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Validity and reliability of body composition analysis using the tanita BC418-MA

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This investigation compared measurements of percentage body fat (%BF) by bioelectrical impedance analysis (BIA) using the TANITA BC418-MA (TAN) with hydrostatic weighing (HW), and skinfold thickness (ST) (Study 1). In addition, the same-day test-retest reliability of the TAN system was assessed (Study 2). For Study 1, a sample of 28 male and 29 female subjects were recruited. TAN, HW, and ST were used to assess %BF with the same experimenter completing all assessments in a counterbalanced order. In Study 2, 24 males and 28 females had %BF measured on two occasions using the TAN to establish the same-day test-retest reliability of the system. Results for Study 1 indicated that TAN and ST recorded significantly different mean %BF compared to HW, with %BF being overestimated by 1.68% using TAN and 1.49% using ST. Despite strong correlations between TAN and HW (r = 0.81; P<0.05) there was relatively poor agreement between the %BF measurements from TAN and HW (±9%), although the level of agreement between ST and HW was little better (±8%). The same-day test-retest reliability of TAN was good with no mean bias from test to test and excellent limits of agreement (<1%). In conclusion, the TANITA BC418-MA is a reliable system, which has poor agreement with laboratory-based methods of assessment (HW). However it is on a par with assessment by skinfold thickness and provides a non-invasive alternative, which requires less operator training.
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74
Journal of Exercise Physiology
online
December 2012
Volume 15 Number 6
Editor-in-Chief
Tommy Boone, PhD, MBA
Review Board
Todd Astorino, PhD
Julien Baker, PhD
Steve Brock, PhD
Lance Dalleck, PhD
Eric Goulet, PhD
Robert Gotshall, PhD
Alexander Hutchison, PhD
M. Knight-Maloney, PhD
Len Kravitz, PhD
James Laskin, PhD
Yit Aun Lim, PhD
Lonnie Lowery, PhD
Derek Marks, PhD
Cristine Mermier, PhD
Robert Robergs, PhD
Chantal Vella, PhD
Dale Wagner, PhD
Frank Wyatt, PhD
Ben Zhou, PhD
Official Research Journal
of the American Society of
Exercise Physiologists
ISSN 1097-9751
Official Research Journal of
the American Society of
Exercise Physiologists
ISSN 1097-9751
JEPonline
Validity and Reliability of Body Composition Analysis
Using the Tanita BC418-MA
John S Kelly1, John Metcalfe2
1University of Chichester. School of Physical and Adventure
Education. West Sussex, England, 2School of Sport, Tourism and the
Outdoors. University of Central Lancashire, Preston, Lancashire,
England
ABSTRACT
Kelly JS, Metcalfe J. Validity and Reliability of Body Composition
Analysis Using the Tanita BC 418 MA. JEPonline 2012;15(6):74-83.
This investigation compared measurements of percentage body fat
(%BF) by bioelectrical impedance analysis (BIA) using the TANITA
BC418-MA (TAN) with hydrostatic weighing (HW), and skinfold
thickness (ST) (Study 1). In addition, the same-day test-retest
reliability of the TAN system was assessed (Study 2). For Study 1, a
sample of 28 male and 29 female subjects were recruited. TAN, HW,
and ST were used to assess %BF with the same experimenter
completing all assessments in a counterbalanced order. In Study 2,
24 males and 28 females had %BF measured on two occasions using
the TAN to establish the same-day test-retest reliability of the system.
Results for Study 1 indicated that TAN and ST recorded significantly
different mean %BF compared to HW, with %BF being overestimated
by 1.68% using TAN and 1.49% using ST. Despite strong correlations
between TAN and HW (r = 0.81; P<0.05) there was relatively poor
agreement between the %BF measurements from TAN and HW
(±9%), although the level of agreement between ST and HW was little
better (±8%). The same-day test-retest reliability of TAN was good
with no mean bias from test to test and excellent limits of agreement
(<1%). In conclusion, the TANITA BC418-MA is a reliable system,
which has poor agreement with laboratory-based methods of
assessment (HW). However it is on a par with assessment by skinfold
thickness and provides a non-invasive alternative, which requires less
operator training.
Key Words: BIA, Body Composition
75
INTRODUCTION
The accumulation of excess adipose tissue in adults is independently associated with an increased
risk for many chronic health conditions, including hypertension, diabetes, coronary heart disease, and
stroke (23,24). Current evidence suggests that this is also the case for children and young adults
(8,10,12). The relationship between body fat (BF) and the risk of chronic disease is stronger for a
centrally distributed pattern of fat deposition compared to that in lower body segments (6,14,17).
Despite the role of abdominal obesity in the development of many chronic diseases and disabilities,
an accurate and reliable assessment of percentage body fat (%BF) is still not readily available outside
of research institutions.
In practical, terms the measurement of %BF or body composition needs to be inexpensive, non-
invasive, operator friendly, and gives highly reproducible and accurate results (2). Assessment
methods that demonstrate the most accurate and reliable results are Computed Tomography (CT),
Hydrostatic Weighing (HW), and Dual-Energy X-ray Absorptiometry (DEXA). Hence, these methods
are considered as reference standards (1,13,25). The problem, however, with the technology is that
they are prohibitive in most practical situations due to high costs and the need for laboratory space,
operator training and experience. In addition, these methods do not eradicate the possibility for
measurement error (11).
Other methods predict body composition using regression analysis against a reference standard.
