease in 20 metre sprint performance following complex training which was significantly different to the control group but was not significantly different to the resistance training group. Both the resistance training and complex training groups improved their 30 metre sprint performance and hip flexion strength at 60os post intervention which was significantly different to the control group. There was however no significant difference in 30 metre sprint performance or hip flexion strength at 60os between the resistance and complex training groups. Significant increase in hip flexion strength at higher contraction velocities of 450os were observed following complex training which was significantly different to both the control and resistance only training groups.
The lack of improvement in 10 metre sprint time conflicts with the same study. A lack of increase in sprint performance at 10m following hip flexor strength training is reasonable, as during the initial 10 metres the stance phase is still a predominant phase within the gait cycle and as such, the hip extensors will be the limiting factor to 10 metre sprint performance, as there is only an increase in hip flexor contribution at higher speeds. Improvements in 30 metre acceleration performance is comparable to the previous literature in untrained subjects. A significant relationship between hip flexion strength and sprint speed was found by Dowson at 30 metres (1998) which supports the increasing contribution of the hip flexors at higher speeds. This improvement could possibly be due to better recovery of the swing leg to enable a more optimal foot placement to enhance propulsion during stance.
So how does this transfer over to Rugby League performance
An increase in 20 and 30m acceleration following resistance training of the hip flexor musculature may enhance the players ability to make more metres per carry following kick returns, especially in backs as they have an increased frequency of 20m + carries. Forwards are rarely required to sprint more than 10 metres which may question the inclusion of hip flexor resistance exercises within training programmes. However, there are periods within a game, such as returning the ball from kick offs which are typically around 20m+ ball carries. Increases in hip flexor strength at low contraction speeds may enable forwards to recover the leg better into contact which may enable more metres to be made and for forwards to dominate the collision which is their primary aim.
It appears from our study and the limited previous research in this area that training of the hip flexors is a useful training method in which strength and conditioning coaches can improve their athletes acceleration capabilities and should be included as part of an athletes resistance training programme. The effects of complex training of the hip flexors on acceleration performance needs more work to establish whether the inclusion of hip flexor plyometric exercises is needed for optimal acceleration development. Further research should look at the progression of foot contacts within the hip flexor plyometric training programme to maintain progressive overload and its effects on acceleration. The mechanisms in which improved hip flexor strength improves acceleration is so far unknown and therefore kinematic analysis prior to and following the training programme would enable initial attempts to clarify the reasons why improved strength of the hip flexors improves acceleration performance.
