Clark et al.

Sports Medicine - Open (2018) 4:32

https://doi.org/10.1186/s40798-018-0150-3

ORIGINAL RESEARCH ARTICLE Open Access

Contemporary perspectives of core stability

training for dynamic athletic performance:
a survey of athletes, coaches, sports science
and sports medicine practitioners
David R. Clark1* , Michael I. Lambert2 and Angus M. Hunter3

Abstract
Background: Core stability training has grown in popularity over 25 years, initially for back pain prevention or
therapy. Subsequently, it developed as a mode of exercise training for health, fitness and sport. The scientific
basis for traditional core stability exercise has recently been questioned and challenged, especially in relation
to dynamic athletic performance. Reviews have called for clarity on what constitutes anatomy and function of
the core, especially in healthy and uninjured people. Clinical research suggests that traditional core stability
training is inappropriate for development of fitness for heath and sports performance. However, commonly
used methods of measuring core stability in research do not reflect functional nature of core stability in uninjured,
healthy and athletic populations. Recent reviews have proposed a more dynamic, whole body approach to training
core stabilization, and research has begun to measure and report efficacy of these modes training. The
purpose of this study was to assess extent to which these developments have informed people currently
working and participating in sport.
Methods: An online survey questionnaire was developed around common themes on core stability training
as defined in the current scientific literature and circulated to a sample population of people working and
participating in sport. Survey results were assessed against key elements of the current scientific debate.
Results: Perceptions on anatomy and function of the core were gathered from a representative cohort of
athletes, coaches, sports science and sports medicine practitioners (n = 241), along with their views on
effectiveness of various current and traditional exercise training modes. Most popular method of testing
and measuring core function was subjective assessment through observation (43%), while a quarter (22%)
believed there was no effective method of measurement. Perceptions of people in sport reflect the scientific debate,
and practitioners have adopted a more functional approach to core stability training. There was strong support for
loaded, compound exercises performed upright, compared to moderate support for traditional core stability exercises.
Half of the participants (50%) in the survey, however, still support a traditional isolation core stability training.
Conclusion: Perceptions in applied practice on core stability training for dynamic athletic performance are aligned to a
large extent to the scientific literature.
Keywords: Core, Stability, Dynamic, Trunk, Athletic, Performance, Loaded, Functional, Compound, Exercise

* Correspondence: d.r.clark@ljmu.ac.uk
1
School of Sport and Exercise Sciences, Faculty of Science, Liverpool John
Moore’s University, 102, 2 Moorfields, Liverpool L2 2BS, UK
Full list of author information is available at the end of the article

© The Author(s). 2018 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made.
Clark et al. Sports Medicine - Open (2018) 4:32 Page 2 of 10