Although these field-based methods allow for a quick estimation of body composition, they may
compromise validity and reliability to some extent. Traditionally, the assessment of body composition
in the field has been by skinfold caliper. This popular technique is relatively simple, inexpensive, and
may be used in many situations. The degree to which skinfold measurements provide a valid
assessment of body composition has been investigated previously (5,18), showing correlation
coefficients as high as 0.931 when compared with HW (18). Using different statistical techniques
(4,19), more recent studies have shown less agreement between skinfold thickness (ST)
measurements and measurements made using other reference methods (2,15,28). Batterham et al.
(2) highlighted a consistent underestimation of body fat in HIV patients, with the bias being as high as
8.87 %BF with an error of 4.95 %BF. These findings were reported despite data exhibiting a strong
correlation between ST measurements and DEXA (r=0.810).
Bioelectrical Impedance Analysis (BIA) is increasingly used to assess body composition, primarily
because it is relatively cheap, quick, non-invasive, and requires limited operator training. With
advances in technology and refined prediction equations, the assessment of body composition by BIA
shows similar levels of agreement with standard reference methods and other field based techniques
(9,15,21,28). Early BIA systems suffered from technical and practical limitations with, for example, a 1
cm displacement of electrodes resulting in a 2% change in resistance (7). An important development
in BIA was the introduction of contact electrodes, which negated the need for stainless steel paste-on
electrodes. This is more convenient for subjects and reduces error in resistance measurement
(20,26).
Jebb et al. (15) evaluated the TANITA 305 body composition analyzer (Tanita Corp., Tokyo, Japan)
that uses contact electrodes. This machine demonstrates reasonable agreement (bias of +0.9% body
fat, 2 SD 10.2% body fat) with a four-compartment model, which included DEXA. A further
development is the use of 8-point contact systems that improve the association between BIA and
reference standards (21), thus allowing for segmental body composition analysis. The TANITA
BC418-MA (Tanita Corp., Tokyo, Japan) is an 8-contact electrode system capable of acquiring
segmental body composition analysis without the need for gel electrodes. It has been shown that the
76
TANITA BC418-MA provides a valid measure of body composition when compared to DEXA using
segmental analysis (21).
The aim of this investigation was to determine the validity of the TANITA BC418-MA (TAN) body
composition analyzer against HW and ST (Study 1) and then, subsequently, to determine the same-
day test-retest reliability of the TAN (Study 2).
METHODS
Subjects
Study 1: Validity of TAN to Determine Percentage Body Fat
A sample of 28 male subjects (age 24 ± 8 yrs, height 1.76 ± 0.09 m, mass 75.4 ± 14.5 kg) and 29
female (age 22 ± 6 yrs, height 1.70 ± 0.10 m, mass 67.2 ± 10.7 kg) were recruited following initial
health screening. Prior to any measurements, the subjects were informed of the nature of the tests
and were asked to adhere to a pretest protocol that which included a 12-hr fast, abstinence from
alcohol for 24 hrs, no exercise for 24 hrs, and to attend adequately hydrated. Females were assessed
between 6-10 days following menses to control for fluid overload states. Adherence to these criteria
was verbally confirmed with the subjects prior to participation. Each subject provided written informed
consent following a full explanation of the study procedures, which were approved by the University
Research Ethics Committee.
Study 2: Reliability of TAN to Measure Percentage Body Fat
The reliability of %BF measurements obtained from the TAN was examined in a separate subject
cohort. Following ethical approval, informed consent and health screening, 24 males (age 38 ± 12
yrs, height 1.79 ± 0.07 m, mass 82.80 ± 13.59 kg) and 28 females (age 45 ± 11 yrs, height 1.65 ±
0.08 m, mass 61.88 ± 10.46 kg) had their percentage body fat measured on two occasions using the
TAN.
Procedures
Study 1: Validity of TAN to Determine Percentage Body Fat
Subjects attended the laboratory on one occasion, during which they had body composition estimated
by three different methods (HW, TAN, and ST). The tests followed a counterbalanced order with the
same experimenter taking all measurements and recordings. The experimenter had previous
experience of body composition analysis, and was familiar and well-practiced with the techniques
used in this study. The subjects were required to wear a swimsuit during the tests. The following
measurements were recorded prior to body composition analysis: height (m), mass (kg), room
temperature (°C), and barometric pressure (mmHg).
Study 2: Reliability of TAN to Measure Percentage Body Fat
Subjects attended the laboratory on a single session during which percentage body fat was measured
twice. Both recordings were made within 15 min of each other. During the 15-min period, the subjects
refrained from any physical activity but were free to move around the laboratory.
Bioelectrical Impedance Analysis
Measurements using the TAN segmental body composition analyzer were recorded following a
standardized 10-min standing period to minimize acute shifts in fluid distribution (7). Subject details
were entered into the TAN, including information on clothing weight, gender, age, and height. When
prompted, subjects stepped onto the footpads and grasped the handles. Analysis took approximately
10 sec during which time the subjects remained still and relaxed. Measurements were recorded in the
standard mode.
77
Hydrostatic Weighing
HW was conducted using a 1.67 m3 immersion tank, a wire mesh cradle, and a single point Salter
Digital Balance model 2G-100. Following emersion in the hydrostatic tank, subjects removed trapped
air in their swimsuits. Subjects lay supine on a wire cradle fully submerged and were instructed to
forcefully exhale through a lightweight mouthpiece and tubing. At the end of the exhalation, mass was
recorded. This procedure was repeated until 2 measurements were within ±50 g. The Archimedes
principal was used to calculate body volume with an appropriate correction factor applied for residual
lung volume (1) and GI volume assumed to be 100 mL (16). Body density was then calculated from
the volume value (body mass/volume), and was entered into the Siri (22) equation for estimation of
percentage body fat.
