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Završnik, J.. et al.: Children’s muscle composition: a bibliometrics study… Sport Science 7 (2014) 2: 7‐11 CHILDREN’S MUSCLE COMPOSITION: A BIBLIOMETRICS STUDY
OF LITERATURE PRODUCTION
Jernej Završnik1, Peter Kokol2, Rado Pišot3 and Helena Blažun4
1
Dr. Adolf Drolc Healthcare Center, Maribor, Slovenia
2
FERI, University of Maribor, Slovenia
3
Science and Research Centre of Koper, University of Primorska, Koper, Slovenia
4
Center for International Cooperation,University of Maribor, Slovenia
Original scientific paper
Abstract
Objectives: Unhealthy lifestyles and exercise deficit disorders negatively impact societies in general, as well
as individuals’ health, social, cultural, and physical status and in respect to this matter childhood is a very
sensitive period. Summarizing the research focused in children’s physical exercise behaviour and
consequently in their bodies growth, development, and muscle compositions may provide a snapshot of this
field for the experts dealing with children. Methods: In relation to the muscle composition, sport is of
significant importance and the aim of this paper is to quantitatively analyse the research literature from this
area by using bibliometric analysis. Results: The production of papers was clearly increasing, however it was
published by many different researchers coming from more than 170 institutions, 29 countries, and the
research was published in 70 different journals. The research papers became shorter but on the other hand
there were positive trends in the number of references, number of authors, number of institutions and
countries per paper. Conclusions: This analysis revealed that research in the field of childrens’ muscle
compositions related to sport is increasing; however it is highly dispersed and incoherent; the number of
authors and references per paper are increasing, the average age of references is decreasing and the papers’
production is becoming more international, additionally bibliometrics proved to be a useful tool for those who
need a quick overview of research and its utilisation, and as a starting point for integrative literature reviews
and more exhaustive data, information, and knowledge seeking.
Key words: muscle composition, children, sport, bibliometric
Introduction
Methods
Unhealthy lifestyles and exercise deficit disorders
negatively impact societies in general as well as
individuals’ health, social, cultural, and physical
status. In respect to this matter, childhood is a
very sensitive period characterised by various
dynamic
changes
in
physiological
and
psychological development, as well as the
establishment of healthy or unhealthy behaviour
(Faigenbaum & Myer, 2012), which is further
characterised by alarming proportions of obesity
rates in the young (Harriger & Thompson, 2012).
The research question posed in this paper is
stated in the following form: What is the volume
and scope of literary production in the area of
children’s muscle compositions in relation to
sports research and how are the production
patterns expressed by various bibliometrics’
indicators. In order to answer the above question
we had first to select an appropriate analysis
framework, and we decided on bibliometric
analysis, a known but rarely used method within
the area of sports research. The basic unit of this
kind of analysis is called the “information source”,
which can usually be a journal or a conference
paper but can also be a research report or, in
general, any kind of published written text. The
object of bibliometric analysis is to analyse those
basic units within a given scientific context (field,
discipline, or area) using mathematical and
statistical methods, in the manner of determining
various bibliometrics’ indicators such as the most
prolific entities, features of the information
sources, the rates of literary production over time,
citation counts, or more general patterns such as
the history and structure of a scientific field, the
flow of information, patterns of collaboration
amongst scientists, and the impact of journals
(Pritchard, 1969; Garfield, 2006; de Bellis, 2009).
In this paper we are mainly interested in the
bibliometrics’ indicators enumerated above. Using
the search string “muscle composition child*
Children and adolescents should participate in
moderate-to-vigorous, age appropriate, enjoyable,
and varied physical activities at least one hour per
day and strengthen their muscles and bones at
least three times a week. Adequate exercise when
young improves strength, cardio-respiratory
fitness, and body composition (Pišot, et al., 2004;
Landry & Driscol, 2012). From amongst them body
composition in relation to sport is of significant
importance (Lubans & Cliff, 2011), and therefore
the aim of the present paper is to quantitatively
analyse scientific papers productions within this
area. In the Methods section we briefly introduce
bibliometric analysis and its usage during our
methodological approach. In the Results section
we present a detailed overview of the results and
conclude the paper with the more important
observations and conclusions.
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Završnik, J.. et al.: Children’s muscle composition: a bibliometrics study… Sport Science 7 (2014) 2: 7‐11 sport” we identified 105 valid papers from the
SCOPUS database and for each of these papers,
using a text parser developed by one of the
authors, we extracted data such as: the author’s
institution and affiliation nationality; the year of
publication; number of citations; the total number
of references; the average age of the references;
and the number of pages. These data were then
analysed in SPSS using both descriptive and
correspondence analyses. The most prolific
countries, journals, institutions, authors, source
titles, and most cited papers were identified by
built in SCOPUS analysis tools. Linear regression
was applied for the manner of analysing the
influence of bibliometrics’ indicators on the
number of citations per paper. The automatic
option in the SPSS was used (standard model and
forward step method).