Key points articles [1, 6, 7, 12–14]. Reviewers have noted that re-
search cannot progress this topic effectively until there
 Core stability training for healthy and athletic is a standardised agreement on the anatomical structure
populations has recently been questioned and and function of the core [1, 6, 7]. A further limitation re-
challenged in scientific literature. The narrow ported by most reviewers is the absence of a valid and
definition of both the anatomy, spinal region reliable test of core function [1, 12]. As a result most re-
between pelvis and diaphragm, and the method of search on the topic is methodologically limited [12, 13]
training the core through the isolation of muscles in and therefore ineffective in confirming or challenging
this region does not relate to full body core function the concept and practice of CST for health and per-
that characterises dynamic athletic performance. formance. A case has been made in the literature for
 The survey reveals that this is reflected in opinions a more functional definition of anatomy of the core,
of people working and participating in sport. Half applicable to healthy and athletic populations [1, 8].
of the participants identified the area between and Similarly, it is proposed that the description of core
including the pelvic and shoulder girdles as the core. function is revised to encompass normal healthy and
Majority supported functional loaded exercises such athletic human movement [8].
farmer’s walk (87%) and barbell squats (84%) as Several comprehensive reviews over the last decade
effective exercises for the development of core have examined the research on the effectiveness of
stability. various CST methods for athletic performance [1, 6, 7,
 Despite the support for a more functional approach, 12–14]. Reviews covered the variations in CST including
selected traditional core stability training methods instability training, trunk rotation exercises, functional
do retain a certain amount of support; isometric training and exercise intensity. Martuscello et al. pro-
plank exercise (56%) and unstable stability ball posed a five core exercise classification system based on
exercises (41%). Many respondents (42%) felt that their review of the research [6]. The categories were
core function should be measured subjectively traditional core exercise (sit-ups), core stability exercises
through observation of sporting and or exercise (isometric plank), ball or device exercises (stability ball),
performance. free weight exercise (squat and deadlift) and noncore
 Trunk is the preferred name of the anatomical free weight exercise (upper body). In a recent study con-
region for almost half (45%) the participants while ducted in an applied performance sport setting, Spencer
35% supported the term core. et al. proposed a comprehensive spinal exercise classifi-
cation [2]. The classification incorporated static and
Background dynamic exercises that were either functional or
The absence of a universally accepted definition of core non-functional according to spinal displacement across
stability (CS) is well noted in the scientific literature [1–8]. four physical outcomes: mobility, motor control, work
A number of these publications have proposed a defin- capacity and strength. Both studies [2, 6] clarify the
ition, focussing either on function, anatomical constitu- range and nature of core stability exercises used in
ents of the core or both. Several reviews have questioned the literature and practice; however, there is concern
and challenged core stability training (CST) for prevention that many core stability intervention studies are di-
and treatment of back pain [9–11] and for improvement luted by other exercises and activities preventing a
of function and performance in healthy and athletic popu- clear assessment of impact of CST [7, 12, 13]. Fur-
lations [1, 5–7, 12–14]. There is a view [1, 7] that CST in thermore, in athletic populations, a reductionist ap-
its current form evolved from clinical research [15] in proach or selective activation to improve integrated
the 1990s. The application of a clinical exercise function is unsubstantiated [1, 2, 7, 12].
approach in healthy and athletic populations has been The proposed protection against injury and improved
criticised, primarily on the basis that teaching an iso- athletic performance from CST has been the subject of
lated muscle pattern in uninjured athletes is unfounded many research studies and review papers. Silfies et al. con-
[6, 10, 16]. Despite this, CST as an intervention spread cluded that following a review of 11 studies, there was
to all exercise disciplines across clinical, fitness and limited evidence to support the use of CST to prevent
sports performance settings with significant commer- upper extremity injury and improve athletic performance
cial interest and support [14]. [3]. The authors questioned whether performance in core
Most review articles on this topic recognised that the stability tests reflected physical or athletic capability and
application of traditional CST in healthy and athletic level of conditioning, rather than solely core stabilization.
groups lack scientific justification [3, 7, 14, 17]. This re- Tests included the isometric front and side bridge,
sulted in a body of research investigating CST in healthy single-leg raise [10], star excursion test [11] and closed
populations [18–22] along with aforementioned review kinetic chain upper extremity stability test [12]. A
Clark et al. Sports Medicine - Open (2018) 4:32 Page 3 of 10