Skinfold Thickness
Skinfold thickness was measured using a Harpenden Skinfold Caliper (Harpenden, England).
Measurements were taken from the chest, supra-illiac, and triceps for males, and from the abdomen,
supra-illiac, and triceps for females according to the published guidelines (1). Generalized skinfold
equations (1) were used to predict body density. %BF was estimated using the equation of Siri (22).
Statistical Analyses
Body composition data are presented as means ± SD for all subjects and by gender. The percentage
body fat measurements of the field-based methods, TAN, and ST were statistically correlated with
HW using Pearson’s correlation coefficients. After checking the data for normal distribution and
heteroscedasticity, the assessment of bias and limits of agreement for both Study 1 and Study 2 were
analyzed using paired sample t-tests and Bland-Altman plots. The interaction between gender and
mode of assessment was investigated using 2-way mixed design ANOVA. Inferential statistics were
considered significant when P<0.05.
RESULTS
Validity of TAN to Determine Body Fat Percentage: Whole Group Analysis
Mean %BF, as measured by the Tanita BIA system, was significantly different from HW (Table 1).
TAN overestimated %BF by 1.68% (t(56)= -2.762, P=0.008). %BF as measured by ST was also
significantly different from HW (t(57)= -2.692, P=0.009), overestimating by 1.49% BF. There were
strong significant correlations between TAN and HW (rp=0.81, P<0.0005) and between ST and HW (rp
= 0.80, P<0.0005).
Table 1. Measures of Percentage Body Fat by HW, ST, and TAN. Values are means ± SD. HW,
Hydrostatic Weighing; ST, Skinfold Thickness; BIA, Bioelectrical Impedance Analysis. *Significantly different
from HW.
All subjects (n=57)
HW% BF
ST% BF
TAN% BF
19.19
±
0.86
20.68
±
0
.88
*
20.87
±
1.04
*
Min
max
5.90
-
32.20
5.60
-
33.20
5.80
-
38.00
Range
26.30
27.60
32.20
Validity of TAN to Determine Body Composition in Males and Females
There were significant correlations (ranging from 0.543 to 0.821) between all methods for both males
and females. A 2-way ANOVA showed significant differences for the main effect of gender
78
(F(1,55)=52.251, P<0.0005) and for the main effect of method (F(1,55)=5.650, P=0.005). The gender by
method interaction also showed a significant difference and pre-planned t-tests indicated that for
males, ST was significantly different to HW and TAN, but TAN was not different from HW (Table 2).
In females, TAN was significantly different to both HW and ST, but there was no difference between
HW and ST (Table 3). Table 4 shows the mean bias and limits of agreement for all subjects and both
males and females. While there is a small negative bias for TAN and ST compared to HW for the
group as a whole and for men and women, the limits of agreement are large ranging from 7.11% BF
to 9.58% BF.
Table 2. Measures of Percentage Body Fat in Males.
Males(n=28)
HW
ST
TAN
15.11
±
1.01
16.72
±
1.00
*
15.04
±
0.92
Min
max
5.90
-
27.10
5.60
-
30.70
5.80
-
26.40
Range
21.20
25.10
20.60
Values are means ± SD. HW, Hydrostatic Weighing; ST, Skinfold Thickness; BIA, Bioelectrical Impedance
Analysis. *Significantly different from HW.
Table 3. Measures of Percentage Body Fat in Females.
Females (n=29)
HW
ST
TAN
23.13
±
0.91
24.5
±
0.9
2
26.5
±
1.08
*
Min
max
13.50
-
32.20
13.10
-
33.20
13.80
-
38.00
Range
18.70
20.10
24.20
Values are means ± SD. HW, Hydrostatic Weighing; ST, Skinfold Thickness; BIA, Bioelectrical Impedance
Analysis. *Significantly different from HW.
Table 4. Mean Bias and 95% Limits of Agreement for Percentage Body Fat (TAN and ST
relative to HW).
Whole Group
Male
Female
Bias
LOA
B
ias
LOA
Bias
LOA
TAN
-1.68 9.00 0.07 9.58 -3.37 7.11
ST
-
1.49
8.21
-
1.61
7.43
-
1.38
9.02
Study 2: Reliability of BIA to Measure Percentage Body Fat
The reliability of the TAN to assess body composition was investigated. A good level of reliability was
demonstrated with a test re-test coefficient of variation of 1.4%. There was no significant difference
79
between mean scores, 23.38% BF for trial 1 and 23.37% BF for trial 2. Bland and Altman analysis
gave an overall bias of 0.02% BF and 95% confidence limits of 0.91% BF (Figure 1).
Figure 1. Bland and Altman Plot. Trial 1 and Trial 2 using the Tanita BC418-MA
DISCUSSION
The accurate determination of body composition requires expensive equipment and complex and
time consuming methods (e.g., DEXA or HW) that are often beyond the scope of most clinical and
health-based practice. Thus, most clinical, health, and/or exercise physiology professionals rely upon
estimates such as body mass index or, at best, the measurement of ST to determine changes in body
fatness. Problems exist with BMI in that two individuals might have the same BMI but different body
compositions. While the determination of body composition through the measurement of ST does
alleviate this problem, subjects (particularly overweight or obese subjects) often feel self-conscious
about having these measures taken and might avoid participating in studies where the measurement
of ST is a requirement. That is why a simple non-invasive method of determining percentage body fat
would be of value to clinical and healthcare based practice as well as research. However, for these
methods to be of the greatest practical use, the measurements must be inexpensive, non-invasive,
operator friendly and, most of all, reliable (2).
