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233
Journal of Health Science, 51(2) 233–236 (2005)
Improvement in dietary habits and regular exer-
cise is considered to be effective in preventing and/or
reducing obesity and lifestyle-related diseases. The aim
of this study was to analyze the effects of the combina-
tion of regular exercise and tea catechins intake on
energy expenditure in humans. Fourteen healthy male
subjects of 26 to 42 years of age received either a test
beverage containing tea catechins or a control bever-
age without tea catechins for 2 months period; during
this period they also engaged in treadmill exercise at a
pace of 5 km/hr for 30 min 3 times a week. Energy ex-
penditure in a sedentary condition or during the tread-
mill exercise was measured after 2 months by indirect
colorimetry. Fat utilization for energy expenditure
under both sedentary and exercising conditions was
significantly increased by the combination of regular
exercise and tea catechins intake compared to that by
exercise alone.
Key words —–— tea catechin, energy expenditure, respi-
ratory quotient, regular exercise
INTRODUCTION
Improvements in dietary habits and regular ex-
ercise are important for preventing and/or reducing
obesity or lifestyle-related diseases, and their effec-
tiveness depends on the balance between energy in-
take and expenditure.
1)
Focusing on the antiobesity effects of tea cat-
echins, we have analyzed the effects of tea catechins
intake from the viewpoint of diet therapy. Nagao et
al.
2)
demonstrated that visceral fat was reduced by
long-term intake of tea catechins in humans. We re-
ported on a murine model
3)
suggesting that tea cat-
echins could stimulate lipid metabolism in the liver
and suppress visceral fat accumulation. It is specu-
lated that tea catechins intake or regular exercise
modulates energy balance by increasing the utiliza-
tion of body fat for energy expenditure. It is antici-
pated, therefore, that tea catechins intake in combi-
nation with regular exercise may effectively stimu-
late energy metabolism and thereby suppress the
onset of obesity or lifestyle-related diseases.
The present study was performed as part of our
series of studies on the effectiveness of tea catechins,
to analyze the effects of the combination of tea cat-
echins intake and regular exercise on energy expen-
diture in humans.
MATERIALS AND METHODS
Study Subjects —–— Fourteen healthy male volun-
teers of 26 to 42 years of age were enrolled in this
study. This study adhered to the spirit of the Decla-
ration of Helsinki with adequate cautions under the
supervision of a physician. Written informed con-
sent was obtained from volunteer subjects who were
fully informed on the details and methods of this
study.
During the study period, the subjects were in-
structed not to change their daily exercise intensity
or daily diet.
Materials —–— The subjects received a beverage in
the form of a sports drink of 500 ml. As the test bev-
erages for this study, a sports drink containing 570
mg of tea catechins, and a control sports drink lack-
ing the tea catechins but containing other compounds
at the same concentrations were prepared. Both bev-
*To whom correspondence should be addressed: Health Care
Products Research Labolatories No. 1, Kao Corporation, 2–1–
3, Bunka Sumida-ku Tokyo 131–8501, Japan. Tel.: +81-3-5630-
7263; Fax: +81-3-5630-7524; E-mail: tokimitsu.ichirou@kao.
co.jp
Effects of Combination of Regular Exercise and Tea Catechins
Intake on Energy Expenditure in Humans
Noriyasu Ota,
a
Satoko Soga,
a
Akira Shimotoyodome,
a
Satoshi Haramizu,
a
Misako Inaba,
a
Takatoshi Murase,
a
and Ichiro Tokimitsu
*
,
b
a
Biological Science Laboratories, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga-gun, Tochigi 321–3497, Japan and
b
Health
Care Products Research Labolatories No. 1, Kao Corporation, 2–1–3, Bunka Sumida-ku Tokyo 131–8501, Japan
(Received November 19, 2004; Accepted December 3, 2004)
234
Vol. 51 (2005)
erages contained sweeteners (such as sugar or sugar
alcohol), acidulants (such as citric acid), electrolytes
(such as Na or K salts), antioxidants and flavor. The
pH, calorie, Na and caffeine concentrations in these
test beverages were adjusted to 3.5, 5 kcal/100 ml,
42 mg/100 ml and below 8 mg/100 ml, respectively.
The composition of the tea catechins in the test bev-
erage is shown in Table 1.
Study Design —–— The subjects were divided into
two groups (control group, n = 7; catechin group,
n = 7) so that their data of body mass index (BMI)
and indirect calorimetric profile were comparable
on a group basis. During the study period, they in-
gested 500 ml of either the catechin-containing bev-
erage or the control beverage every day for 2 months,
and engaged in a treadmill exercise at a pace of 5 km/
hr for 30 min 3 times a week. On the days of walk-
ing exercise (3 days a week), they ingested 500 ml
of either the catechin-containing beverage or the con-
trol beverage within 1 hr before or after walking.
