LIGHT RESISTANCE EXERCISE THERAPY WITHOUT FOOD RISTRICTION
INCREASES ENERGY METABOLISM AND REDUCES
BODY FAT
IN
MILDLY OBESE WOMEN
Tatsuhiro
MATSUO
Abstract
The effects of light resistance exercise on resting metabolic rate (RMR), diet-induced thermogenesis (DIT) and body composition were studied in twenty mildly obese women aged 19-20 years The subjects were randomly assigned to one of the following two groups: a light resistance-training group(
n
= l o ) , and no-exercise control group (n
= l o ) In the training group, subjects performed resistance exercises with pairs of 2 kg dumb- bells everyday after supper for about 20 min All subjects were seen individually each week for nutritional counseling, with the emphasis on behavior modification that included recording daily food intake Subjects underwent several measurements(body composition, RMR and DIT test) before starting the experiment and after 12 weeks During the 12-week experimental period, body weight and body fat decreased significantly in the training group without reducing fat free mass (FFM) The training group significantly increased RMR and DIT, adjusted for body weight Changes in metabolic parameters and body composition were negligible in the control group These results suggest that light resistance exercise decreases body weight and body fat without reducing FFM in relation to increasing RMR and DITKey words
:
resistance exercise, resting metabolic rate, diet-induced thermogenesis, fat free mass, young womenIntroduction
Obesity is a major health problem in advanced nations
"'
It is associated with a significant increase in hypertention, diabetes, coronary artery disease, and mortality from certain types of cancer ' 1 3 ' It is important in developingsuccessful obesity treatment programs to define parameters that affect long-term treatment success For example, there is no agreement about the optimum diet therapy for maximizing loss of body weight and body fat and for long- term maintenance of weight reduction
Regular physical activity is widely promoted as beneficial for improving health and controlling body weight The American College of Sports Medicine advises adults to engage in aerobic exercise for 20 to 60 minutes,
3
to5
days per week'"' Aerobic exercises such as jogging, cycling, or swimming, are generally recommended ('' because they result in greater utilization of fat stores and greater energy expenditure in a typical training session than does anaerobic training 'b' However, studies of aerobic exercise have shown equivocal results Some investigators report reductions in FFM " while others report no loss ofFFM beyond that caused by dieting without aerobic
exercise '942' Furthermore, it is difficult for many obese persons to develop the habit of aerobic exercise training because of mental stress or orthopedic lesions
Some recommend that, in addition to aerobic exercise, resistance exercise be included in adult fitness programs '4'
Resistance exercise is important in the development and maintenance of fat free mass (FFM) and in improving or maintaining muscular strength 'I3 14' Resistance exercise is also reported to have additional benefits, such as injury prevention, weight control, prevention of osteoporosis, and improvement of cardiovascular risk factors 'I5 16'
In theory, resistance exercise should be beneficial for weight control, because when FFM increases, resting metabolic rate (RMR)
,
and therefore energy requirements, should also increase "" However, the extent to which resistance exercise is able to increase RMR has not been documented Broeder et a1 "" compared the effect ofresistance and aerobic exercises on body composition and RMR in healthy, nondieting young men Resistance exercise was associated with increased strength and FFM, but body weight and RMR did not change significantly Aerobic exercise was not associated with a significant change in either FFM or RMR Women typically have
50 Tech Bull Fac Agr Kagawa Univ , Vo152, 2000
higher body fat and lower FFM and RMR than men Resistance exercise increased FFM in young 'I8' and older 'Ig'
women However, the effect of resistance exercise on RMR in women is not clear The purpose of this study was to examine the effect of light resistance exercise on RMR, diet-induced thermogenesis (DIT) and body composition in mildly obese young women