BIA has been used with increasing frequency for the determination of body composition because it is
quick, inexpensive, non-invasive, and requires limited expertise. BIA initially suffered bad press due
to technical and practical limitations, although recent advances in technology and refined prediction
equations have significantly improved the technique (9,15,21,28).
This study has evaluated the validity of the TANITA BC418-MA in relation to two other accepted and
well-used methods (hydrostatic weighing and skinfold thickness) for the determination of body
-2
-1
0
1
2
510 15 20 25 30
Percentage Body Fat
Difference in % BF (Trial 1 - Trial 2)
80
composition in a cohort of 57 male and female subjects. Moreover, this study measured the same-
day reliability of the TANITA BC418-MA in a separate cohort of 52 male and female subjects. Thus,
we have added to the one study (21) that has already examined the validity of the TANITA BC418-
MA against DEXA and other studies examining the validity of earlier TANITA systems (15).
The results for the whole group showed that both TAN and ST recorded significantly different mean
%BF when compared to HW, with TAN overestimating %BF by 1.68% and ST overestimated BF by
1.49%. Other methods, for example DEXA, have shown better agreement with TAN. Pietrobelli and
colleagues (21) showed no significant mean bias when comparing body fat measured by the TAN and
DEXA. This may be because DEXA provides a more accurate measure of body composition than
hydrostatic weighing, although the absolute accuracy of DEXA has not been confirmed by chemical
analysis of cadavers. Even though no significant differences in mean %BF where reported in the
Pietrobelli et al. (21) study, there were large differences in the mean values. For example, the mean
difference between TAN and DEXA for estimation of the left arm fat percentage was 3.8% BF; 26.6 ±
12.1% for TAN compared to 30.4 ± 10.3% for DEXA. These values are larger than the differences
reported in the present study. Despite strong correlations observed between TAN and HW in our
study (r = 0.81; P<0.05), there was relatively poor agreement between %BFs from TAN and HW
(±9%, as shown in Table 2). Associations of this order have been reported elsewhere (3,21,27).
Pietrobelli et al. (21) concluded that there was no between method bias and that there were strong
correlations between the different methods of %BF assessment. However, they failed to report the
limits of agreement between methods as suggested by Bland and Altman (4).
van Marken Lichtenbelt et al. (27) validated several methods of body composition analysis, including
BIA against a 4-component model. They concluded that descriptive methods, such as ST, BIA, and
DEXA, gave typical errors ranging from 5.5% BF to 8% BF. The magnitude of the limits of agreement
observed in our study would seem to be in line with these findings and the findings of others (3). Of
importance in our study was that the agreement between ST and HW was no better (±8.21) than that
between TAN and HW. This highlights the potential for the use of BIA over the more invasive and
technically more difficult method of ST.
The group findings for male and females showed differing results. Not surprisingly, there was a
difference in body composition between the groups. However, males showed essentially no mean
bias between HW and BIA (15.11% BF vs. 15.04% BF) while females did (23.13% BF vs. 26.5% BF).
This difference, while statistically significant, equates to a clinically small difference of approximately
2%. However, this gender difference has been shown in other studies (3). Males and females
displayed similar limits of agreement, ranging from 7.11% BF to 9.58% BF. These values are similar
to previous studies (3,15,20,27), and they indicate that the TAN is associated with similar variation
relative to other methods of body composition assessment. In practical terms, the errors that occur
between differing methods of assessment may occur for a variety of reasons, including investigator
error, but may also reflect the different algorithms and prediction equations which have been
established for each method.
The second part of this investigation established the reliability of the TAN. Above all else, the
healthcare practitioner needs reliable methods of assessment, whether that is lifestyle questionnaires,
blood pressure monitors, or body composition analyzers. It should be apparent that this study has
demonstrated that the TAN is a reliable piece of equipment. Our results show no mean bias from test
to test and very acceptable limits of agreement.
81
CONCLUSIONS
The TANITA BC418MA provides the healthcare practitioner with a reliable method for assessing body
composition in both males and females and, while there are significant interactions between gender
and method of assessment, they do not represent a clinical obstacle to using this system. In addition,
coupled with its ease of use, and less invasive nature makes it suitable for assessment of body
composition in vulnerable populations such as children and the obese.
Address for correspondence: Kelly J, MSc, School of Physical and Adventure Education, University
of Chichester, Chichester, West Sussex, United Kingdom, PO19 6PE. Phone: (0044) 243-816209;
Email: j.kelly@chi.ac.uk.
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Disclaimer
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the editorial staff or the ASEP organization.
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Little remains known regarding the impact of weight loss on sarcopenic obesity (SO), and for this reason we aimed to assess the relationship between the two during a weight management program. Body composition was measured at baseline and six-month follow-up using the Tanita BC-418, and step measurements were obtained daily over a period of six months using an Omron HJ-320 pedometer, in 41 adults of both genders with obesity. The participants were then categorized according to the presence or absence of SO. After a significant weight loss, an improvement in the appendicular skeletal mass (ASM) to weight ratio (24.5 ± 3.5 vs. 26.2 ± 3.6, p < 0.01), indicated a decrease in the prevalence of SO by 12.2%. Moreover, these findings were confirmed by logistic regression analysis revealing a significant WL% ≥ 5% combined with an active lifestyle (i.e., ≥8000 steps/day), decreased the risk of SO by 91% (OR = 0.09; 95% CI: 0.02–0.56), after adjusting for age and gender. In conclusion, in a weight management setting, a personalized program for individuals with SO that incorporates new strategies in terms of weight loss and physical activity targets may be adopted to improve the sarcopenia-related index and reduce the prevalence of SO in this population.
