|
S.K. Dey and Parthasarathi
Debray
From Sports Authority of India, Netaji Subhas Eastern Center, Kolkata
700 098, India.
Correspondence to: Dr. S.K. Dey, Human Performance Laboratory, Sports
Authority of India, Netaji Subhas Eastern Center, Salt Lake City,
Kolkata 700 098, West Bengal, India.
Manuscript received: November 8, 2001, Initial review
completed: January 20, 2002,
Revision accepted: December 20, 2002.
Objective: The evaluation of physiological responses during
graded ergometry in children has been proven to be useful to determine
the growth and development of cardio-respiratory and musculo-energetic
systems and is also essential in sports and games. In India few attempts
have been made to determine the peak oxygen consumption (VO2) of
children from different regions. This study aims to investigate peak VO2
and its relation to other anthropometric parameters of school boys (8 to
14 years age) from east region (ER) and north east region (NER) of
India. Also, this stucdy attempts to find out the effect of regional
variation, including their growth and development in comparison with the
boys of other countries. Design: Boys were selected from east and
north-east states of India and then subdivided according to their age.
Subjects: The present study was carried out on 394 boys of 8 to
14 years of age, from three different states of ER and five states of
the NER on the Indian subcontinent. Methods:The habitual physical
activity, socio-cultural characteristics were assessed by standard
questionnaires. The sexual maturity status (age at puberty stage 2) was
calculated by standard indices. Height, body weight and skinfold
thickness were assessed by standard procedures. Peak oxygen uptake (peak
VO2) of boys was measured by computerized motor driven treadmill by
standard procedure. Results: The results showed that the body
size and peak VO2 of the boys from both regions increased significantly
from 8 to 14 years of age. Peak VO2 of the subjects was less than
untrained Japanese, European and American boys. The weight related and
lean body weight (LBW) related peak VO2 was also changed from 8 years to
14 years boys in both the regions. It was also observed that peak VO2
was significantly and negatively correlated with the sum of skin fold
thickness. Body size and peak VO2 were found to be significantly higher
in the ER boys than their NER counterparts at 13 and 14 years of age
only. Peak VO2 remained the same up to 12 years of age and then became
significantly higher in the ER boys at 13 and 14 years of age as
compared with their NER counterparts. Conclusions: There was a
significant difference in peak VO2 of children from ER and NER. The high
VO2 may be due to late sexual maturation and higher body size of the ER
boys at that age. The difference in body size and sexual maturation may
be due to genetic, racial, geographical, climatic and nutritional
diversity in the east )ER) and north-eash (NER) regions of India.
Key words: Body size, East & North-east India, Maximal
aerobic power, Peak VO2 .
THE highest rate
of oxygen consumption
by the body in a given period of time is considered to be the best
single index of cardio-respiratory fitness and it has therefore been
widely studied in both adults (maximum oxygen consumption, VO2
max) and children (peak oxygen
consumption, peak VO2)(1,2).
Peak VO2
of children, which indicates the aerobic energy yielding system or
aerobic power, starts to develop during the elementary school ages,
between 10-12 years, and continues to develop during puberty(2). Peak VO2
in children has been proven to be useful in determining the growth and
development of cardio-respiratory and musculoenergetic systems. It has
been shown that the absolute value of peak VO2
differes from country to country(3). But the trend of development is
almost the same. It increases with chronological age. There is no doubt,
therefore, that the VO2 max
is related to the maturity of the children at any given chronological
age. However, there exists a great deal of variation not only in peak VO2
but also in such physical dimensions as height and weight.
India is a vast country with unique cultural, social,
geographical, ethnic and climatic differences. The morphological
characteristics of Indian children vary according to regional variations
of this country. The sexual maturation also varies from one region to
another, which ultimately affects physical growth and development.
Sodhi(4) and Pathmanathan and Prakash(5) have reported that the regional
variation of morphological characteristics of Indian children occur due
to socioeconomic, climatic and genetical variations. Swaminathan et
al.(6) have worked on aerobic power and cardiopulmonary response of
exercise in healthy South Indian children and concluded that nutritional
and socio-cultural factors may play an important role in determining
peak VO 2
of children from different populations rather than ethnic differences
alone. Investigations have been made in India only regarding the
development of physical growth parameters and maximal aerobic power of
children only from east region of India(7), however, no study has been
reported on north-east Indian children, who are basically of Mongoloid
origin. This study was aimed to find out the peak VO2
values and their relation to general growth parameters of school boys
(8-14 years of age) from India’s east (ER) and north-east (NER) regions
and to investigate the effect of regional variation on the same.