Methods
1 . Subjects
Twenty young Japanese women, aged 19-20 years, who did not have a habit of daily exercise were recruited to participate in this study All procedures were in accordance with the Helsinki Declaration of 1975, as revised in 1983 After a detailed explanation of this study, each subject gave her informed written consent. Except for obesity, the subjects were determined to be free of disease by a medical examination before the study No subjects were using illegal drugs or taking medications that affect body weight The day in the menstrual cycle at the beginning and end of the study was noted because fluctuations in metabolic parameters can occux during the cycle "O'
Subjects started the exercise program immediately after pre- metabolic tests Because the study period was 12 weeks, most of the women were at about the same point of their cycle (mid-follicular phase) when RMR, DIT and body composition were remeasured as they were at the beginning
The subjects were randomly assigned to one of the following two groups: light resistance training group (
n
= l o ) , and no-exercise control group (n
= l o ) The base line characteristics of the subjects in both group are shown in Table 12 . Resistance exercise
The subjects in both groups performed light resistance
Table 1 Initial physical characteristics of the subjects Variable Training group ( n Control group
=lo) ( n =lo) Age (y) 1 9 6 t 0 5 2 0 3 f 0 6 Height (m) 161t-008 1 5 9 3 ~ 0 08 Weight (kg) 61 1 + 5 3 60 8 f 6 2 Body fat (%) 3 0 9 + 3 6 29 8 + 4 1 (kg) 1 8 9 + 2 9 1 8 1 f 3 2 Fat free mass (kg) 42.2 t 3 6 4 2 7 f 4 O Values are means
+
standard deviationexercises with pairs of 2 kg dumbbells everyday after supper A warm-up of
5
min of stretching preceded the dumbbell exercise The resistance exercise consisted of 12 movements used to exercise the large muscle groups of the upper and lower body The exercises were standing shoulder press, bent dumbbell row, squat, upper body twist, butterfly, bent lateral raise, simultaneous curl, concentration curl, one hand draw up, kickback, front dumbbell raise, and arm extension "' 23' The resistance exercises targeted the chest, shoulders, biceps, triceps, back, thighs and abdominals Subjects performed 15 repetitions of each exercise, with 30 sec of rest between the different exercises Subjects grasped the dumbbell bars firmly, then ~aised and lowered the weights slowly in a continuous motion If subjects grew fatigued during the exercise, they performed a stretching exercise until they recovered their strength Total exercise time each day was about 20 min3 . Diet
The subjects received normal Japanese food ad lzbitum Food consumption by the subjects is shown in Table 2
Subjects were seen individually each week for nutritional counseling, with emphasis on behavior modification that included recording daily food intake Behavior modifica- tion has been shown to improve long-term weight loss programsz4 25' Subjects were asked to record and maintain
their usual sedentary activity pattern during the study except for the exercise prescribed Body compositions (body weight and percentage of body fat) were measured
Table 2 Mean energy consumption of subjects per week Training group
Variable Control group
( n =lo) ( n =lo) week M Jlday 1 7 7OfO 70 7 38t-0 61 2 7 49+0 52 7 46+0 69 3 7 4 5 t 0 7 5 7 2 1 f 0 6 9 4 7 32fO 72 5 698f 0 5 7 6 7 26+0 92 7 7 3 3 r t l 0 7 8 6 9 1 2 1 44 9 702+102 10 7 3 1 3 ~ 0 9 0 11 7 09+0 89 12 7 36t-0 92
weekly to observ the development of the experiment
4 . Measurement procedures
Subjects underwent several measurements before starting the experiment and after 12 weeks while still dieting Measurements at the end were conducted >24 h after the previous exercise session Subjects were requested to fast for 12 h beforehand and void bowels and bladder in the morning The technicians performing the procedures were blind to the subjects' group assignments The procedures were performed in the following order: RMR, DIT, and body composition All procedures were performed in a laboratory under the uniform conditions (temperature: 22+
1 "C, humidity: 60%)
5
.