... Несмотря на успехи в клиническом применении биоимпеданса, еще существуют некоторые проблемы, такие как интеграция устройств в системы электронного здравоохранения, поддерживающие удаленный мониторинг пользователей [1,7]. Кроме того, сложность систем биоимпеданса довольно высока (подача тока, измерение напряжения, демодуляция, обработка и т. д.), а использование высокочастотных сигналов (от десятков до сотен кГц) требует большого энергопотребления, поэтому возникают новые проблемы для оптимизации аппаратного обеспечения по размеру, энергоэффективности, надежности и точности [2,3]. ...
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Abstract. Aim. The paper aims to assess the accuracy of body composition measurement by KLU. Materials and methods. The study involved 32 subjects (males n = 11; females n = 21) aged 19–35 years (25.51 ± 5.82). The following equipment were used for the purpose of the study: height meter, TanitaBC-418 MA body composition analyser, KLU body composition tracker. Results. Significant differences in body fat (more than 20%) were found in 17 subjects. In 6 subjects, this difference was more than 40%. Therefore, in 53.12% of subjects the results obtained with different equipment did not coincide (63.63% –males; 47.61% – females). Better results were reported when measuring body water using the abovementioned equipment. There were no differences of more than 20%, while a 10%-difference was found in 15.62% of subjects. Conclusion. The difference of more than 20% reported in 53.12 % of subjects does not allow to consider KLU as an accurate device for body composition measurement or an accurate individual device. Therefore, its personal use cannot be a reliable method of body composition measurement. Keywords: body composition tracker, bioimpedance, measurement accuracy
... A constant-tension tape measure is used to obtain waist circumference, defined as the distance around the waist using the umbilicus as the reference point, and hip circumference, defined as the distance around the widest girth of the buttocks using the greater trochanter as a landmark. Body composition is also assessed via bioelectrical impedance using a validated device (Tanita 780, Arlington Heights, IL) (34). The device estimates body fat using an algorithm based on their age, sex, height, and body weight. ...
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Background Obesity is a significant contributor to breast cancer recurrence and mortality. A central mechanism by which obesity stimulates cancer progression is through chronic, low-grade inflammation in adipose tissue. Exercise interventions to target chronic inflammation has a potential to improve obesity- and breast cancer-related outcomes; however, no studies have investigated the roles of exercise in modulating adipose tissue inflammation in breast cancer survivors. Also, it is unclear which exercise prescription would be optimal to maximize the outcomes. Therefore, we designed a randomized controlled trial (Taking AIM at Breast Cancer: Targeting Adiposity and Inflammation with Movement to Improve Prognosis in Breast Cancer Survivors [AIM] Trial) to examine the mechanisms by which different modalities of exercise impact chronic inflammation as a biomarker of breast cancer prognosis. Methods The AIM trial is a prospective, three-armed, phase II randomized controlled trial investigating the effects of a 16-week supervised circuit aerobic and resistance exercise (CARE) program versus a traditional aerobic and resistance exercise (TARE) program and attention control (AC) on adipose tissue inflammation in breast cancer survivors. 276 patients who are diagnosed with stage 0-III breast cancer, post-treatment, sedentary, and centrally obese are randomized to one of the three groups. The CARE and TARE groups participate in thrice-weekly supervised exercise sessions for 16 weeks. The AC group are offered the CARE program after the intervention period. The primary endpoint is adipose tissue inflammation assessed by core biopsy and blood draw. The secondary and tertiary endpoints are sarcopenic obesity, physical fitness and function, and patient reported outcomes. The exploratory outcomes are long-term breast cancer outcomes. Discussion This is the first randomized controlled trial examining the effects of exercise on adipose tissue inflammation in obese, breast cancer survivors. Our findings are anticipated to contribute to a better understanding of exercise modalities and mechanisms on adipose tissue inflammation that can potentially improve breast cancer prognosis. Clinical Trial Registration https://clinicaltrials.gov/ct2/show/NCT03091842 identifier [NCT#03091842].
... Height was measured to the nearest 0.5 cm using a scale mounted telescopic stadiometer (Seca 220, Seca GmbH, Hamburg, Germany), with the participant's head maintained in the Frankfort Horizontal Plane. Body weight to the nearest 0.1 kg, total body fat (%), muscle mass (kg), and VAT (expressed on a range from 1 to 59) were measured by Bioelectrical Impedance Analysis (BIA) (Tanita BC-418, Tanita, Tokyo, Japan) (Kelly & Metcalfe, 2012), with participants wearing light clothing and standing on the metal contact with no shoes. Body mass index (BMI) was calculated by standard formula (weight in kg divided by squared height in m, kg/m2). ...
Article
Objective There is some controversy about the beneficial effects of occupational physical activity (OPA) on cardiovascular risk (CVR). The main aim of this study was to explore the effect of the combination of different frequencies of leisure-time physical activity (LTPA) and two types of OPA on CVR and body composition, and whether the association between physical activity (PA) and CVR was mediated by visceral adipose tissue (VAT). Methods This cross-sectional study included data from 2516 couriers living in Spain, delivering either by motorbike or foot, and practicing LTPA never, occasionally, or regularly. Couriers were classified into six categories according to LTPA and OPA; body composition was assessed by Bioelectrical Impedance, and CVR by the Framingham equation. General linear models were performed to explore the association between different categories with each outcome (CVR and body composition) and the possible role of VAT as a mediator between PA and CVR. Results Compared with the most sedentary group (motorbike couriers that never practice PA), walking couriers who practice regular PA presented the lowest CVR [β −1.58 (95% CI −2.31; −0.85)] and the lowest VAT [β −2.86 (95% CI −3.74; −1.98) followed by the motorbike couriers who practiced regular PA [β −0.51 (95% CI −1.00; −0.03) for CVR and β −2.33 (95% CI −2.91; −1.75) for VAT]. The association between PA and CVR was partially mediated by VAT. Conclusion The present results indicated that both OPA and LTPA are protective factors for CVR and play an important role on VAT accumulation.
