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Friday 29 July 2016

My Dissertation: THE EFFECTS OF USING RESISTANCE CHAINS ON 1 REP MAX (1RM) SQUATS IN A UNIVERSITY POWERLIFTING TEAM

Hi everyone,

Been a while since I posted something. This has been due to a number of things;

1. Graduation
2. World Universities (ill do a separate post on this and the Worlds)
3. Family birthdays
4. Applying for Jobs

The list goes one. For this month, it has been the quietest on the blog with only 2 posts. Last year I had 10 in July haha.

Anyways, here is the next article all on my dissertation . I hope you enjoy reading it as much as I did performing it :)

This is an overall summary of the whole project.

Enjoy!

PS I have heavily reduced the content in this to try and explain it in the shortest way possible as my diss was 10,000 words (not including references, tables, images, links etc). So if it feels it is missing something then it is.

PPS Blog is just under 60,000 hits so with this post can you share share and share it some more please.



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THE EFFECTS OF USING RESISTANCE CHAINS ON 1 REP MAX (1RM) SQUATS IN A UNIVERSITY POWERLIFTING TEAM


Abstract

Aim: To determine if using resistance chains will cause a significant difference to a Powerlifter’s one rep max (1RM) squat over an intervention of 7 weeks whilst determining if isokinetic strength of the quadriceps muscle increases (Dynamometer (Biodex) leg extension).
Methods: All subjects are males (16) recruited from Teesside University Powerlifting Team subdivided into four categories of Pilot (4), Control (5), Chain (4) and Cross-Over groups (3). SD for all participants' anthropometrics pre-test include height (178.34cm ± 7.04cm), bodyweight (85.07kg ± 11.84kg), age (21.75 ± 2.35) and 1RM Squat (146.97kg ± 27.73kg). Sub-Question is to confirm if reducing the training cycle to 3 weeks will show a strength adaptation without a significant weight gain. P-Value is set at 0.05 statistical significance.
Results: Post intervention results showed improvement in all groups for 1RM Squat. Pilot (131.87kg – 145.63kg), Control (145kg – 155kg), Chain (143.13kg – 160kg) and Cross-Over (161.67kg – 179.16kg). Paired T-Test P-Value results; Chain (p = 0.024), Control (p = 0.022) and Cross Over (p = 0.007) groups all demonstrated significant improvements. Unpaired T-Test showed no significance between groups. Participants' weight difference pre and post-test was insignificant in all groups. Least weight gained was from the Chain group (p = 0.72), most weight gained was the Cross Over group (p = 0.19), however, results still insignificant. Cohen's D showed Chain (d = 2.23), Control (d = 0.4) and Cross-Over (d = 0.62). Cohen's D produced the greatest training effect, smallest being the Control group. Dynamometer results not included due to post-test due external factors.
Summary: Null hypothesis accepted as no significant difference was found between groups due to small population sample. All groups’ participants showed improvements post-test demonstrating that the intervention worked regardless if chains were implemented, however, the most effective method to yield the largest effect was the Chain Training Group.

Intro

Within the literature of sports science, there has been much debate on what is the best suited method to improve maximal strength, especially within a short training intervention. Few studies have shown that a small training intervention is best for central nervous system (CNS) adaptations as others have performed longer studies (Jensen, Marstrand, and Nielsen 2005). One training method to increase strength is called accommodated resistance. It has been shown that using bands and chains (accommodated resistance) can facilitate an athlete’s velocity, power and maximal strength (Rhea, Kenn, and Dermondy, 2009). However, the majority of studies have many limitations such as incorrect training length, a non-sporting population and incorrect technique (Heinecke et al, 2004 and Cronin et al, 2003). The training method devised will remove these limitations and propose an improved methodology for increasing 1RM squats in Powerlifting within this population.


Literature Review

Right there is too much to cover so what I will do is make a separate article oon accommodated resistance related to this article and back link each of them so it makes more sense.