systematic review conducted by Prieske et al. [12] con- athletic events. Researchers have begun to investigate
cluded that CST compared with no training or regular trunk muscle activation in a number of dynamic, loaded free
sports-specific training does improve trunk muscle weight exercises to determine their suitability for the devel-
strength measured predominantly by isometric plank. opment of dynamic trunk strength and stability [29–37].
However, increases in trunk muscle strength only had a Surface electromyography methodology shows there is
small effect on physical fitness and athletic performance good evidence that loaded exercises performed in a stand-
measures in trained individuals. CST compared to al- ing position are an effective method of overloading the
ternative physical training methods in trained individ- trunk stabilization system in a dynamic manner. While
uals had little impact on trunk muscle strength, several reviewers recognise this development [6, 7, 14], it
physical fitness and athletic performance measures. is best summarised by Wirth et al. (2016), ‘… we recom-
Both studies strongly suggest that high levels of gen- mend the use of classical strength-training exercises as
eral fitness are associated with better performance in these provide the necessary stimuli to induce the desired
CS tests and therefore a lower risk of injury and bet- adaptations.’
ter athletic performance test scores [3, 12]. The flawed foundations of CST for dynamic athletic
Separating the core into smaller local and larger performance have been exposed in the scientific litera-
global muscles has little bearing on core stability for ture. Research is underway to better understand the
dynamic movement in healthy people. In Lederman’s most effective training methods for the development of
[10] words, this is an anatomical classification with trunk stability. The aim of this survey is to assess the
no functional relevance. The role the core plays in stabilis- current perspectives of CST in the applied sports setting
ing the body is dynamic and responsive to many postural to determine how well scientific literature informs these
challenges that occur in normal movement and complex, opinions. Our hypothesis is that opinions of those who
reactive environment of sport [14]. The concepts of core work and participate in sport will reflect scientific debate
strength and core stability have been reviewed the literature on key core stability training topics.
[1, 5, 23]. Whether these are separate attributes [5] or
whether core strength is required for core stability [23] re- Methods
main unresolved questions [1]. In this context, core The online survey questionnaire (Additional file 1) was
stability is an integrated, functional motor task [7, 24] developed around common themes on core stability as
and training should reflect this according to movement pat- defined in the current scientific literature. The online
terns [14, 24], forces [7, 24] and torque and velocity [8, 24]. survey was created and distributed using Bristol Online
A limitation identified by Prieske et al. [12] was the Survey (BOS) tool (Tower Hill, Bristol, UK). The ques-
lack of validity of tests used in most of the research. tionnaire comprised four sections: anatomy of the core,
Trunk muscle strength in most studies was measured by function of the core, methods of measuring core func-
timed isometric test (prone bridge) which, firstly, does tion and methods of training the core. The survey con-
not reflect force and velocity of movement of dynamic cluded with general questions about the application of
athletic activity [12]. Secondly, CST programmes in core strength training for dynamic athletic performance.
many of the studies incorporated prone plank or similar The survey question on the anatomy of the core is
isometric exercises in the exercise intervention, which based on definitions in the literature. We used the defin-
rendered timed isometric prone plank an inappropriate ition of local and global stabilization of intersegmental
test of trunk muscle strength in these cases. Most spine proposed by Bergmark (1989) [38]; the passive
reviews conclude there is not a valid method of measur- spinal column, active spinal muscles and neural control
ing the effect of CST on trunk muscle strength within unit as described by Panjabi [39]; axial skeleton between
the context of improving dynamic athletic performance pelvic and shoulder girdle including rib cage, spinal col-
[1, 13, 14, 17, 25, 26]. As a result, many researchers have umn and associated muscle and nerves proposed by
resorted to using conventional performance tests such as Behm et al. [8]; and lumbo-pelvic hip complex according
countermovement jump and sprint tests [12, 13, 27]. to Faries and Greenwood [23]. Categories of exercises
The first three levels of Martuscello’s [6] core exercise and selection criteria for CST used in the survey ques-
classification system appear to contravene the estab- tion were drawn from published studies that investigated
lished overload training principle [28] when applied to muscle activation using these manipulations. The ques-
an athletic population. Traditional low load core exer- tion around core strength and core stability were based
cises, minimal range or isometric core stability exercises on reviews of this topic [1, 7].
and ball/device exercises are all characterised by low A pilot survey was conducted using the postgraduate
force, low velocity and restricted range of movement. sports studies group (n = 20) at the University of Stirling.
Hence, these do not represent training overload in prep- The questionnaire was modified according to feedback
aration for activities that characterise most sports and from the pilot survey. Approval for the study was granted
Clark et al. Sports Medicine - Open (2018) 4:32 Page 4 of 10

by the local research ethics committee in accordance with

the Helsinki Declaration (2013) [40].

Participants
The survey was circulated using two methods: shared
with the principal authors’ 700 LinkedIn connections
and sent by email to 220 qualifying contacts. All recipi-
ents were asked to share the survey with all their
contacts that met the criteria of working or participating
in sport.