Figure 3 Descriptive features of the papers’ references
(Number of references, citations, and average age of
references)
Figure 2 Descriptive features of papers (Number of
authors, papers, countries, and institutions per paper)
The overall trend of the number of published
papers was positive and is increasing following a
second degree polynomial. Figure 2 presents the
descriptive features of published papers and their
changes over time. It is interesting to note that
the papers became shorter (from 10 to 8 pages),
whilst the other papers’ descriptive characteristics
exhibited a positive trend, for example the number
of authors increased from 2 to 5. Papers also
became more inter-institutional (early papers were
written by authors from one institution, recent
papers have been, on average, written by authors
from two institutions. Additional analysis showed
that papers also become more international,
meaning that some recent papers have been
written by authors coming from two or three
different countries. The black lines represent the
trends regarding the descriptive features of the
papers. Figure 3 presents another set of basic
paper descriptive features. We can see that the
number of references per paper increased over
time, their average age decreased slightly and the
trend regarding the number of citations had a
parabolic shape with the highest peak value
around the year 1993 when, in average, the
papers were citied more than 60 times. The black
lines represent trends of each descriptive feature
of the papers’ references. Tables 1 and 2 present
the most prolific institutions and countries. The
most prolific institutions have been located mainly
in Europe and the United States and the most
prolific countries have come from three continents
(USA, Europe, and Australasia) with the majority
of the papers published in the United States. The
most prolific source titles are “Medicine and
Science in Sports and Exercise” (17 papers),
“Journal of Sports Medicine and Physical Fitness”
and “Journal of Sports Medicine and Physical
Fitness” (5 papers), “Clinics in Sports Medicine”
and
”Sports
Medicine”
(4
papers),
and
”International Journal of Sports Medicine” and
”International Journal of Obesity” (3 papers).
From Figure 1, we can see that the first papers
within the area of interest were published in 1973,
and the paper production remained quite small
(zero or one paper), except in the years 1984 and
1986 until the year 1997, when the number of
papers started to increase.
Altogether 105 papers were published under 70
different source titles, expressing the greater
dispersion of literary production in the field of
study. The most cited papers are presented in
Table 3. We can observe that papers have been
highly cited, indeed one has almost 300 citations.
Results
Figure 1 Number of papers per publishing year
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Završnik, J.. et al.: Children’s muscle composition: a bibliometrics study… Sport Science 7 (2014) 2: 7‐11 Table 1 Most prolific institutions
Institution
Table 2 Most prolific countries
Country
Number of
papers
Universidad de Las Palmas de G.Canaria
Spain
6
University of Exeter
UK
5
Universidad de Zaragoza
Spain
4
The College of New Jersey
USA
3
Universite Blaise Pascal
France
2
Malmo University Hospital
Sweden
2
Christian-Albrechts-Universit Kiel
Germany
2
Aristoteleion Panepistimion Thessalonikis
Greece
2
University of Otago
N.Zealand
2
Deakin University
Australia
2
University of Nebraska at Omaha
USA
2
Liverpool John Moores University
UK
2
Lunds Universitet
Sweden
2
Cincinnati Children's Hospital Med Center
USA
Kobenhavns Universitet
Denmark
2
McMaster University
Canada
2
Number of
SciMago
Percentage
papers
country rank
USA
38
36,19%
1
Spain
10
9,52%
9
Australia
8
7,62%
10
U.Kingdom
8
7,62%
2
Canada
7
6,67%
8
Germany
6
5,71%
3
Denmark
4
3,81%
22
France
4
3,81%
5
Italy
4
3,81%
6
N.Zealand
4
3,81%
29
Sweden
4
3,81%
16
92,38%
Country
The most cited papers were, on average, older
(between 1986 and 2004).
Table 3 Most cited papers
Authors
Title
Year
Lohman T.G.
Applicability of body composition techniques and constants for children and
youths
Muscle metabolism and enzyme activities after training in boys 11-13 years
old
Bone mass in prepubertal children: Gender differences and the role of
physical activity and sunlight exposure
Physical fitness and physical activity during adolescence as predictors of
cardiovascular disease risk in young adulthood. Danish Youth and Sports
study. An eight-year follow-up study
The effects of hydraulic resistance strength training in pre-pubertal males
1986
N of
citations
269
1973
96
1998
95
2002
93
1986
91
Strength training for children and adolescents
Regular participation in sports is associated with enhanced physical fitness
and lower fat mass in prepubertal boys
2000
2004
82
74
Resistance training during preadolescence: Issues and controversies
High femoral bone mineral density accretion in prepubertal soccer players
1993
2004
66
63
Applied physiology of swimming
1986
61
Eriksson B.O., Gollnick P.D., Saltin
B.