After the 2-month intake of the test beverages, indi-
rect calorimetric analysis was performed to measure
energy expenditure under sedentary and exercising
(i.e., on the treadmill) conditions.
From 2 days before the indirect calorimetric
analysis, the subjects took specified meals for break-
fast, lunch and dinner (total calorie: 2200 kcal/day;
total fats: 55 g/day). During these 2 days, they were
not allowed to consume any alcoholic drink, and
were instructed to refrain from eating between meals.
After dinner on the day before the indirect calori-
metric analysis, intake of food or drink except wa-
ter was prohibited (13-hr fasting).
On the day of the indirect calorimetric analysis,
water intake was prohibited from 2 hr before enter-
ing the measuring room, and any physical activity
such as climbing stairs that might affect the indirect
calorimetry was also prohibited. Indirect calorim-
etry was measured in a room maintained at a con-
stant temperature and humidity of 22°C and 40%,
respectively, using the VO2000 metabolic testing
system (Medical Graphics Corporation: U.S.A.).
After entering the room, subjects became acclima-
tized in a sedentary position for 30 min, and then
ingested 500 ml of the catechin-containing test bev-
erage or the control beverage within 3 min. After
the ingestion, indirect calorimetric analysis was per-
formed in the exercising condition for 30 min while
they were walking on the treadmill at a pace of
5 km/hr, followed by another 30-min indirect calo-
rimetric analysis in a sedentary position with eyes
closed.
Statistical Analysis —–— The obtained data are rep-
resented as mean values ± standard deviations. The
significance of inter-group differences was deter-
mined by the unpaired t-test. The level of signifi-
cance was set to p < 0.05.
RESULTS AND DISCUSSION
The mean initial values of body weight and BMI
in the control and catechin groups, which were mea-
sured at the start of this study, were 68.4 ± 11.9 and
73.5 ± 7.1 kg, and 23.1 ± 3.8 and 24.5 ± 2.6 kg/m
2
,
respectively, showing no significant differences be-
tween the groups.
To obtain background data for each subject, in-
direct calorimetric analysis was performed for
30 min under sedentary and 13-hr fasting conditions
before the start of this study. In Table 2, the initial
values of energy expenditure and respiratory quo-
tient in the sedentary condition are shown. No sig-
nificant difference was observed in total energy ex-
penditure, carbohydrate and fat oxidation and respi-
ratory quotient between the control and catechin
groups.
After regular intake of the test beverages
(500 ml/day) and regular exercise on the treadmill
(3 times a week) for 2 months, indirect calorimetric
analysis was performed. Table 3 shows the evalua-
tion parameters relevant to energy expenditure in the
sedentary condition, calculated from indirect calo-
rimetric analysis data obtained during a period of
30 min after the intake of the test beverages. There
was no significant difference in total energy expen-
diture in the sedentary conditions between the con-
trol and catechin groups. However, the catechin
group showed a significantly lower carbohydrate
Table 1. Catechin Compositions of the Test Beverages
(mg/500 ml)
Control Catechin
Catechin 0.0 12.7
Epicatechin 0.0 49.7
Gallocatechin 0.0 36.0
Epigallocatechin 0.0 174.7
Catechin gallate 0.0 4.1
Epicatechin gallate 0.0 65.7
Gallocatechin gallate 0.0 9.1
Epigallocatechin gallate 0.0 218.4
Total 0.0 570.4
235
No. 2
oxidation under sedentary conditions than the con-
trol group after test beverage ingestion. On the other
hand, in the catechin group, the fat oxidation in the
sedentary condition was about 1.4-fold that of the
control group, showing a significant inter-group dif-
ference. The respiratory quotient under sedentary
conditions in the catechin group was significantly
lower than that in the control group.
Table 4 shows the data of energy expenditure
during the 30-min treadmill exercise, obtained fol-
lowing the indirect calorimetric analysis under sed-
entary conditions. No significant difference was
observed in total energy expenditure in the exercis-
ing condition between the control and catechin
groups. Also, no significant difference was observed
in carbohydrate oxidation in the exercising condi-
tion between the control and catechin groups. How-
ever, the catechin group showed a significantly
higher fat oxidation in the exercising condition than
the control group. No significant difference was
observed in respiratory exchange ratio in the exer-
cising condition between the control and catechin
groups, although the catechin group showed a
slightly lower value.