Statistical analysis
The data analysis was descriptive and frequency was pre-
sented in the tables as number and percentage (n (%)).
Data presented in Figs. 1, 2, 3 and 4 were analysed using
Fig. 2 Responses to a series of questions on the effectiveness of
Kruskal-Wallis test to assess support for each statement selected categories of exercise in developing core stability for
on 5-point Likert scale. Data presented as mean and dynamic athletic performance. Data are reported as mean level of
95% CI. Five-point scale is as follows: 1 = strongly agree effectiveness with 95% CI. 1 = very effective, 5 = not effective at all.
or very effective and 5 = strongly disagree or not effect- Significant differences p < 0.001: a vs c, d, e, f, g and h; b vs c, d, e, f,
g and h; c vs d and f; d vs e, f and h; e vs f; f vs g and h; g vs h. CI:
ive at all. Significant differences were further analysed
confidence interval
using Dunn’s multiple comparison post hoc test. Priori
alpha level of significance was set at p < 0.05.
recreational sport made up 15% while 9% were
Results semi-professional in part-time paid roles.
Participants Responses to all questions were analysed for all re-
The online survey was completed by 241 respondents from spondents (n = 241) and for each of the five demo-
a range of disciplines involved in sport (Table 1). The high- graphic groups. There were no differences between
est return by employment group was received from group responses and total cohort, so data are presented
strength and conditioning coaches (S&CC; 47%) followed and discussed for the total cohort.
by athletes and players (A&P; 17%) and sport medicine The majority (87%) were qualified to degree level or
practitioners and physiotherapists (SM&P; 17%). A quarter higher, 40% had masters or MSc degrees and 12%
of the cohort were involved in sport at university or had doctoral degrees. Most respondents (73%) re-
school level (27%). A similar number (33%) were ported to have a discipline specific professional quali-
working in professional sport, either with full-time fication. Respondents reported to have been working
professional athletes (21%), or elite funded athletes in their specific discipline for an average of 8 years
in institutes of sport (12%). Volunteers working in (range 0–36 years).

Fig. 3 Responses to which criteria should inform exercise selection

Fig. 1 Reported support for a series of statements relating to core for the development of core stability for dynamic athletic
stability and core strength. Data are reported as mean level of performance. Data are reported as mean level of agreement
agreement with 95% CI. 1 = strongly agree, 5 = strongly disagree. with 95% CI. 1 = strongly agree, 5 = strongly disagree. Significant
Significant differences p < 0.001: a vs b, a vs d, b vs d and c vs d. CI: differences p < 0.05: a vs c, a vs d, b vs c, b vs d and c vs d.
confidence interval CI: confidence interval
Clark et al. Sports Medicine - Open (2018) 4:32 Page 5 of 10

Methods of measuring core function

Respondents were asked to identify the most effective
method of measuring core stability in a healthy, unin-
jured person. Almost a quarter (22%) reported that there
was no effective method to test core stability. A number
(43%) of the respondents proposed subjective assessment
of core stability through observation. Of these, 17% sug-
gested observation of sport-specific movement or exer-
cise technique and 26%, observation of ground-based
loaded barbell exercises. Objective assessments were
proposed by 32% and included the timed isometric plank
Fig. 4 Responses to a series of statements relating to ground-based (19%), functional movement screen (9%) and isometric
loaded free barbell exercises and trunk muscle activation. Data are trunk bracing with biofeedback (4%).
reported as mean level of agreement with 95% CI. 1 = strongly
agree, 5 = strongly disagree. Significant differences p < 0.001: a vs b,
Core function and core stability training
a vs d, b vs c, c vs d. CI: confidence interval
Core stability and core strength (Fig. 1)
The majority believed that core strength is required for
Anatomy and name of the core stability (mean 1.9, 95% CI 1.8–2.0, p < 0.001) and far
In response to the question on the anatomical region fewer agreed that these were separate attributes (mean
that comprised the core, half of the respondents (50%) 2.6, 95% CI 2.4–2.7, p < 0.001) (Fig. 1). Most participants
identified the region between and including the pelvic disagreed with the statement that core strength was re-
and shoulder girdles and associated muscles and nerves quired for athletic performance, but not everyday life
(Table 2). Approximately, a quarter of respondents (mean 3.9, 95% CI 3.7–4.0, p < 0.001).
(27%) identified the region between the diaphragm and
pelvic floor and associated muscles and nerves as the The effectiveness of certain exercise categories on CST
core, while for 18%, this was the lumbar spine, pelvis, (Fig. 2)
hip joints and related muscles and nerves. Interestingly, The exercise categories deemed most effective in devel-
more participants (45%) felt that the region should be oping core stability for dynamic athletic performance
called the trunk while 35% supported the term core and were (Fig. 2) squats and Olympic lifts (mean 1.7, 95% CI,
18% preferred torso. 1.6–1.8, p < 0.001) and farmers walk (mean 1.7, 95% CI