Jones G., Dwyer T.
Hasselstrom H., Hansen S.E.,
Froberg K., Andersen L.B.
Weltman A., Janney C., Rians
C.B., Strand K., Berg B., Tippitt S.,
Wise J., Cahill B.R., Katch F.I.
Faigenbaum A.D
Ara I., Vicente-Rodriguez G.,
Jimenez-Ramirez J., Dorado C.,
Serrano-Sanchez J.A., Calbet
J.A.L.
Blimkie C.J.R.
Vicente-Rodriguez G., Ara I.,
Perez-Gomez J., Serrano-Sanchez
J.A., Dorado C., Calbet J.A.L.
Lavoie J.M., Montpetit R.R.
It is interesting to note that three from ten of the
most cited papers are from the year 1986. (there
were 6 papers published in 1986, meaning that
half of them received high citation rates)
The associations between words and publishing
years generated by the correspondence analysis
are shown in Figure 4. We could identify some
interesting word-associations:
•
Words “exercise” and “power” were found
together, probably indicating the importance of
exercise for gaining power and managing weight
in children.
•
Words mass, muscle, sport, results, fat,
composition, body, age were clustered together
into complex associative patterns with no clear
structures.
•
Words training, fitness, growth and
performance were grouped together indicating the
importance of training for performance and
fitness, and also growth.
It was also interesting that the words “boys” and
“girls” were found close together meaning that
both of them had similar associations with other
words in the biplot. This observation might
indicate that there had been no large differences
between the sexes within the contexts of the
research on children’s muscle compositions, in
relation to the sports found in the papers analysed
during our study. There were no clear clustering’s
of years, and no patterns that could enable us to
name both dimensions. The world “cloud” as
derived from the paper abstracts presented in
Figure 5 shows that the more used words were
training, physical, body, children, strength, mass,
and muscle. The word frequency analysis showed
that in overall there were no obvious patterns
regarding the word-frequency dynamics but we
could observe some word-frequency peaks, such
as “strength” and “body” in 1985, “children” in
2000, “mass” and “body” in 2004,”activity” and
“physical” in 2007, and “body”, “physical”,
“strength” and “children” in 2011.
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Završnik, J.. et al.: Children’s muscle composition: a bibliometrics study… Sport Science 7 (2014) 2: 7‐11 Figure 4 Biplot of the associations between more
frequent words and publishing years
Figure 5 Word cloud derived from the papers’
abstracts
Using the linear regression model of the
relationship between the number of citations and
the paper’s basic bibliometrics’ characteristics we
found that the number of pages (Informative
importance
=
0.4378),
publishing
year
(Informative importance = 0.3013), and number
of authors (Informative importance = 0.1933) had
the greatest influence covering 93% of overall
Informative importance, however the low model
prediction
power
(R
=
0,2,
information
criterion=635) had to be taken into account. All
the above presented results appertained to the
stated research question.
Discussion
The
bibliometrics
analysis
revealed
some
interesting characteristics of the literature
production on the field of children’s muscle
compositions in relation to sport. The production
of papers was clearly increased but it was much
dispersed.
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In particular, there were many researchers who
came from more than 170 institutions, 29
countries, and had written numerous different
scientific articles published in more than 70
journals; however, it seemed that the observed
research field was slightly incoherent. Additionally,
there was not any indication of constant research
interest that would enable more concrete
professional and scientific development within this
particular field. The increasing number of authors,
institutions, and countries contributing to research
papers showed that the research was complex and
required multidisciplinary and inter-sectional
approaches, as well as teamwork. According to the
bibliometric analysis, the research papers became
shorter but on the other hand there were positive
trends in the number of papers and the number of
authors per paper, meaning that there was
growing research interest in the field of childrens’
muscle compositions in relation to sport.
Additionally,
the
researchers
were
also
increasingly interconnected at the national as well
international levels. Due to this fact it is quite
logical that the number of references per paper
increased; however the more cited were slightly
older papers. This analysis showed that the mostly
cited article was published in the year 1986 (cited
269 times) which may be due to the fact the paper
is almost 20 years old. It was clear from the
methodological point of view and it presented
significant results as they were published in highly
recognised journal etc.The chaotic dynamics
patterns of word-frequencies observed during
frequency and correspondence analysis indicated
that the research interest was insufficiently
focused as the research topics were constantly
changing. The analysis showed that during the
earlier research stage there had been more
emphasis on topics “strength and body”, then the
focus changed to “mass and body”, and “physical
activity”, and finally to “body and strength” in
combination with “physical and children”. The
different research emphases were more or less
logical due to the reduction in physical activity,
irregular eating habits of the children, and
consequently the increasing number of obese
children (Faigenbaum & Myer, 2012; Harriger &
Thompson, 2012).
