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.
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
- To determine if using chains over a three week period increases participants' 1RM for squat? If so, why, and how?
- Does using chains increase participants' isokinetic quadriceps strength over a three-week training cycle on the Dynamometer? If so, why, and how?
- Sub-Group Analysis of participants’ weight to establish if strength gain causes a significant increase in bodyweight.
Hypothesises
- Null Hypothesis: There will be no significant difference between subjects’ 1RM Squat, pre and post intervention with the chains.
- 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;
- Height (Stadiometer)
- Weight (Secca Weighing Scales)
- 1RM Squat
- Dynamometer Biodex Leg Extension
The
following information is for the participants in the study;
- Participant Information Sheet (Appendix 4.0)
- Participant Recording Sheet (Appendix 6.0)
- Borg Scale (Appendix 14.0)
- Participant Diary (Appendices 5.0)
- Consent Form (Appendix 2.0)
- Medical Form (Appendix 3.0)
- Warm Up & Cool Down (Appendix 7.0)
- Reference to Squatting Cues (Appendix 10.0)
- 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
Session 2 72.5% 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)
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.
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
Research Gate: https://www.researchgate.net/profile/Andrew_Richardson7