RMR and DIT testsThe DIT test meal consisted of bread and butter, boiled egg, bone less ham, orange juice, apple, and yogurt It provided energy as carbohydrate (58%), fat (24%) and protein (18%) The energy of the test meal was 2 53 MJ RMR and DIT tests were determined at 10:OO-13:45 h after the subject rested comfortably for 45 min, in a supine position, while trying not to move or fall asleep The subjects were fed a test meal at 10:30-10:45 h The subjects then rested for 3 h (10:45-13:45 h) During rest, oxygen uptake and respiratory quotient (RQ) were mea- sured Blood samples were collected from the cephalic vein at the level of the forearm to obtain serum and plasma at 10:30, 11:00, 11:30, 12:00, 12:30, and 13:30 h
6 . Measurements
Indirect calorimetry was performed by the ventilated hood technique. For measurement of oxygen uptake and RQ, the subjects wore face masks ( ~ a k e i Co., Ltd., ~ o k y o ) continuously for 225 min, except for meal time (15 min).. All expired gas was collected into a Douglas bag ( ~ a k e i Co., Ltd
,
~ o k y o ) , and the bag was changed every 15 min during rest. The concentrations of' oxygen and carbon dioxide in the expired gas were immediately analyzed by a gas analyzer (Model RAS-30, RAS-40, AIC C o , Ltd.., 'Tokyo) E,nergy expenditure was calculated from oxygen consumption and carbon dioxide production, corrected for urinary nitrogen loss as described by ~errannini'~~'. The RQ was also calculated and used as an index of' carbohydrate and fat utilization. Energy expenditure of DIT was determined by the formula: postmeal total energy expendi-ture (PTEE~~~,,,) - RMR180mm
Plasma glucose was assayed by a glucose analyzer with electrochemical detection (Model GA-1140, Kyoto Daiichi Co
,
Ltd, ~ ~ o t o ) and a kit (GLC-C) purchased from Kokusai Shiyoku Co,
Ltd,
Kobe Serum triacylglycerol (TG) and free fatty acids (FFA) were determined enzymatically with kits (TG-A, NEFA-~5) purchased from Kokusai Shiyoku Co,
Ltd, Kobe and Nippon Shoji C o , Ltd , Osaka, respectively Serum immunoreactive insulin was determined by radio-immunoassay (two-antibody system) with kits (~nsulin 'Eiken') purchased fiom Eiken Chemical Co,
Ltd,
Tokyo The 3-hr area under the curve for glucose, insulin, TG and FFA was calculated by time integration using a personal computer (Macintosh LC 575, Apple Japan, Inc )7 . Body composition
The subjects' height and weight were measured by conventional methods Percentage of body fat, fat mass and FFM were determined by bioelectrical impedance analyzer
(Model TBF-102, Tanita Co
,
Ltd., ~ o k y o )8
.
Statistical analysisStatistical analysis was conducted using a personal computer (Macintosh LC 575, Apple Japan, Inc ) with a statistical package program (Stat View 4 02, Abacus Con- cepts, Inc, Berkeley, CA) Data were analyzed by the Student's unpaired t-test to show differences in variables between groups Changes in variables within groups fiom baseline to 12 weeks were compared using Student's paired t-tests
Results
1
.
Body weight and body compositionMean body weight and body fat weight were signifi- cantly reduced (p<O 05), whereas the change in FFM was negligible in the training group (Fig 1) Body mass index (BMI) and percent body fat were also reduced (23 6 f 2 7 to 2 2 9 f 2 4 kg/m2 (p<005) and 3 0 9 f 3 6 to 2 8 2 f 3 3 % (p<O 05)) No significant differences in body weight and body fat weight were observed in the control group(Fig 1)
2 . RMR and DIT
Oxygen uptake before and after the test meal ingestion was measured for
3
h to assess the RMR and DIT The52 Tech Bull Fac Agr Kagawa Univ , Vo152, 2000
Fig
u
Training Control
1 Changes in body weight, body fat weight and fat free mass in the training and control groups Before and
.
after experiment Values are means and standard deviation *Statistically significant differences from baseline (p<O 05, Student's paired t-test)average values for oxygen uptake are shown in Fig 2 . RMR and DIT adjusted for body weight increased significantly in the resistance-trained group (p<0.05), whereas no significant differences in RMR and DIT were observed in the control group (Fig. 3) .. On the other hand, the change in basal and postprandial RQ were negligible in both groups for the 12-week experimental period (Fig. 2)
3 . Plasma glucose, serum insulin, TG, and FFA Fasting plasma glucose concentration and 3-hr glucose area (calculated from glucose concentration
--
time curve) significantly decreased in the training (p<0.05), but not inBefore After
+
+- Training + + Control[
Meal 0 7 0 L ' n ' ' ' " ' ' ' ' ' 1 -30 0 30 60 90 120 150 180Time after ingestion (min)
Fig 2 Oxygen uptake (top) and respiratory quotient (RQ, bottom) at rest and after meal ingestion before and after 12-week experimental period The RQ was calculatred from oxygen uptake and carbon dioxide production Each point represents the mean value for ten subjects.