Conclusion
The presented study revealed that bibliometric
analysis is a very useful tool for the quantitative
analysis of papers’ production and that the results
presented in this paper could be an excellent
starting-point for integrative literature reviews and
more
exhaustive
data,
information
and
knowledge-seeking within the field of children’s
muscle compositions in relation to sport.
Additionally, the research focus, especially on
topics within the field of children’s muscle
compositions in relation to sport was constantly
changing and this fact might indicate that more
focused and coherent research studies are needed
in near future.
Završnik, J.. et al.: Children’s muscle composition: a bibliometrics study… Sport Science 7 (2014) 2: 7‐11 References
de Bellis, N. (2009). Bibliometrics and Citation Analysis. Lanham, Maryland, Toronto, Plymouth, UK: The
Scarecrow Press, Inc.
Faigenbaum, A.D., & Myer, G.D. (2012). Exercise Deficit Disorder in Youth: Play Now or Pay Later. American
College of Sports Medicine, 11(4), 196-200.
Garfield, E. (2006). The History and Meaning of the Journal Impact Factor. Journal of American Medical
Association, 295(1), 90-93.
Harriger, J.A., & Thompson, K.J. (2012). Psychological consequences of obesity: Weight bias and body image
in overweight and obese youth. International Review of Psychiatry, 24(3), 247-253.
Landry, B., & Driscol, S. (2012). Phisycal activity in children and adolescent. PM and R, 4(11), 826- 832.
Lubans, D., & Cliff, D. (2011). Muscular fitness, body composition and physical self-perception in
adolescents. Journal of Science and Medicine in Sport, 14(3), 216-221.
Pišot, R., Kerševan, K., Djordjević, S., Medved, V., Završnik, J., & Šimunič, B. (2004). Differentiation of
skeletal muscles in 9-year-old children. Kinesiology, 36(1), 90-97.
Pritchard, A. (1969). Statistical bibliography; an interim bibliography. SABS, 5, 184-244.
MIŠIĆNI SASTAV KOD DJECE: BIBLIOMETRIJSKO ISTRAŽIVANJE
PRODUKCIJE U LITERATURI
Sažetak
Ciljevi: nezdravi stil života i poremećaji kaop i deficit vježbe negativno utjeće na društvo u cjelini, kao i na
zdravlje pojedinca, socijalno, kulturno i fizičko stanje te je u odnosu na ovo pitanje djetinjstvo vrlo osjetljivo
razdoblje. Rezimirajući istraživanja usmjerena u ponašanju prema dječjem tjelesnom vježbanju, a time i na
njihov rast tijela, razvoj i kompoziciju mišića, moguće je dati pregled tog područja za stručnjake koji se bave
djecom. Metode: U odnosu na sastav mišića, sport je od velikog značaja i cilj ovog rada je kvantitativno
analizirati znanstvenu literaturu iz tog područja pomoću bibliometrijske analize. Rezultati: produkcija članaka
očito je u porastu, i objavljivanje je od strane mnogih različitih istraživača koji dolaze iz više od 170
ustanova, 29 zemalja, a istraživanja su objavljena u 70 različitih časopisa. Znanstveni radovi postaju kraći,
ali s druge strane postoje pozitivni trendovi u broju referenci, broju autora, broju institucija i država po
članku. Zaključak: Ova analiza pokazala je da su istraživanja na području sastava dječjih mišića vezana uz
sport u porastu. No istraživanja su jako je raspršena i ponekad nesuvisla. Broj autora i reference po članku
su u porastu, prosječna starost referenci se smanjuje i produkcija radovi postaje međunarodna. Kako se vidi,
postoje alati za one koji trebaju brzi pregled istraživanja i njegovog korištenja, te kao polazište za
integrativna mišljenja iz stručne literature, iscrpnije podataka, informacije i traženje znanja.
Ključne riječi: sastav mišića, djeca, sport, bibliometrija
Received: April 23, 2014
Accepted: December 20, 2014
Correspondence to:
Peter Kokol
Faculty FERI
University of Maribor
2000 Maribor, Smetanova ulica 17, Slovenia
Phone: +386 2 220 7457
E-mail: peter.kokol@um.si
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