But a brief understanding;

According to Zatsiorsky (2006), "the heaviest weight that is lifted through a full range of joint motion cannot be greater than the strength at the weakest point". The statement is true due to joint angles (Figure below) and individual biomechanics, however, for some, simply performing normal resistance style training, they will not see a huge benefit.  This is when the strength curve, power/force-velocity curve and accommodated resistance come into play.  


Referring to Figure above as force increases, velocity decreases (and vice versa). When chains are added, this will alter the strength curve to a more bell-shaped format thus allowing the athlete to not only increase the force production, but maintain or increase velocity (thus increasing their power output).


The concept of the chains is to try and balance the strength curve and to make it more challenging, especially during the concentric phase as the chains are used to help overload this phase of the movement (Baker, 2009). More importantly, however, is to push through that sticking point of the movement wherever that may be on the strength curve (Elitefts Archives, 2010).  This is referring to producing as much force physically possible and accelerating through a movement.  When using the chains, this will try and force the subject outside their base of support (BOS). It is important for powerlifters to keep the bar over their mid-foot (BOS) to ensure the correct position to produce the maximum amount force as shown in Back Squat Balance picture.  


When using weight (external load) with and without chains, it will have an effect on the subject’s perceived centre of mass (PCOM). The PCOM refers to the subject plus the external load of the barbell. If the PCOM moves outside the BOS (barbell moves away from the midfoot), then the squat will become more challenging (Cleather, 2012). Using chains will enhance this difficulty - they sway so the additional weight is unstable – which in turn puts more emphasis on the synergist muscles to stabilise the movement.




Incorporating chains will increase a lifter’s confidence and ability as when they un-rack the bar it will be at its heaviest, but when they squat down to the bottom, the chains are de-loaded. As the lifter tries to stand up with “x” amount of force for what is on the bar, they will find it very hard to complete the lift with the added chain weight. To compensate, they have to produce more force and they will stand up more explosively.


That's it in brief but a more in-depth article will be released in the coming weeks. Probably 3-5000 word one on chains, bands and accommodated resistance.

Research Questions

  1. To determine if using chains over a three week period increases participants' 1RM for squat? If so, why, and how?
  2. Does using chains increase participants' isokinetic quadriceps strength over a three-week training cycle on the Dynamometer? If so, why, and how?
  3. Sub-Group Analysis of participants’ weight to establish if strength gain causes a significant increase in bodyweight.

Hypothesises

  1. Null Hypothesis: There will be no significant difference between subjects’ 1RM Squat, pre and post intervention with the chains.
  2. Alternative Hypothesis: There will be a significant difference between the subjects’ 1RM squat pre and post intervention after using the chains.

Methods 
Participants

Participants were recruited from a sample of male powerlifters from Teesside University powerlifting club. The eligibility criteria for involvement was they must have a minimum of two years resistance training and have taken part in a powerlifting competition. The participants will not be blinded during the study as they will know if they are part of the chain training group, CTG (n=4) or control group, CG (n=5). All subjects in both groups will not be performing any other lower body training as this could affect results due to recovery and/or overtraining.  The Hawthorn effect will be present as subjects will train as a group to help speed up data collection. Subjects will be at a range of abilities (Novice/Intermediate/Advanced) and individual progression will differ based on their training age (how long they have been training) and training history (what they have been training). 


Participants’ (Pre-Intervention) Data

Testing Group
Anthropometrics and Squat Mean Pre-Intervention
Height (cm)
Bodyweight (kg)
Age
1RM Squat (kg)
Pilot Group
180.75 ± 3.35
83.75 ±8.92
22 ± 1.41
131.88 ± 26.54
Control Group
177.8 ± 7.65
84.80 ± 13.48
21 ± 0.63
145 ± 26.08
Chain Group
181.75 ± 7.79
91.25 ± 5.40
23.25 ± 3.96
143 ± 4.12
Cross-Over Group
171.66 ± 1.70
78.83 ± 14.33
20.66 ± 0.47
161.66 ± 27.18

All participants’ pre intervention data.