... Body mass was measured using a bioimpedance scale (Tanita®BC-418 MA, Tanita Corp., Tokyo, Japan) previously validated with high reliability and precision (Kabiri et al., 2015). Furthermore, a strong correlation with hydrostatic weighing (r = 0.81, p < 0.001) was reported as well as an overall bias of 0.02% from test to re-test and excellent limits of agreement (Kelly & Metcalfe, 2012). The scale has a precision of 100 g, and body fat and fat-free mass were derived according to the manufacturer's formula for athletes. ...
Article
In this paper, we outline a systematic testing programme developed to help identify excellence in youth basketball players. We examine the links between biological maturation and training experience with anthropometry, body composition, physical performance, technical and tactical skills from five agecohorts, and characterize, in detail, facets of their environment. In total, 238 young basketball players aged 11–15 years, clustered into five age-cohorts (11, 12, 13, 14, 15 years) were recruited. We assessed measures across three domains: (1) biological [anthropometry, body composition, biological maturation and physical performance]; (2) skill/game proficiency [technical skills and tactical skills]; and (3) contextual [family support, coach knowledge and competence and club context]. The data were analysed using one-way ANOVAs and multivariate analysis of covariance adjusting for biological maturation and training experience. We report significant differences favouring older basketball players on most biological and skill/game proficiency variables. However, differences between age-cohorts in physical performance and technical skills were mitigated after controlling for the effects of both covariates. In conclusion, our findings highlight the important role of both biological maturation and training experience on youth basketball players’ performance and development. We discuss the implications of these findings for research as well as for athletes, parents, coaches and clubs.
... Regarding the anthropometric features, stature was measured using a Harpenden stadiometer (Holtain Ltd., Crymych, UK, precision to the nearest millimetre), arm span and hand breadth and length were assessed with an anthropometer and a sliding calliper (Siber-Hegner, GPM, Zurich, Switzerland), and body mass, body fat and fat-free mass were obtained using a Tanita BC-418 MA bioimpedance scale with a 1.4% CV [35]. Biological maturation was evaluated with a prediction equation based on age, sex, stature, sitting stature and body mass, allowing for the assessment of the peak stature velocity and timing of positive and negative maturity offset values, evidencing the years that the player is beyond or before the peak stature velocity age [36]. ...
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ue to the growing engagement of youth in water polo practice, we aimed to characterize age-grouped players across anthropometric, general and specific motor abilities and contextual domains. We have also examined the associations of players’ specific skills with their anthropometric and general motor characteristics. One-hundred-and-one male water polo players, grouped into 12-, 13- and 14-year age cohorts were recruited. One-way ANOVA explained age-cohort variance, and a multiple linear regression was used to assess the association between variables. The variance in cohorts was explained by arm span (25%), stature, hand breadth and length (17%) fat-free mass (18%), 20 m sprint (16%), sit-ups (18%), medicine ball throw (27%), anaerobic (31%) and aerobic performance (21%), change of direction (18%), and in-water vertical jump (14%). The variance of in-water vertical jump, 10 m sprint, change of direction and aerobic fitness for players’ anthropometric characteristics were, 32, 25, 14 and 10% (respectively). The players’ upper-limb explosive power explained 30, 22 and 17% of variance for in-water vertical jump, 10 m sprint and aerobic fitness, respectively. Body mass had an inverse, and arm span had a direct association with in-water vertical jump and swim velocity capability, arm span had an inverse and direct association with change of direction and aerobic fitness, respectively. The upper limbs’ explosive power related directly to in-water vertical jump and aerobic fitness skills, but inversely with 10 m sprint scores.
... In our study, women with a BF BIA % ≥35 were considered obese. The reliability study of Tanita BC418 device for use by health professionals was performed (15). Its confirmation study was conducted with dual energy X-ray absorptionmetry (DEXA), which is considered a gold standard (16). ...
... Stature was measured to the nearest millimetre using a stadiometer and weight was measured to the nearest 0.1. kg [15] using a reliable weighing scale (TANITA BC418-MA) [16]. BMI was calculated based on the International System of Units, BMI = weight (kg)/height 2 (m 2 ) and expressed as z-score in the categories NORMAL, OBESE and OVER-WEIGHT [17]. ...
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Background Low cardiorespiratory fitness (CRF) is associated with the development of cardiovascular diseases during childhood, adolescence and older ages. The purpose of the study was to investigate associations between fatness, hemodynamic characteristics and secondary time with CRF in primary school-aged children. Methods Height, weight, body mass index (BMI), blood pressure (BP), heart rate (HR), CRF (20 m shuttle-run) and sedentary time were measured for 105 children (categorized as normal, overweight, obese). The independent sample t-test checked for differences and one-way ANOVA—Post Hoc Test and stepwise linear regression analysis assessed the 20 m shuttle-run performance predictors. Results There was a statistically significant difference in CRF between boys and girls. There was a statistically significant difference between (p < 0.05) CRF for Normal weight (M = 47.58 ± 3.26 kg m⁻²) and Obese (M = 44.78 ± 3.23 kg m⁻²). CRF correlated with age, BMI and sedentary time (r > 0.3; p < 0.05). BMI is the best independent predictor of CRF. Conclusions Children with normal BMI tend to present better CRF performance than obese and overweight children. Sedentary behaviour is associated with lower CRF in primary school-aged children.