Further, the study was also aimed to examine the development of maximal
aerobic power of east and north-east regions boys(8-14 years) in
comparison with the boys of other countries.
Subjects and Methods
Boys of average age of 8 to 14 years, from three
states of the east region (ER) viz., West Bengal, Bihar, Orissa and five
states of the north-east region (NER) viz., Assam, Meghalaya, Arunachal
Pradesh, Manipur and Tripura of the Indian sub-contient, were invited to
participate in a research project at Human Performance Laboratory,
Sports Authority of India, Eastern Center, Kolkata. Prior to the tests
clinical examinations by a physician were made and medically fit boys
were included in this study. The total number of selected boys was 394
from three different states of the east region and five states of the
north-east region (NER) of India. Out of 394 boys 191 boys were from ER
region and 203 boys were from NER region. The boys were subdivided
according to regions and ages. The criteria for selection of subjects
were medical fitness, age range 8-14 years and their habitual physical
activity.
The habitual physical activity and time spent in
physical education (PE) classes in school were also surveyed on the
school questionnaires and verified by interviews with boys and their
parents. Depending on the school curriculum the compulsory physical
education program varied between 1 and 3 hours per week. Those who
participated in not more than 1.5 h/wk in running, swimming, football,
cycling outside of compulsory school physical education programs were
includecd in this study.
The climate and environment of the ER states are
generally hot and humid as compared to the NER states. The ER states are
located in the plane area of the eastern part of the Indian subcontinent
with similar races, socio-economic status, cultures, food habits and
geographic and climatic conditions. The boys belonging to the states of
ER were considered as a homogenous group in respect to the factors
mentioned above. On the other hand the climatic and environmental
conditions of the NER states are generally cool and temperate as
compared to the ER states because geographically these are located
slightly above the sea level and in the mountain (Himalaya) range of
north-east part of the Indian subcontinent. NER states are largely
inhabited by dozens of tribes who are basically Mongoloid in origin with
short to medium stature and muscular body. These states have similar
races, socio-economic status, cultures, food habits and geographic,
climatic conditions. Thus, the boys of NER states were considered as a
homogenous group in respect to the factors mentioned.
Prior to initial testing all selected boys and their
parents were given a complete explanation of the purposes, procedures,
and potential risks and benefits involved in the study. They were asked
to read and sign a statement. In the case of the children, written
consent by parents or legal guardian was required in addition to the
children’s written assent. Physical characterstics of the boys and
medical tests were performed at their respective places (states) and for
peak VO 2
max they were called at the Human Performance Laboratory, Sports
Authority of India, Kolkata.
Anthropometric rod (FITKIT, USA), skinfold caliper (Harpenden,
Switzerland), steel measuring tape, weighing machine (FITKIT, USA),
sphygmomonometer, computerized treatdmill and analyzer (Oxycon Champion,
Jaeger, Germany) were procured from reliable companies. All the
instruments were calibrated before use. The instruments were available
and were in frequent use in routine testings and research.
Decimal age was computed from date of birth and date
of tests. Body weight was recorded using an electronic weighing machine
when boys were without shoes and wearing minimum clothes. Height was
measured by the anthropometric rod. Harpenden skinfold caliper was used
for skinfold measurements at the site of biceps, triceps, subscapular
and suprailliac by standard procedures(8). Body density was calculated
by using standard formula(9). The body fat percentage was calculated by
using the formula of Siri(10).
The pubertal stage was assessed according to the
indices developed by Marshal and Tanner(11) by averaging pubic hair
ratings with genetalia ratings to find out the sexual maturity status of
the boys. Based on the Marshal and Tanners’ classification, we
considered only ‘stage 2’ of pubic hair and genetalia rating. It was
calculated that of the 394 boys, 76 of the ER boys and 67 of the NER
boys were passing through ‘stage 2’. The observed mean age at pubertal
stage 2 was 12.9 ± 0.3 years in the ER boys and 12.6 ± 0.5 years in the
NER boys.