 


Experimental Protocol

All subjects will perform a Warm Up (see Appendix 7.0) before the pre-testing session and each intervention training session. They will follow the same training programme for their additional competition lifts. This is to eliminate any change of improvement via another training method. The control group (CG) will be adhering to the same squat programme as the test group, but without using any chains. All participants are competitive lifters who have been coached and are trained to perform maximal effort testing all year round. Throughout the study, all subjects are instructed and under a coach's supervision. The protocol can be found in Appendix 13.0 which specifies sets and reps and percentage of 1RM over each training session during the 7-week intervention period.

To increase lifters' motivation, once groups have been randomly allocated, they will be paired with a lifter of similar ability. This will help push and encourage them more in training and testing sessions, increasing the magnitude of the Hawthorn Effect (McCarney, 2007). In this study, the athlete must squat below parallel which is deemed when the hip crease is below the knee (IPF, 2015). This is to ensure the study matches the same specification as what is expected in competition.






 Apparatus

Equipment
Make
Model
Manufacturers’ details
Weighing scales
Seca
869
Seca Weighing and Measuring Systems, Birmingham, England
Stadiometer
Seca
Leicester Portable Height Measure
Seca Weighing and Measuring Systems, Birmingham, England
Dynamometer
Biodex
System 3
Biodex Medical Systems, New York, USA


Apparatus used from Teesside University.





Equipment used from outside of Teesside University

Equipment
Make
Model
Manufacturers’ details




Olympic Barbell
ESP
Total Power Bar (20kg)

2015 Elite Sports Performance Technologies Ltd,
Barbell Collars
ESP
2.5kg
2015 Elite Sports Performance Technologies Ltd,
Weighted Discs
ESP
2.5kg, 3.75kg, 5kg,10kg, 15kg, 20kg, 25kg
2015 Elite Sports Performance Technologies Ltd,
ESP Rack



Olympic Collar Barbell   Chains (Pair)
ESP



Powerhousefitness
Lifting Combo Rack



2x15kg
2015 Elite Sports Performance Technologies Ltd.

Bodymax

Apparatus used from outside of Teesside University.




Squatting without Chains





Squatting with Chains



                                                                          
















Variables and Concepts

Dependant Variables (DV): Squat 1RM

Independent Variables (IV): Between groups measurement IV (whether they did, or did not, use chains in their intervention).

Control: A trial without using chains but following the same intervention.

Control Variable: No one will be squatting in knee wraps/squat suit as the study is aimed at Raw lifters: See Glossary

Pilot: Squatting without chains (the same as the pilot except no one used for cross-over trial).

Validity: The Squat test is a correct measure of strength for the sport of Powerlifting.


Data Collection Methods

Testing Protocols (Height, Weight, 1RM Squat and Biodex)

All testing protocols are in Appendices 15.0 and are as follows;

  1. Height (Stadiometer)
  2. Weight (Secca Weighing Scales)
  3. 1RM Squat
  4. Dynamometer Biodex Leg Extension

Data Sheets

The following information is for the participants in the study;

  1. Participant Information Sheet (Appendix 4.0)
  2. Participant Recording Sheet (Appendix 6.0)
  3. Borg Scale (Appendix 14.0)
  4. Participant Diary (Appendices 5.0)
  5. Consent Form (Appendix 2.0)
  6. Medical Form (Appendix 3.0)
  7. Warm Up & Cool Down (Appendix 7.0)
  8. Reference to Squatting Cues (Appendix 10.0)
  9. Intervention Protocol (Appendix 13.0)

Warm Up and Cool down

All participants performed the same Warm up before each session and a Cool Down upon completion. The Warm-Up and Cool-Down are shown in Appendix 7.0.