the control group for the 12-week experimental period ( ~ i g 4) Fasting and 3-hr area of serum insulin did not in either group for the 12-week experimental period (Fig 4). Fast- ing serum TG concentration and 3-hr TG area significantly decreased in the training group (p<O 05), but not in the control group for the 12-week experimental period (Fig
5)
Fasting and 3-hr area of serum free fatty acids did not change in either group for the 12-week experimental period( ~ i g 5)
Discussion
The results show that light resistance exercise for 12 weeks without energy restriction significantly decreased body weight and body fat without reducing FFM. The decreases in body weight, percent body fat, body fat
Training
Control
Fig
3
Changes in resting metabolic rate and diet-induced thermogenesis in the training and control groups Before and.
after experiment Values are means and standard deviation *Statistically significant differences from baseline (p<0 05, Student's paired t-test)weight and BMI were not shown in the control group These results support our previous findings '"I 22'
The subjects in the training program were young women who reported moderate levels of aerobic activity estimated by V02,,, tests before the study Mean BMI was within the range 2 0 0 to 24
9
associated with the lowest health risks "" However, the mean percent body fat for thesubjects in the training group was above the desirable range (30%) for women aged 20 years before the study '2' Thus, on average, although these women were not overweight, could be considered overfat.
Subjects did not appear to alter dietary intake in response to resistance exercise during the 12-week experimental period However; there was a favorable change in body composition. After 12 weeks, the subjects in the training group maintained FFM and lost body fat such that the mean percent body fat of' this group was
within the recommended rage. Thus, favorable body composition was obtained using a light-intensity resistance exercise without imposing an energy restriction
Cullinen et a1
'"'
reported that a moderate-intensity resistance training program increased strength and FFM, and decreased body fat during a 12-week experimental period The disagreement between their study and ours concerning the effects of resistance exercise on FFM may be due to the quality and quantity of training during the experimental period The resistance-exercise program of Cullinen et a1 lasted approximately45
minutes'*'
How- ever, it is difficult for many obese, non-trained persons to develop the habit of extended (aerobic or resistance) exercise training because of mental stress or orthopedic lesions Our resistance exercise program was much easier to instill as a habit compared with aerobic exercise or heavy resistance exercise The light resistance exercise in this study is safe, and anyone can do it any time and any placeNo clear method for resistance exercise training while dieting has been established Because a fixed light weight (2-5 kg) was used for the present study, little or no weight gain by muscle hypertrophy was produced However, light resistance exercise does stimulate protein turnover and energy metabolism 25 29 30' We recently reported that iron binding proteins in serum were increased with 12 weeks of light resistance exercise 'jO' Our present
findings demonstrate that light exercise significantly increased
R M R
and DIT without energy restriction Since it has been reported thatR M R
and DIT are mediated by the sympathetic nervous system (SNS), '3133' the effects of light resistance exercise on energy metabolism may be related to SNS activity It has been suggested elsewhere that light exercises increase SNS activity in rats '34' and humans '35'Glucose and TG disposition from blood after test meal ingestion were significantly increased with resistance exercise without altering serum insulin (fasting and 3-hr
area) These findings suggest that insulin sensitivity to glucose and lipoprotein lipase (LPL) activy in peripheral tissues, especially heart or skeletal muscle, are increased by resistance exercise The site of physiological action by LPL is the luminal surface of capillary endothelial cells where the enzyme hydrolyses the triacylglycerol compo- nent of circulating lipoprotein particles, chylomicrons, and very low density lipoproteins
'"'
On the other hand,Tech Bull Fac Agr Kagawa Univ , Vo152, 2000
Before
3-hr glucose area 3-hr
insulin
arear r
Fasting glucose Fasting insulin After
.,
Training Control Training Control
100 80
E
6 0 - 0c
4 0 - 20Fig 4 Changes in plasma glucose and serum insulin (fasting and 3-hr area) in the training and control groups Before and after experiment Values are means and standard deviation *Statistically significant differences from baseline (p<O
05,
Student's paired t-test)-
-
o - -
Fasting triacylglycerol Fasting free fatty acids Before
120
r
600r
After3-hr triacylglycerol area 3-hr free fatty acids area
25 r
-
50 r 100-
80 E 0z
s o -
.