Peak oxygen uptake (peak VO 2)
or maximum aerobic power of the subjects was determined using a
continuous graded exercise test, on a motorized treadmill (LE 6000,
Erich Jaeger, Germany). All the subjects were instructed to avoid heavy
exercise and food intake at least 2 hrs before the treadmill exercise
test. The detailed procedure of the test was explained to the subjects
and the demonstration of the test was given to them. Subjects were first
familiarized with the treadmill running by allowing them to run with the
mouthpiece (with Triple ‘V’ volume Transducer, dead space less than 50
mL).
The testing protocol began with initial speed and
inclination of the treadmill being 4 km per hour and 2% respectively.
The speed was increased by 2 kmh –1
at every 2 minutes till complete exhaustion while the inclination was
kept constant. The subject was verbally encouraged to perform the
maximal limits and the test was terminated when the subject could not
maintain the pace with further increments in exercise intensity. Oxygen
uptake (VO2),
CO2
production (VCO2),
heart rate (HR) etc. were monitored in every 30 seconds.
The main criterion for the attainment of VO 2
max is a leveling off or plateau of VO2
despite an increase in exercise intensity. Only the minority of children
exhibit a true VO2
plateau(3). The appropriate term to use with children is peak VO2
that represents the highest VO2
elicited during an increase test to exhaustion(12). So, two of the three
following criteria was followed for establishment of peak VO2
as a maximal index: (a) failure of VO2 to increase more than 2.1 ml.kg–1
mm–1
despite a further increase in work load, (b) respiratory exchange ratio
(RER) greater than 1.0 and (c) maximal heart rate greater than the age
predicted maximum heart rate ±5%. Additionally the appearance of signs
of exhaustion, i.e., extreme forced ventilation, fatigue, facial
flushing, dyspnea and unsteady gait was observed as subjective criteria
of peak effort(13).
The whole experiment was performed at room
temperature varying from 23 to 25 degree centrigrade with the relative
humidity varying between 50 to 60 per cent.
The collected data were analyzed using the
Statistical Package for the Social Sciences (SPSS, version 6.0, 1993).
Mean, standard deviation (SD) and analysis of variance (ANOVA) were used
to see the significant difference among the groups and multiple groups.
The level of significance was set at p <0.05. Pearson product moment
correlation coefficients were calculated as appropriate.
Results
The physical characteristics and peak cardiopulmonary
response to treadmill exercise of boys from the ER and NER regions in
relation to age are displayed in Table I. It appears that height and
body weight increased significantly (p <0.01) from the age of 8 to 14
years in both ER and NER boys. However, no such significant changes were
observed in body fat% in both the ER and NER boys. But the peak VO 2
increased significantly (p <0.01) from the ages of 8 to 14 years in both
the ER and NER boys. Peak VO2
of the boys from both the regions were positively and significantly
correlated with age (ER, r = 0.68; NER, r = 0.61). A significant
positive correlation (p <0.01) between peak VO2
(L/min) and body size (height & weight) was noted in both the regions
(height, weight: ER r = 0.81, 0.79 and NER r = 0.75, 0.72). Peak VO2
expressed in relation to body weight showed a significant relationship
with age (p <0.05) in both the regions. The peak VO2
and also weight related peak VO2
were significantly correlated with the body fat% (peak VO2:
ER r = – 0.50, NER r = – 0.48 and weight related peak VO2;
ER r = –0.55, NER r = – 0.41). Peak VO2
related to lean body weight (LBW) also changed significantly with age (p
<0.05).
Table I– Mean, SD and Level of Significance of Physical Characteristics, Sum of Skinfolds
and Peak Cardiopulmonary Response to Treadmill Exercise of the Boys from East and North-east
Regions of India.