1RM Squat Protocol and Cues

Please refer to "Powerlifting" (Austin and Mann, 2012) and Nuckols (2016) in Appendix 10.0 for a detailed description on how to perform the squat movement as per powerlifting regulations (IPF, 2015). For the experimental intervention, please refer to Appendix 13.0


Subjects will be training to improve their 1RM Squat. Participants are needed for the following sessions (each lasts between 1-2 hours);



Week 1 Pre Test Week: Take Squat Max 1RM and Isokinetic Leg Extension (performed on two days. Minimum 72 hours between tests, same time of day for each participant).



Week 2 De-load week. Training sessions over each week will fall as Mondays/Wednesday/Fridays



Week 3 Start of 3 Week Wave: 

Session 1     55% of 1RM for 8 sets of 2 reps (with 15kg                        chains added) 

Session 2    60% of 1RM for 8 sets of 2 reps (with 15kg chains added) 

Session 3    65% of 1RM for 8 sets of 2 reps (with 15kg chains added) 



Week 4 2nd Week of Cycle:      

Session 1    70% of 1RM for 8 sets of 2 reps (with 15kg chains added) 

Session 2    72.5% of 1RM for 8 sets of 2 reps (with 15kg chains added) 

Session 3    75% of 1RM for 8 sets of 2 reps (with 15kg chains added) 



Week 5 3rd week of Cycle:        

Session 1    77.5% of 1RM for 8 sets of 2 reps (with 15kg chains added) 

Session 2    80% of 1RM for 8 sets of 2 reps (with 15kg chains added) 

Session 3    82.5% of 1RM for 8 sets of 2 reps (with 15kg chains added) 



Week 6 De-load week



Week 7 Re-Test Squat Max 1RM and Isokinetic Leg Extension (performed on two days. Minimum 72 hours between tests, same time of day for each participant).





Data Collection

Data will be collected pre-session, mid-session and post session as defined in the intervention protocol (Appendix 13.0).




Statistical Analysis

Statistical measures to be used include the following; Standard Deviation (SD) of height, weight, age, pre-testing 1RM Squat and pre-testing Biodex. To measure between groups 1RM squats and Biodex results. Paired T-Test will be used to calculate the difference pre and post-test for within each subject group. Unpaired T-test will be used for comparing post-test scores between groups. 95% confidence intervals will be calculated to show the spread of mean pre and post-test. Data may be insignificant on the T-Tests as population size can affect the scoring so Cohen's formula will be used (Cohen, 1988) to find the effect size of the intervention between 2 means along with Effect and Magnitude based inferences to support Cohen’s. Effect size will be using the Hopkins (2009) table utilising a range from trivial to extremely large. Wilks formula will be used to measure differences from implementing (specific to the sport of powerlifting) intervention (Appendix 15.18).


Data Collection Instruments
Software used to analyse the data included Statistical Analysis Software Package (SPPS) and Microsoft Excel.


Ethical Considerations

Before testing could commence, all participants completed a medical form, consent form, participant information sheet, and were made aware of their right to withdraw. The risk of injury has been reduced due to the familiarisation session and the standardised warm up and cool down. This project has been passed by the Teesside Ethics Committee (Appendix 1.0) and the supervisor for the Project.


Results
 Disclaimer

 Due to unforeseen circumstances, no data from the Dynamometer (Biodex) will be shown in the results section. The majority of participants did not partake in the post-test testing session as required due to external factors. This means no data can be compared with the 1RM Squats.


Participants’ Post-Intervention Data



Testing Group
Anthropometrics and Squat Mean Post Intervention

Bodyweight (kg)
1RM Squat (kg)
Control Group
85.32 ± 13.65
155 ± 24.50
Chain Group
91.05 ± 5.70
160 ± 14.84
Cross-Over Group
79.53 ± 14.84
179.16 ± 28.89

 
Participants’ Post Intervention Data - showing means with standard deviations for height, weight, age, and 1RM squat.