E'
40; 20 0-
Training Control " Training Control
Fig.5 Changes in serum triacylglycerol and free fatty acids (fasting and 3-hr area) in the training and control groups Before and
.
after experiment. Values are means and standard deviation *Statistically significant differences from baseline (p<O .05, Student's paired t-test)- 500 - 400 5 300 r 200 - 100
-
0 - - - - - -resistance exercise without energy restriction did not alter basal and postprandial RQ levels, indicating that the fat oxydation rate did not change In this context, it should be noted that the fasting and 3-hr area of serum FFA were not altered by 12-weeks of resistance exercise
In our present study, the subjects performed resistance exercises every day after supper It is recognized that exercise timing is important to fat utilization, glycogen synthesis, and muscle reproduction '3' j8' Exercise after
meals burns chylomicron-triacylglycerol from dietary fat more than exercise before meals
"''
Moreover, exercise after supper is best for maintaining muscle protein because muscle protein synthesis is higher during sleep '39'In conclusion, the present study suggests that light resistance exercise decreases body weight and body fat without reducing FFM in mildly obese young women in relation to increasing RMR and DIT
References
National Institute of Health National Institute of HealthConsensus Development Panel on the Health Implications of' Obesity: National Institute of' Health Consensus Development Conference Statement Ann Int Med., 103, 1073-1077, (1985)
HUBERT, H B , FEINLEIB, M , MCNAMARA, P M , and CASTELLI, W P : Obesity as an independent risk factor for cardiovascular disease: a 26 year follow-up of participants in the Framingham Heart Study Circulation, 67, 968-977,
(1983)
VAN ITALLIE, T B : Health implications for overweight and obesity in the United States. Ann Int Med., 103, 893-998,
(1985)
American Collcge of Soprts Medicine : Position stand: the recommended quantity and quality of exercise for developing and maintaining cardiorespiratory and muscular fitness in healthy adults Med Sci Sports Exerc , 22, 265-274, (1990) GELIEBTER, A : Exercise and obesity In B Wolman (ed ), Psychological aspects of obesity: handbook pp 291-310 Van Nostrand Reinhold Company, New York (1982)
WALBERG, J L : Aerobic exercise and resistance weight training during weight reduction Sports Med, 47, 343-356,
(1989)
HILL, .J 0 , SPARLING, P B , SHIELDS, T W , and HELLER, PA :
Effects of exercise and food restriction on body composition and metabolic rate in obese women Am J Clin Nutr , 46, 622-630, (1987)
PAVLOU, K N , STEFFEE, W P , LERMAN, R H , and BURROWS, B A : Effects of dieting and exercise on lean body mass, oxygen uptake, and strength Med Sci Sports Exerc , 17, 466- 471, (1985)
BOGARDUS, C , RAVUSSIN, E., and ROBBINS, D C : Effects of physical training and diet therapy on carbohydrate metabo- lism in patients with glucose intolerance and non-insulin dependent diabetes mellitus Diabetes, 33, 31 1-318, (1984) BUSKIRK, E.R., THOMPSON, R H , LUTWAK, L., and WHEDON, G D : Energy balance of obese patients during weight reduction: influence of' diet restriction and exercise Ann NY
Acad Sci , 1 10, 918-940, (1963)
00 HAMMER, R L , BARRIER, C A , ROUNDY, E S , BRADFORD,
J M , and FISHER, A G : Calorie-restricted low-fat diet and exercise in obese women Am J Clln Nutr, 49, 77-85,
(1989)
42) NIEMAN, D C , HAIG, J L , DEGULA, E D , DIZON, G P , and REGISTER, U D : Reducing diet and exercise training effects on resting metabolic rates in mild obese women J Sports
Med , 28, 79-88, (1988)
43) EVANS, W J Reversing sarcopenia: how weight training can build strength and vitality Geriatr~cs, 51, 46-47, (1996)
04) STONE, M H , FLECK, S J , TRIPLETT, N T , and KRAEMER, W J
.