Table 1 (A) Employment and (B) education information presented for all respondents (total and group)
Total S&CC A&P SM&P SP&B SC
All respondents 241 114 (47) 42 (17) 41 (17) 24 (10) 20 (8)
A.
Academic, university or school sport role 66 (27) 29 (12) 10 (4) 11 (5) 10 (4) 6 (2)
Professional: full-time paid position, full-time paid athletes 50 (21) 37 (15) 0 (0) 9 (4) 3 (1) 1 (0)
Volunteer, recreational club sport 35 (15) 4 (2) 21 (9) 6 (2) 2 (1) 2 (1)
Elite professional: full-time paid position, funded, amateur 30 (12) 15 (6) 1 (0) 4 (2) 7 (3) 3 (1)
athletes (Institute)
Elite non-professional, part-time, regional or national athletes 30 (12) 16 (7) 5 (2) 7 (3) 0 (0) 2 (1)
Semi-professional: paid part-time position 22 (9) 9 (4) 2 (1) 3 (1) 2 (1) 6 (2)
Other 8 (3) 4 (2) 3 (1) 1 (0) 0 (0) 0 (0)
B.
MSc/Masters 96 (40) 51 (21) 7 (3) 20 (8) 13 (5) 5 (2)
Degree/Hons 84 (35) 41 (17) 17 (7) 9 (4) 7 (3) 10 (4)
PhD 28 (12) 10 (4) 2 (1) 10 (4) 4 (2) 2 (1)
Diploma 27 (11) 9 (4) 13 (5) 2 (1) 0 (0) 3 (1)
Other 6 (2) 3 (1) 3 (1) 0 (0) 0 (0) 0 (0)
Data presented as number and percentage (n (%)) of all respondents. Italics represent the highest response for the column
S&CC strength and conditioning coaches, A&P athletes and players, SM&P sports medicine practitioners and physiotherapists, SP&B sports physiologists and
biomechanists, SC sports coaches
Clark et al. Sports Medicine - Open (2018) 4:32 Page 6 of 10

Table 2 Responses to the question of what (A) anatomic region (Fig. 4). Equally important in this form of resistance
makes up the core and (B) which term best describes this training was correct postural control (mean 2.0, 95% CI
anatomical region 1.9–2.2, p < 0.001). Slow controlled movement (mean
Total 2.8, 95% CI 2.7–2.9, p < 0.001) and increases in velocity
A. (mean 2.6, 95% CI 2.5–2. 8, p < 0.001) of strength train-
The spine and the associated muscles and nerves 5 (2) ing exercises were not seen as important in eliciting
The lumbar spine, pelvic and hip joints and associated 43 (18)
trunk muscle activation in ground-based free barbell
muscles and nerves exercises.
The region between and including the pelvic and 120 (50) Finally, results for the general questions on the appli-
shoulder girdles and associated muscles and nerves cation of core stability exercises are presented on Table 3.
The region between and diaphragm and pelvic floor 65 (27) Most participants (85%) felt that it was appropriate to
and associated muscles and nerves include specific exercises to train core stability in
Other 8 (3) healthy, uninjured individuals. Less than half (45%) felt
B. that it was effective to exercise the core stabilisers in iso-
lation, while a majority (65%) agreed that core stability is
Torso 43 (18)
developed during normal progressive exercise training.
Trunk 108 (45)
Core 85 (35) Discussion
Upper limb 0 (0) Core stability training for healthy and athletic popula-
Other 5 (2) tions has been scrutinised and challenged in recent years
Data presented as number and percentage (n (%)) of all respondents. Italics in scientific literature [6, 7, 10, 13, 41–43]. Descriptions
represent the highest response of the core by anatomic structures are entirely
dependent on the chosen definition of core function [1].
1.6–1.9, p < 0.001). Conversely, support was moderate to The original narrow definition presented in early re-
low for traditional core stability exercises, namely sus- search focussed on the spinal region between the dia-
pended compound exercises (mean 2.2, 95% CI 2.1– phragm and pelvis [44]. This approach identified
2.3, p < 0.001), isometric plank (mean 2.5, 95% CI, muscular and neural dysfunction associated with back
2.4–2.6, p < 0.001), hanging leg raise (mean 2.8, 95% pain. Hence, core function was isolated to this region
CI 2.7–2.9, p < 0.001) and instability abdominal exer- and proposed training intervention isolated the involved
cises (mean 2.8, 95% CI 2.7–3.0, p < 0.001). Partici- muscles. This approach did not transfer to healthy indi-
pants identified two exercise categories that were viduals and athletes where core function is obviously at
more ineffective than effective; abdominal bracing the centre of dynamic movement characterised by force
(mean 3.2, 95% CI, 3.0–3.3, p < 0.001) and sit-ups and velocity through the length of the body [10]. Core
(mean 3.7, 95% CI, 3.5–3.8, p < 0.001). stability described by Fletcher (2016), ‘…is the kinetic