... Katılımcıların vücut ağırlığı, beden kitle indeksi, vücut yağ oranı, vücuttaki su oranı, vücuttaki kas oranı ve vücut iç yağ oranı geçerlilik ve güvenirliği Kelly ve Metcalfe (2012) tarafından yapıla Tanita-BC 418 MA marka cihazı kullanılarak ölçülmüştür. ...
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Öz Bu araştırmanın amacı, düzenli olarak B-fit spor salonlarında egzersiz uygulamalarına katılan sedanter kadın bireylerinin fiziksel uygunluklarının ve fiziksel görünümlerinin sağlanmasında B-fit egzersizlerinin etkilerini incelemektir. Araştırmaya Malatya ilinde, düzenli olarak haftada en az beş gün B-fit egzersiz uygulamalarına katılan ve diyet desteği almayan 18-35 yaş aralığında 30 sedanter kadın birey katılmıştır. Katılımcılara 8 hafta süresince düzenli olarak B-fit egzersizleri uygulanmıştır. Katılımcıların göğüs, karın, bel, kalça, uyluk, bacak ve biceps çevre ölçümleri, algı hesaplaması 0.01 cm olan gullick şeridi kullanılarak alınmıştır. Vücut ağırlığı, vücut kitle indeksi, vücut yağ oranı, vücuttaki su oranı, vücuttaki kas oranı ve vücut iç yağ oranı tanita cihazı (Tanita-BC 418 MA) kullanılarak alınmıştır. Araştırmanın ön test-son test verilerinin istatistiksel analiz değerlendirmesinde ‘’Paired Sample T-Test’’ kullanılmıştır. Elde edilen değerler ortalama±standart sapma (x̄±ss), anlamlılık düzeyi ise p<0.05 olarak kabul edilmiştir. Sedanter kadın bireylerin katılımı ile gerçekleştirilen 8 haftalık B-fit egzersiz uygulamalarının vücut ağırlığı, vücut kitle indeksi, vücut yağ oranı, vücut kas oranı, vücut iç yağ oranı; kol çevresi, göğüs çevresi, bel çevresi, karın çevresi, kalça çevresi ve uyluk çevresi ölçümleri ön test-son test değerleri arasında istatiksel olarak anlamlı farklılık olduğu belirlenirken vücut su oranı ve bacak çevresi ölçümleri ön test-son test değerleri arasında istatiksel olarak anlamlı farklılık olmadığı belirlenmiştir. Sonuç olarak, 8 hafta boyunca uygulanan B-fit egzersizlerinin sedanter kadın bireylerinin fiziksel uygunluk ve fiziksel görünümleri üzerinde birçok parametre açısından olumlu etkilerinin olduğu söylenebilir.
... Participants were given detailed information about the training program and tests, and a voluntary consent form was signed. Measurements: Measurements and Tests: The validity and reliability of the participant's body weight was measured using the Tanita-BC 418 MA brand device made by Kelly and Metcalfe (2012) 32 . The height of the participants was measured in centimeters. ...
Article
Background: Although there is a consensus among researchers that autogenic training has positive effects on the psychological state of athletes, there have not been enough studies on its effects on physical performance yet. Therefore, the effects of autogenic training on physical performance is an important question that remains to be clarified. The fact that there is no research examining the effects of autogenic training on reaction time performance constitutes the original value of the study. Aim: The aim of the study is to examine the effects of autogenic training applied during 8 weeks on the visual and auditory reaction time performances of national badminton athletes. Methods: 15 male (experimental group=8 and control group=7) national badminton player between the ages of 18-23 residing in the province of Malatya participated in the study voluntarily. In addition to the training program, autogenic training was applied to the experimental group for 8 weeks, 3 days a week, after warming up. The control group continued their regular training. In order to determine the effects of the training, the pre-test and post-test was applied to the participants. SPSS 23 Package Program was used for the analysis of the data. The data were evaluated with the Mann-Whitney U test, one of the Non-Parametric tests. The significance level was taken as p<.05. Results: The mean age of the experimental group (N=8) was 19.88±1.81, the mean height was 173.75±4.10, and the mean body weight was 68.13±5.52. The mean age of the control group (N=7) was 19.72±1.80, the mean height was 175.72±7.87, and the mean body weight was 67.58±6.61.It was observed that there was no statistically significant difference between the right and left hand visual reaction times and the right and left hand auditory reaction times of the experimental and control groups (p>.05). Conclusion: As a result, autogenic training does not have a statistically significant effect on the visual and auditory reaction time of national badminton athletes. Keywords: Autogenic training, badminton, reaction time
Article
Skeletal muscle is a clinically important body composition component which at present is difficult to quantify in vivo. Previous studies suggest that measured appendicular resistance at 50 kHz can be used to predict extremity skeletal muscle mass, although accurate technician placement of multiple gel electrodes is required. In the present study we developed a new bioimpedance analysis (BIA) electrode stand designed for rapid whole-body and segmental resistance and reactance measurements. The new system incorporates stainless steel hand and foot contact electrodes in place of gel electrodes and employes a previously reported lead placement algorithm for deriving extremity resistances without the need for placing conventional proximal limb gel electrodes. This report describes the new electrode system's design and examines the relationships between contact and gel electrode-measured resistance and between appendicular resistance measured with the recently reported lead placement algorithm and conventionally placed segmental electrodes. Results in healthy adults demonstrate high correlations between contact and gel electrodes (e.g., hand-to-hand, N = 12, r = 0.994,P < 0.001) and between segmental resistance measured by the recently reported approach and conventionally-measured segmental resistance(e.g., right arm, N = 13, r = 0.997, P < 0.001). These results strongly support the validity of the new electrode system's resistance measurements and suggests the feasibility of developing a BIA system for rapidly measuring extremity skeletal muscle mass.