Age
groups
|
Age
(years)
|
No. of
subjects
(n)
|
Height
(cm)
|
Body
weight
(kg)
|
Body
fat%
|
Peak
Oxygen
Uptake
(1.min–1)
|
Peak
Oxygen
Uptake
(ml.kg–1)
|
Peak
Oxygen
Uptake
(ml.LBW–1)
|
Peak
Heart
Rate
(beats min–1)
(min–1)
|
|
|
East Region
|
8
|
8.2
|
24
|
1.32
|
26.0
|
7.8
|
1.19
|
45.76
|
49.4
|
204
|
|
(0.75)
|
|
(0.75)
|
(4.2)
|
(0.27)
|
(0.12)
|
(2.8)
|
(2.6)
|
(5)
|
9
|
9.3
|
27
|
1.37
|
28.2
|
8.0
|
1.32
|
46.80
|
50.2
|
203
|
|
(0.5)
|
|
(0.92)
|
(5.7)
|
(0.5)
|
(0.15)
|
(4.1)
|
(3.0)
|
(5)
|
10
|
10.4
|
22
|
1.40
|
31.5
|
8.4
|
1.47
|
46.66
|
50.1
|
202
|
|
(0.3)
|
|
(0.91)
|
(6.2)
|
(0.54)
|
(0.18)
|
(4.8)
|
(4.2)
|
(9)
|
11
|
11.5
|
29
|
1.46
|
33.5
|
8.6
|
1.62
|
46.35
|
52.3
|
199
|
|
(0.5)
|
|
(0.62)
|
(3.9)
|
(0.61)
|
(0.20)
|
(5.1)
|
(3.2)
|
(8)
|
12
|
12.7
|
30
|
1.49
|
36.2
|
8.8
|
1.70
|
47.22
|
51.4
|
202
|
|
(0.8)
|
|
(0.85)
|
(5.2)
|
(0.56)
|
(0.25)
|
(4.8)
|
(3.0)
|
(5)
|
13
|
13.6
|
31
|
1.55
|
40.2
|
8.9
|
1.91
|
47.51
|
52.2
|
198
|
|
(0.3)
|
|
(0.76)
|
(6.9)
|
(0.91)
|
(0.34)
|
(3.9)
|
(5.4)
|
(7)
|
14
|
14.5
|
28
|
1.64
|
45.0
|
9.0
|
2.14
|
47.55
|
52.7
|
195
|
|
(0.2)
|
|
(0.64)
|
(5.5)
|
(1.0)
|
(0.39)
|
(4.2)
|
(4.9)
|
(8)
|
Analysis
of variance
(all age group)
|
p <0.01
|
|
p <0.01
|
p <0.01
|
ns
|
p <0.01
|
p <0.05
|
p <0.05
|
ns
|
|
North-East Region |
8
|
8.5
|
31
|
1.34
|
27.2
|
8.0
|
1.20
|
44.11
|
48.2
|
208
|
|
(0.2)
|
|
(0.31)
|
(2.1)
|
(0.61)
|
(0.19)
|
(3.5)
|
(3.1)
|
(8)
|
9
|
9.5
|
28
|
1.36
|
29.1
|
8.3
|
1.33
|
45.70
|
49.9
|
208
|
|
(0.3)
|
|
(0.43)
|
(3.2)
|
(0.56)
|
(0.2)
|
(4.2)
|
(3.0)
|
(7)
|
10
|
10.7
|
27
|
1.39
|
32.5
|
8.5
|
1.45
|
44.61
|
49.2
|
205
|
|
(0.1)
|
|
(0.21)
|
(2.9)
|
(0.39)
|
(0.14)
|
(3.9)
|
(4.1)
|
(8)
|
11
|
11.2
|
32
|
1.44
|
34.8
|
9.0
|
1.61
|
46.26
|
51.2
|
200
|
|
(0.4)
|
|
(0.52)
|
(3.1)
|
(0.71)
|
(0.71)
|
(5.2)
|
(3.0)
|
(7)
|
12
|
12.6
|
27
|
1.46
|
36.0
|
9.3
|
1.68
|
46.66
|
51.5
|
199
|
|
(0.3)
|
|
(0.39)
|
(5.2)
|
(0.61)
|
(0.15)
|
(4.5)
|
(4.1)
|
(6)
|
13
|
13.4
|
28
|
1,52*
|
39.0**
|
8.8
|
1.83**
|
46.92**
|
51.4*
|
188
|
|
(0.2)
|
|
(0.61)
|
(2.8)
|
(0.56)
|
(0.43)
|
(4.8)
|
(5.7)
|
(5)
|
14
|
14.4
|
30
|
1.56*
|
43.5*
|
9.6
|
2.05*
|
47.12*
|
52.0*
|
195
|
|
(0.5)
|
|
(0.58)
|
(3.9)
|
(0.42)
|
(0.35)
|
(3.9)
|
(5.1)
|
(6)
|
Analysis
of variance
(all age groups)
|
p <0.01
|
|
p <0.01
|
p <0.01
|
ns
|
p <0.01
|
p <0.05
|
p <0.05
|
ns
|
Values are means (standard deviations), ns = not significant, * P <0.01 and **P < 0.05,
when analysis of variance were done between same age groups of two different regions.