The exercise selection criteria for effective CST (Fig. 3) Table 3 Answer to a series of questions about the application
Correct movement pattern (mean 1.8, 95% CI 1.7–1.9, of core stability
p < 0.001) was identified as most important exercise selec- Total
tion criteria for development of core stability for dynamic Do you think it is necessary to include Yes 206 (85)
athletic performance (Fig. 3). Exercises characterised by specific exercises to train core stability
in a healthy, uninjured athlete’s exercise No 30 (12)
forces that were equal to or greater than the force in the
programme? Do not know 5 (1)
sport or event, were supported by 60% of the cohort
(mean 2.4, 95% CI 2.3–2.5, p < 0.05). Most were either un- Do you think it is possible to isolate Yes 120 (50)
and train the core stabilization system?
decided or disagreed on the importance of velocity of No 82 (34)
movement (mean 2.6, 95% CI 2.5–2.8, p < 0.05) and Do not know 39 (16)
sustained isometric contraction (mean 2.7, 95% CI Do you think it is effective to isolate Yes 89 (37)
2.6–2.8, p < 0.05) in core stability exercises for athletic and train the core stabilization system?
No 108 (45)
performance.
Do not know 44 (18)
Ground-based free barbell exercises and trunk muscle Do you think that the core stability is Yes 157 (65)
automatically developed during normal,
activation (Fig. 4) progressive exercise training?
No 67 (28)
Most participants agreed that increases in external load Do not know 17 (7)
in standing barbell exercises would increase trunk Data presented as number and percentage (n (%)) of all respondents. Italics
muscle activation (mean 2.0, 95% CI 1.9–2.1, p < 0.001) represent the highest response for each question
Clark et al. Sports Medicine - Open (2018) 4:32 Page 7 of 10