 Pilot Group



Control Group

Chain (Experimental Group)


Cross-Over Group




All Group Means Pre and Post Test



Limitations


One of the major limitations was getting enough participants, particularly in each strength category of novice, intermediate or advanced and in each group of Pilot, Control, Chain Training Group and Cross-Over Group. An increase in participants would have produced more results at multiple ability levels (of strength) and interesting data between groups themselves. However, due to external factors, this was not feasible. Regarding performing the study, it is labour and time intensive, as athletes performing 1RM squats require long rest periods between sets to recover adequately (Sakamoto and Sinclair 2006). This may not suit some athletes due to other external commitments, however long rest periods are needed for full ATP-PC re-synthetisation (Harris et al, 1976.).

No measurements were recorded from the lower body. This would have provided some insight if there was any increase in size (from added muscle mass if the participant gained any bodyweight). However, the reason for not using anthropometric skinfolds and measurements is the sport of Powerlifting does not require athletes to be a specific body fat percentage or size. All they need to be able to do is perform the skill of the squat using maximal strength (IPF, 2015). As the results showed, the participants had insignificant weight gain as the strength gain was from neural drive improvement, as opposed to a hypertrophic adaption. Including these parameters to the current study would have been unfeasible due to the time constraints and the original aims.

Conclusions

To summarise this dissertation, there was a significant difference within group measures as discussed. All participants, across all testing groups, improved their 1RM Squat. The most significant difference was the Chain group. To support this, there was a considerable difference in the effect size of the Chain group (Effect Size and Magnitude Based Inferences results concurred) compared to the rest. Performance improved when broken down into kilograms, weight and Wilks, despite no significant change in bodyweight (both within and between groups testing measures). However, the initial null hypothesis has to be accepted as there was no significant difference between groups regarding the effect of the different interventions. The alternative hypothesis is rejected as a result of this. This was due to the lack of participants in each group which ultimately made the confidence intervals unrealistic to achieve a statistical significance, despite all participants improving between 5-30kg.

Recommendations for future research to improve the experimental protocol could entail; more anthropometrics to measure the girth of the lower limbs to determine if there is any increase in muscle size. The incorporation of a tendon meter could be used to assess what the average power output/velocity per repetition is over the same intervention period. A double loop could also be considered when setting up the chain, as this may increase strength. To ensure a positive statistical significance between the groups, a larger sample size needs to be established and guaranteed as well as increasing the number of athletes in each strength category (equal number in novice, intermediate and advanced).  Overall, there was not a between group statistical significance, however, from a coaching perspective on athletic performance, one can see that there is validity with this intervention as no participant received an injury and all improved.


References

Can be emailed out

Appendix

Can be emailed out





Andrew Richardson, Founder of Strength is Never a Weakness Blog





















I have a BSc (Hons) in Applied Sport Science and a Merit in my MSc in Sport and Exercise Science and I passed my PGCE at Teesside University. 
Now I will be commencing my PhD into "Investigating Sedentary Lifestyles of the Tees Valley" this October 2019. 

I am employed by Teesside University Sport and WellBeing Department as a PT/Fitness Instructor.  


My long term goal is to become a Sport Science and/or Sport and Exercise Lecturer. I am also keen to contribute to academia via continued research in a quest for new knowledge.


My most recent publications: 


My passion is for Sport Science which has led to additional interests incorporating Sports Psychology, Body Dysmorphia, AAS, Doping and Strength and Conditioning. 
Within these respective fields, I have a passion for Strength Training, Fitness Testing, Periodisation and Tapering. 
I write for numerous websites across the UK and Ireland including my own blog Strength is Never a Weakness. 
























I had my own business for providing training plans for teams and athletes. 
I was one of the Irish National Coaches for Powerlifting, and have attained two 3rd places at the first World University Championships, 
in Belarus in July 2016.Feel free to email me or call me as I am always looking for the next challenge. 



Contact details below; 

Facebook: Andrew Richardson (search for)

Facebook Page: @StrengthisNeveraWeakness

Twitter: @arichie17 

Instagram: @arichiepowerlifting

Snapchat: @andypowerlifter 

Email: a.s.richardson@tees.ac.uk

Linkedin: https://www.linkedin.com/in/andrew-richardson-b0039278