Mean values of height and body weight were found to
be significantly higher in ER boys at 13 and 14 years of age as compared
to their NER counterparts. It is evident from the table that the peak VO 2
and weight related peak VO2
remained constant upto 12 years of age in both the regions and then the
values increased significantly in ER boys (at 13 and 14 years) as
compared to NER boys. Signficant changes were found in LBW related peak
VO2
in case of 13 and 14 years of boys (p <0.05).
Table II represents the comparative values of peak VO2
of children (boys) of the present study with their international
counterparts. By and large the present values of peak VO2
were found to be well comparable with their international counterparts.
Figures 1 and II present changes in VO2
max of ER and NER boy in respect to body weight and lean body bweight (LBW)
respectively.
TABLE II - Comparison of cross sectional
peak VO2 values of untrained boys of different countr5ies
with the present study
| Country |
Age
(Years) |
Mode** |
Peak VO2
(L/min) |
Peak VO2
(ml/kg/min) |
Country |
Age
(Years) |
Mode** |
Peak VO2
(L/min) |
Peak VO2
(ml/kg/min) |
| Sweden |
7-9 |
T |
1.75 |
56.9 |
|
13.0 |
B |
2.19 |
44.3 |
|
10-11 |
T |
2.04 |
56.1 |
|
8-9 |
T |
1.56 |
57.7 |
|
12-13 |
T |
2.46 |
56.5 |
South Africa* |
10-11 |
T |
2.01 |
56.1 |
|
14-4.5 |
T |
3.53 |
59.5 |
|
12-13 |
T |
2.35 |
59.4 |
| France* |
11 |
B |
1.74 |
49.2 |
Finland* |
12.1 |
B |
2.13 |
51.1 |
|
12 |
B |
1.77 |
47.8 |
|
14.6 |
B |
3.11 |
56.0 |
|
13 |
B |
2.10 |
47.8 |
Japan* |
10.2 |
B |
1.10 |
38.6 |
|
14 |
B |
2.34 |
43.9 |
|
11.2 |
B |
1.34 |
39.7 |
|
15 |
B |
2.68 |
48.9 |
|
12.3 |
B |
1.43 |
39.8 |
| Netherlands* |
13 |
T |
2.54 |
59.3 |
|
13.4 |
B |
2.05 |
44.5 |
|
14 |
T |
2.82 |
58.8 |
|
14.3 |
B |
2.38 |
50.5 |
| Great Britain* |
9.0 |
B |
1.38 |
48.9 |
Present study (east boys) |
8.2 |
T |
1.19 |
45.76 |
|
10.8 |
B |
1.63 |
46.2 |
|
9.3 |
T |
1.32 |
46.80 |
|
12.8 |
B |
2.05 |
49.6 |
|
10.4 |
T |
1.47 |
46.66 |
| Australia* |
11.5 |
B |
1.71 |
47.5 |
|
11.5 |
T |
1.62 |
46.35 |
|
12.6 |
B |
2.05 |
46.5 |
|
12.7 |
T |
1.70 |
47.22 |
|
13.5 |
B |
2.24 |
49.0 |
|
13.6 |
T |
1.91 |
47.51 |
|
14.5 |
B |
2.75 |
50.5 |
|
14.5 |
T |
2.14 |
47.55 |
| United States* |
10.1 |
B |
1.74 |
49.8 |
Present Study (north-east boys) |
8.5 |
T |
1.20 |
44.11 |
|
11.4 |
B |
1.97 |
45.8 |
|
9.5 |
T |
1.33 |
45.70 |
|
12.5 |
B |
1.85 |
45.9 |
|
10.7 |
T |
1.45 |
44.61 |
|
13.4 |
B |
2.51 |
48.8 |
|
11.2 |
T |
1.61 |
46.26 |
| Columbia* |
8-8.9 |
T |
1.43 |
52.0 |
|
12.6 |
T |
1.68 |
46.66 |
|
10-11.9 |
T |
1.74 |
52.5 |
|
13.4 |
T |
1.83 |
46.92 |
|
12-13.9 |
T |
2.17 |
51.8 |
|
14.4 |
T |
2.05 |
47.12 |
| Canada* |
10.0 |
B |
1.59 |
55.4 |
|
|
|
|
|
* * VO2 measured by B.