link transferring torques between the upper and lower term core strength relates to the overarching nature of
extremities in sporting actions’ [45]. Consequently, the exercise, rather than the impact on or adaptation
constituent anatomy of the core is described in the in the core stabilization system.
literature to reflect, i.e. region between and including While core strength and core stability may well be
pelvic and shoulder girdles and associated skeleton, viewed by some in our survey as separate entities, this
muscles and nerves [1, 8]. Our survey results suggest has yet to be demonstrated scientifically [1]. The selec-
this shift has permeated applied sports setting; half of tion of exercises used to develop core stability for
the respondents agreed with this definition of the healthy function can range from low load, minimal range
core while a quarter identified with the original de- of movement, abdominal bracing exercises to dynamic,
scription, i.e. structures between diaphragm and pelvic loaded resistance exercises [6]. Research has not been
floor including muscles and nerves. able to identify and describe adaptations that occur in
Surveys have been used effectively to assess nutri- muscles responsible for stabilising the core as a conse-
tion knowledge [46] and understanding of scientific quence of different exercise modes [1, 12]. It is recog-
training principles [47] in the workplace. Response nised though that effective core stability is the control of
rate to our survey (n = 241) was good in comparison movement, including high force and high velocity
to similar surveys which gathered information from movement, generated by interaction between axial and
both athletes (Wade et al., n = 57) [48] and people appendicular skeletons [5, 7, 8]. Most survey responses
working in sport (Taylor et al., n = 28) [49], (Durell et disagreed with the statement that core strength was re-
al., n = 137) [47] and (Torres-McGehee et al., n = 579) quired for athletic performance, but not everyday life.
[46]. Furthermore, the representative quality of our This demonstrated alignment with the principle that
cohort is reflected by the spread of respondents, with core stability underpins both healthy function and dy-
33% in full-time professional positions, either working namic athletic performance. In effect core strength and
with professional athletes (21%) or full-time Institute core stability are synonyms and are used accordingly in
of sport athletes (12%). A quarter (27%) were involved the literature [1, 5, 23]. This is reflected in the survey
in sport in an academic setting, either school or uni- question seeking to determine whether core stability and
versity and a quarter (27%) were in non-professional strength are separate attributes. Responses were mixed
roles, either volunteering (15%) or part-time (12%). with just over half (57%) in agreement and the rest ei-
The majority were qualified to degree level (87%) and ther undecided (16%) or in disagreement (27%).
half had postgraduate degrees (52%). Most had an In our survey questions that assessed support for ex-
industry-specific qualification and on average were ercise categories most effective in developing core sta-
well experienced (mean 8 years) in their discipline. bility for dynamic athletic performance, there was
The cohort is therefore representative of people work- clearly more support for functional, loaded exercises
ing and participating in sport. Furthermore, they were (Fig. 2). Squats and Olympic lifts and farmers walk
reasonably well informed, indicating survey results that engage the full kinetic chain. Conversely support
that represent unbiased perceptions of the wider was moderate to low for traditional, non-functional
population. core stability exercises, namely suspended compound
Our survey investigated perceptions around core exercises, isometric plank, hanging leg raise, and in-
stability and core strength (Fig. 1). The majority be- stability abdominal exercises. Two exercise categories,
lieved that core strength is required for stability and namely abdominal bracing and sit-ups, were regarded
far fewer agreed that these were separate attributes. In as ineffective rather than effective, The survey results
a comprehensive review Hibbs et al. [1] concluded that therefore reflect the many reviews that highlighted a
these two terms had yet to be clearly defined, in fact lack of evidence to support traditional CST for healthy
they failed to identify any characteristics that differen- individuals and recommended loaded, dynamic exercises
tiated exercises for core strength and core stability. that engage the full kinetic chain [1, 6, 7, 12–14, 45].
These researchers reviewed studies that investigated Correct movement pattern was identified as most im-
core stability in response to loaded resistance exercises portant exercise selection criteria for development of
and traditional core stability exercises. A later system- core stability for dynamic athletic performance (Fig. 3).
atic review proposed a five-level core exercise classifi- Exercises characterised by forces that were equal to or
cation system that progressed from traditional core greater than force in the sport or event, were supported
exercises to noncore free weight exercises [6]. Inter- by 60% of the cohort. Most were either undecided or
estingly the fourth classification level was free weight disagreed on whether velocity of movement and sus-
exercises defined as ‘dynamic, externally loaded, intent tained isometric contraction were important in core sta-
to activate lower body and core muscles’. Both these bility exercises for athletic performance. Kibler et al.
reviews suggest that the concept of strength in the (2006) accurately describes the exercise criteria for
Clark et al. Sports Medicine - Open (2018) 4:32 Page 8 of 10