From these results, it was demonstrated that the
fat oxidation was increased in both the sedentary and
exercising conditions by tea catechin intake in com-
bination with 3-times weekly walking exercise. In
the present study, indirect calorimetric analysis was
performed under the condition of overnight fasting;
therefore, the proportion of dietary fat-derived chy-
lomicron, which is an energy source for fat utiliza-
tion, was low. Thus, it was considered that body fat-
derived lipid metabolism mainly occurred under such
conditions. It has been reported that oxidative deg-
radations of free fatty acids are increased in the liver
and muscle tissues by the increased lipolysis of adi-
pose tissues, which is a factor for increased utiliza-
tion of body fat as an energy source.
4)
We reported
that the tea catechins might contribute to an increase
in body fat utilization for energy expenditure.
5)
We
have also found that fatty acid oxidation in the liver
and skeletal muscles was increased in mice by a
combination of regular exercise and tea catechins
intake more effectively than by the exercise or tea
catechins intake alone (submitted for publication).
Table 2. Characteristics of Subjects before Test Beverage Administration
a)
Control Catechin p
b)
Energy expenditure (kcal/day) 1956 ± 563 1878 ± 426 NS
Carbohydrate oxidation (kcal/day) 299 ± 174 271 ± 185 NS
Fat oxidation (kcal/day) 1420 ± 554 1501 ± 647 NS
Respiratory quotient 0.75 ± 0.03 0.74 ± 0.05 NS
a) Means ± S.D., n = 7, b) For differences across treatments (Student’s t-test).
Table 3. Energy Expenditure, Substrate Oxidation, and Respiratory Quotient in Sedentary Subjects
a)
Control Catechin p
b)
Energy expenditure (kcal/day) 1936 ± 271 2026 ± 274 0.5473
Carbohydrate oxidation (kcal/day) 612 ± 276 334 ± 139 0.0350
Fat oxidation (kcal/day) 997 ± 240 1365 ± 273 0.0201
Respiratory quotient 0.81 ± 0.04 0.77 ± 0.02 0.0174
a) Means ± S.D., n = 7, b) For differences across treatments (Student’s t-test).
Table 4. Energy Expenditure, Substrate Oxidation, and Respiratory Exchange Ratio during the Treadmill Exercise
a)
Control Catechin p
b)
Energy expenditure (kcal/day) 7301 ± 1030 8103 ± 849 0.1072
Carbohydrate oxidation (kcal/day) 3012 ± 1062 2553 ± 1158 0.3424
Fat oxidation (kcal/day) 3956 ± 1305 5217 ± 904 0.0288
Respiratory exchange ratio 0.83 ± 0.04 0.80 ± 0.03 0.1187
a) Means ± S.D., n = 7, b) For differences across treatments (Student’s t-test).
236
Vol. 51 (2005)
Therefore, it is considered that body fat utilization
for energy expenditure may be increased in humans
as a consequence of the stimulation of lipid metabo-
lism in the liver or skeletal muscles by a combina-
tion of tea catechins intake and regular exercise at a
frequency of 3 times a week.
In conclusion, it was found that body fat utiliza-
tion for energy expenditure was more effectively
increased in both sedentary and exercising condi-
tions by the combination of tea catechins intake and
regular exercise than by the exercise alone. Thus, a
combination of regular exercise and tea catechins
intake can be expected to reduce body fat efficiently.
The obesity-improving effects of tea catechins in-
take in combination with exercise in humans remain
to be further investigated.
REFERENCES
1) NIH Technol Assess Statement Online (1992)
Methods for voluntary weight loss and control. Mar
30–Apr 1, 10, www. wellnessnet.com/bfc-NIH.htm.
2) Nagao, T., Komine, Y., Soga, S., Meguro, S., Hase,
T., Tanaka, Y., and Tokimitsu, I. Ingestion of a tea
beverage in catechins leads to a reduction in body
fat and malondialdehyde-LDL in men. Am. J. Clin.
Nutr., 81, 122–129.
3) Murase, T., Nagasawa, A., Suzuki, J., Hase, T. and
Tokimitsu, I. (2002) Beneficial effects of tea
catechins on diet-induced obesity: stimulation of
lipid catabolism in the liver. Int. J. Obes. Relat.
Metab. Disord., 26, 1459–1464.
4) Simon, W. C., Jansen, M. D. and Miles, J. M. (1994)
In vivo regulation of lipolysis in human. J. Lipid.
Res., 35, 177–193.
5) Osaki, N., Harada, U., Watanabe, H., Onizawa, K.,
Yamaguchi, T., Tokimitsu, I., Shimasaki, H. and
Itakura, H. (2001) Effect of tea catechins on energy
metabolism in rats. J. Oleo Sci., 50, 677–682.