Bicycle Ergometer, T. Treadmill, * Krahenbuhl et al., 1985(3).
Fig.1.
Changes in Peak VO2 max (ml.kg-1.min-1)
of ER & NER boys with age
Fig. 2. Changes in Peak VO2 max (ml.LBW–1. min–1)
of ER & NER boys with age.
Discussion
Regardless of region, boys peak VO2
increased with age and this is in accordance with reports from other
studies(1,3,14). The peak VO2
of the ER and NER boys was found to be lower than those reported of
American, European and Japanese untrained boys(3,12,15). These
differences are, however, largely due to the difference in body size of
the subjects. The present study further reveals that the boys’ peak VO2
expressed relative to body weight slightly increased from 8 to 14 years
of age in ER and NER boys. Similar observations were also reported by
various researchers(3). The peak VO2
expressed relative to body weight of the ER and NER boys was found to be
well comparable with those of American, European and Japanese untrained
boys(3). This finding is also corroborated with the different findings
from India(6). They have also reported that the peak VO2
expressed as relative to body weight of South Indian boys was found to
be similar to those of North American boys.
Peak VO 2
of the present study was positively correlated to body size (body weight
and height) in both the ER and NER boys and the correlation was almost
similar to those as reported by various authors(16,17).
The present study revealed that the peak VO 2
was significantly higher in the ER boys at 13 and 14 years of age only.
This may be due to the larger body size of the ER boys at 13 and 14
years of age as compared to their NER counterparts. The present study
further reveals that the ER boys were late maturers as compared to their
NER counterparts (as indicated by average pubic hair ratings with
genetalia ratings). This may be due to the difference in genetic,
racial, maturational, climatic and geographical factors. However, it has
been reported that those who mature early are shorter in height that the
late maturers(18). This hypothesis was also found to be true in the
present investigation. It has also been observed that body size and
proportion varies considerably with the maturity status of an individual
(developing stage) during the adolescent period, but maturity related
variation in physique is also noted during childhood(19). Reports show
that sexual maturation varies from one region to another of India, which
ultimately affects the physical growth and development in terms of
height and body weight(20). The growth and development are influenced by
the variation of climatic condition, which is also in agreement of the
present study as the climatic conditions of the regions are
different(21).
It may be concluded from this study that body size
and peak VO2
increases from 8 years to 14 years of age in both the ER and NER boys.
The peak VO2
values are less than those of untrained American, European and Japanese
boys. But the peak VO2
expressed as relative to body weight has been found to be well
comparable with their international counterparts. The maximal aerobic
power remained the same up to 12 years of age and then was significantly
higher in the ER boys at 13 and 14 years of age as compared with their
NER counterparts. The peak VO2
related with lean body weight was also significantly higher in ER boys
in 13 and 14 years of age. The underlying factors may be due to the late
sexual maturation and greater body size of the ER boys at that age.
These differences including maturity status may be due to the diversity
in the genetic, racial, climatic, geographical and nutritional factors
in the east (ER) and north-eash (NER) regions of India.
Acknowledgement
The authors express their sincere gratitude to the
Sports Authority of India, Eastern Center, Salt Lake City, Kolkata for
providing facilities, funds and the subjects who were volunteers for the
present study. The authors are also grateful to Prof. S.P. Chatterjee,
Department of Physiology, Calcutta Univer-sity, Kolkata, Dr. S. Nag,
Department of Physiology, M.B.B. College, Tripura for their valuable
suggestions and cooperation. The authors are also thankful to D.I.C.,
Bose Institute, Kolkata for Medline searching.
Contributors: Both authors were involved in
designing, data collection, analysis and writing the paper. SKD shall
act as guarantor.
Funding: Sports Authority of India.
Competing interests: None stated.
|
Key
Messages |
|
• Peak VO2 of the boys from east and
north-east India is less than untrained Japanese, European and
American boys.