Previous research has often used correlations as a statistical method to show agreement; however, this is not a valid use of the statistic. The purpose of this study was to investigate the bias and limits of agreement for three methods of estimating percentage body fat for 117 male and 114 female university athletes: hydrodensitometry (HYD), bioelectrical impedance (BIA) and skinfold calipers (SKF). The mean (SD) percentage body fat for males as assessed by HYD, BIA and SKF methods, respectively, were 13.2 (3.3)%, 14.1, (3.3)% and 13.0 (3.2)%. Female body fat measurements were 22.5 (3.9)%, 23.7 (4.3)% and 23.8 (4.2)%, respectively. Pearson product moment correlations for male and female body fat percentages between the three methods were high, ranging from 0.81 to 0.86 (P < 0.05). However, compared to the criterion measure of body fat percentage (HYD), the magnitude of agreement BIA and SKF revealed a different pattern. The mean absolute difference between HYD and BIA measurements of body fat for males was -0.8 (2.0)% fat, and between HYD and SKF was it was 0.2 (1.7)% fat. The mean absolute difference for females between HYD and BIA was -1.2 (2.5)%; for HYD and SKF it was -1.4 (2.2)%. Compared to the HYD measures for males and females, the BIA and SKF measures were as much as a 3.8% underestimation and a 6.2% overestimation of body fat. This study provides evidence that the strength of a correlation does not indicate agreement between two methods. In future, reliability and validity studies should examine the absolute differences between two variables and calculate limits of agreement around which a practitioner can appreciate the precision of the methodologies.
Article
In clinical measurement comparison of a new measurement technique with an established one is often needed to see whether they agree sufficiently for the new to replace the old. Such investigations are often analysed inappropriately, notably by using correlation coefficients. The use of correlation is misleading. An alternative approach, based on graphical techniques and simple calculations, is described, together with the relation between this analysis and the assessment of repeatability.
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All large prospective studies (n greater than 20,000) and several smaller studies have found that severe obesity [body mass index (BMI) greater than or equal to 35 kg/m2] is associated with approximately a twofold increase in total mortality and in a severalfold increase in mortality due to diabetes, cerebro-, and cardiovascular disease, and certain forms of cancer. Studies that have not been able to confirm this have been small and/or short term, have failed to control for smoking or early mortality, have controlled for intermediate risk factors in an inappropriate way, or have a reduced internal validity due to misclassification biases. As compared with BMI, abdominal obesity is a stronger predictor of mortality in most studies available. The incidence of sudden death unexplained by autopsy may be up to 40 times higher in severely obese subjects as compared with the general population. A small weight increase since the age of 18 is associated with a decreased risk whereas weight increases greater than 10 kg are associated with an increased mortality. The total mortality ratio for severe obesity decreases from 55 y of age and is not detectable above 80 y of age. Studies lacking adequate control groups indicate that a sustained weight loss may induce a reduced mortality but results from controlled intervention studies are so far not available.
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The prevalences of several risk factors and diseases are dramatically increased in obesity. In contrast, considerable inconsistencies have been reported for the relationship of obesity to the incidence of cardiovascular disease and total mortality. Suggested reasons for these inconsistencies have been confounders and surrogate risk factors, but the single most important cause is that far-reaching conclusions have been drawn from small short-term studies. Several large studies have recently proven that the incidence of cardiovascular disease is increased in obesity. Correct classification of obesity and its subgroups is also of great importance. Visceral obesity constitutes one subgroup at high risk. It seems possible to link diabetes, hypertriglyceridemia, reduced fibrinolysis, and hypertension to elevated portal free fatty acid concentrations because of an increased visceral adipose tissue depot. The quantitation of visceral adipose tissue has been improved by techniques based on computed tomography (CT) and by CT-calibrated anthropometric methods. Results from controlled intervention studies of obesity are entirely lacking but one such study has been started.
Article
The present study validates the use of dual energy X-ray absorptiometry (DEXA) for measurement of body composition. The precision error was expressed as the SD (CV%) for fat mass, FAT%, lean tissue mass, and total body bone mineral: 1.1 kg (6.4%), 1.6% (5.7%), 1.4 kg (3.1%), and 0.03 kg (1.2%), respectively. The accuracy study in vitro used (1) mixtures of water and alcohol, (2) mixtures of ox muscle and lard, and (3) dried bones. In the clinically relevant range of values there were only small influences on DEXA measurements of variations in amount and composition of the soft tissue equivalents. The accuracy study in vivo compared the components of body composition measured recently by DEXA and earlier by dual photon absorptiometry, counting of naturally occurring total body 40K, and body density by underwater weighing in 25 healthy adult subjects. We found agreement between fat percentage (and lean body mass) by DEXA and the three established measurements modalities; mean differences were (-5.3 to -0.4%) and (-0.7 to 2.5 kg) for fat percentage and lean body mass, respectively. We conclude that DEXA provides a new method of measuring body composition with precision and accuracy errors, which are compatible with the application of DEXA in group research studies and probably also in clinical measurements of the single subject.