effective CST: ‘integrated activation of multiple seg- Most survey respondents (65%) concurred with this by
ments’ providing ‘force generation’ that produces ‘inter- agreeing that core stability is developed through normal,
active movement’ characterised by ‘proximal stability progressive exercise training. The perception in applied
and distal mobility’ [5]. Core stability development is practice conflicts with scientific literature with regards
therefore integral to all dynamic exercise training and effectiveness of traditional core stability exercises for
sports specific movement, while quality of training effect athletic performance. The majority (85%) of survey re-
is determined by specificity of movement, forces and spondents believed that specific exercises were required
velocity. to train core stability and half supported the use of exer-
There is growing evidence in the literature that external cises that isolated trunk stabilisers.
load in free barbell exercises performed in a standing pos- A limitation of the survey was the method of recruit-
ition is related to muscle activation of trunk stabilisers ing participants through email and direct messaging on
[29, 30, 33, 34, 37, 50]. Impact of this stimulus on core sta- an online professional community platform (LinkedIn).
bility in dynamic athletic performance is more difficult to Emails and notifications may have been filtered to spam
demonstrate. In a recent systematic review, Prieske et al. or junk folders and not reached intended participants.
(2016) reported a large effect for CST on trunk muscle Participants were directed to an online survey, which
strength measured by timed isometric plank, compared to may have served as a deterrent. Despite this, the number
no or only regular sports training [12]. When compared and quality of participants was good in comparison to
to alternative training, such as whole-body strength train- similar surveys. A further limitation may well have been
ing, CST had a small sized effect on trunk muscle the inconsistency of prevailing terminology around the
strength. CST had a small sized effect on muscle strength topic of CST and broader area of exercise and fitness.
(e.g. Squat 1RM), a medium sized effect on muscle power Steps were taken to adhere to the most commonly used
(e.g. countermovement jump) and a small sized effect on terms from the scientific literature in the survey.
athletic performance (e.g. 5000 m run time). They con-
cluded that CST for healthy individuals, in the absence of Conclusion
any other fitness training, would increase trunk muscle The survey has provided evidence that a revised, more
strength. However, when combined with other training, functional definition of core function and constituent anat-
such as whole-body strength training, CST is not effective. omy described in the literature is starting to be used in the
They also propose that increases in trunk muscle strength practical setting. Almost half (45%) of the respondents pre-
from CST, has limited effect on physical fitness and athlete ferred trunk as the name for this anatomical region over
performance in trained individuals. Findings from the sur- core (35%). The absence of a valid objective method of
vey indicate that this information has begun to inform ap- measuring core function (22%) means that the most effect-
plied practice (Fig. 4). Most agreed that increases in ive way is through observation (43%) of exercise and ath-
external load in standing barbell exercises would increase letic movement. A quarter (26%) proposed subjective
trunk muscle activation. Equally important in this form of assessment of movement in upright loaded resistance exer-
resistance training was correct postural control. cises as the most effective method of measuring core func-
The survey included a series of questions (yes/no/do tion. This coincides with the strong shift in perceptions
not know) investigating perceptions on the application towards more functional approach to core stability training
of CST for dynamic athletic performance (Table 3). Most for dynamic athletic performance. Loaded exercises in an
(85%) of the cohort felt it necessary to include specific upright position, such as barbell squat and farmers walk,
exercises to train core stability in healthy, uninjured ath- were viewed as effective training methods as proposed in
letes. With reference to traditional CST, two questions the literature [7, 8, 14]. Core stability as an integrated, func-
were asked; whether it was possible to isolate and train tional motor task [7], with training reflecting this according
the core stabilization system, and whether this approach to movement patterns [14], forces [7], torque and velocity
was effective. Half of the group believed that this was [8], appear to be guiding practice in the workplace accord-
possible, 34% felt not and the rest were undecided ing to the survey. These findings along with strong support
(16%). The isolated training approach was regarded as for developing core stability through normal progressive
not effective by 45%, and 37% were supportive. Prieske’s exercise training, means we found in favour of our hy-
review highlighted growing evidence that specific, trad- pothesis. Some support remained for traditional CST
itional CST is ineffective in healthy individual and ath- through specific exercises (85%) and the isolation ap-
letes [12]. They also that reported that regular sports proach (50%). Our findings lead to the following recom-
training and commonly used supplementary training, mendations: Research to continue into efficacy of
such as whole-body strength training, presents superior activating trunk stabilisers through selected sport specific
stimuli, that adhere to the overload training principle and supplementary training modalities, including com-
[28], for development of core stability in this population. pound, loaded strength exercises. Continue to investigate
Clark et al. Sports Medicine - Open (2018) 4:32 Page 9 of 10

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