• Peak VO2 is significantly and positively
correlated with age and body size.
• Height, weight and peak VO2 at 13 & 14
years of ages are higher in boys from Eastern India as compared
to the north-east region.
|
|
1. Bar-Or O. Pediatric Sports Medicine for Prac-titioner. New
York, Springer-Verlog, 1983.
2. Astrand PO, Rodahl K. Textbook of Work
Physiology. New York, McGraw Hill, 1986.
3. Krahenbuhl GS, Skinner S, Kohart WM.
Development of maximal aerobic power in children. Exer Sports
Sci Rev 1985; 13: 503-538.
4. Sodhi HS. Sports Anthropometry: A
Kinan-thropometric Approach. Mohali, Chandigarh, Anova
Publication, 1991; pp 176-185.
5. Pathmanathan G, Prakash S. Growth of
sitting height, subischial leg length and weight in well-off
northwestern Indian children. Ann J Hum Biol 1994; 21: 325-334.
6. Swaminathan S, Vijayan VK, Venkates P,
Kuppurao KV. Aerobic capacity and cardio-pulmonary response to
exercise in healthy south Indian children. Indian Pediatr 1997;
34: 112-118.
7. Chatterjee S, Banerjee PK, Chatterjee P,
Maitra SR. Aerobic capacity of young girls. Indian J Med Res
1979; 69: 327-333.
8. Eston RG, Fu F, Fung L. Validity of
conventional anthropometric techniques for predicting body
composition in healthy chinese adults. Brit J Sports Med 1995;
29: 52-56.
9. Durnin JVGA, Womersley J. Body fat
assessed from skinfold thickness: measure-ments in 481 men and
women aged from 16 to 72 years. Br J Nutr 1974; 32: 77-97.
10. Siri WE. Body composition from fluid
spaces and density: analysis of methods. In: Brojak JA,
Ed. Technique for Measuring Body Composition. Washington:
National Academy of Science National Research Council. 1961; p
223-244.
11. Marshal WA, Tanner JM. Variations in the
pattern of pubertal changes in boys. Arch Disab Child 1970; 45:
13-23.
12. Armstrong N, Williams J, Balding J,
Gentle P, Kirby B. The peak oxygen uptake of British children
with reference to age, sex and sexual maturity. Eur J Appl
Physiol 1991; 62: 369-375.
13. Martinez LR. Haymes EM. Substrate
utilization during treadmill running in pre-pubertal girls and
women. Med Sci Sports Exer 1992; 24: 975-983.
14. Andersen KL, Seliger J, Rutenfranz J,
Skrobak-Kaczynski J. Physical performance capacity of children
in Norway, Part-IV. The rate of growth in maximal aerobic power
and the influence of improved physical education of children in
a rural community. Eur J Appl Physiol 1976; 35: 49-59.
15. Armstrong N, Welsmen J. Assessment of
aerobic fitness in children and adolescents. Exer Sports Sci Rev
1994; 22: 435-476.
16. Andersen KL, Seliger V, Rutenfranz J,
Berndt L. Physical performance capacity of children in Norway:
Heart rate and oxygen pulse in submaximal and maximal exercise:
Population parameters in rural inland community with regard to
maximal aerobic power. Eur J of Appl Physiol 1974; 35: 49-59.
17. Spurr GB, Reina JC, Barac-Nieto M,
Maksudm MG. maximal oxygen consumption of nutritionally normal
white, mestizo and black columbian boys 6-16 years of age. Hum
Biol 1982; 54: 553-574.
18. Bayley N, Pinneau SR. Tables for
predicting adult height from skeletal age: revised for use with
Gruelich Pyle hand standards. J Pediatr 1952; 40: 423-441.
19. Hebbelink M, Borms J. Korperliches
wachstum and leistungsfahigkeit bei schulkindern Leipzing.
Johann Ambrosius Barth, 1978.
20. ICMR. Growth and Physical Development of
Indian Infants and Children. Ansari Nagar, New Delhi, Indian
Council of Medical Research, Technical Report Series No 18,
1989.
21. Tanner J M. Growth Assessment in Childhood and
Adolescence. In: Brooks CGD, Ed. Human Biology, Oxford,
Blackwell Scientific Publication, 1982; 9-51, 1: pp 223-244.
|