Health-and- performance-related potentional of resis- tance training Sports Med, 11, 210-231, (1991)65) DINUBILE, N A Strength training : CIIn Sports Med , 10, 33- 62, (1996)
06) VERRILL, D E and RIBISL, P M : Resistive exercise training in cardiac rehabilitation An update Sports Med , 21, 347-383,
(1976)
(17) BROEDER, C E , BURRHUS, K A , SVANEVIK, S L , and WILMORE, J H The effects of either high-intensity resistance or endurance training on resting metabolic rate Am J Clin
Nutr , 55, 802-810, (1992)
08) WILMORE, J H : Alterations in strenght, body composition and anthropometric measurements consequent to a 10-week weight training program Med Scl Sports Exerc , 6, 133-138,
(1974)
09) NICHOLS, J F , OMIZO, D K , PETERSON, K K , and NELSON, K P : Efficacy of heavy-resistance training for active women over sixty: muscular strength, body composition and program adherence J Am Geriatr Soc , 41, 205-210, (1993) (20) BISDEE, J T , JAMES, W P T , and SHAW, M A : Changes in
energy expenditure during the menstrual cycle I Nutr , 61, 187-199, (1989)
(20 MATSUO, 1, and SUZUKI, M : Effects of dumbbell exercise with and without energy restriction on resting metabolic rate, diet-induced thermogenesis, and body composition in mildly obese women Asla PacGc I Clin Nutr, 8, 136-141, (1999)
(22) MATSUO, T , and SUZUKI, M : The effect of low calorie diet therapy with and without dumbbell exercise on body rat
Tech Bull Fac Agr Kagawa Univ , Vo152, 2000
reduction in obese young women 7 Clzn Biochem Nutr , 25, 49-62, (1998)
(23) VEDRAL, M S and VEDRAL, J L : The college dorm workout pp 69-134 Warner Books, A Time Warner Company, New York (1994)
@4) RYTTIG, K R , FLATEN, H , and ROSSNER, S : Long-term eMects of a very low calorie diet (~utrilett) in obesity treatment A prospective, randomized, comparision between VLCD and a hypocaloric diet+behavior modification and their combination Int 7 Obes , 21, 574-579, (1997)
$9
WADDEN, T A and STUNKARD, A J : Controlled trial of very- low-calorie diet, and behavior therapy and their combination in the treatment of obesity J Consult Clin Psychol, 54, 482- 488, (1986)(26) FERRANNINI, E : The theoretical bases of indirect calorimetry: a review Metabolism, 37, 287-301, (1988)
(27) ATKINSON, R : Proposed standards for judging the success of the treatment of obesity Ann Intern M e d , 119, 677-680,
(1993)
(28) CULLINEN, K , and CALDWELL, M : Weight training increased fat-free mass and strength in untrained ypung women J Am
Diet Assoc , 98, 414-418, (1989)
$9) BALLOR, D L , K ~ T C H , V L , BECQUE, M D , and MARKS, C R : Resistance weight training during caloric restriction enhances lean body weight maintenance Am 7 Clin Nutr ,
47, 19-25, (1988)
(30) MATSUO, T , and SUZUKI, M : Dumbbell exercise improved iron deficient stores in young women without iron supple- mentation FASEB 7 12, A847, (1998)
(30 LANSBERG, L , SAVILLE, M E , and YOUNG, J B : Sympathoad- renal system and reglation of thermogenesis Am J Physlol,
247, E181-189, (1984)
MATSUO, T, SHIMOMURA, Y, SAITOH, S , TOKUYAMA, K , TAKEUCHI, H , and SUZUKI, M : Sympathetic activity is lower in rats fed a beef tallow diet than in rats fed a saMower oil diet Metabolism, 44, 934-939, (1995)
YOUNG, J B , SAVILLE, M E , and ROTHWELL, N J : Effect of diet and cold exposure on norepinephrine turnover in brown adipose tissue of rats J Clin Invest, 69, 1061-1071, (1982) MAZZEO, R S , and GRANTHAM, P A : Sympathetic response to exercise in various tissues with advancing age 7 Appl Physiol , 66, 1506-1508, (1989)
ESENHOFERI, G , MEREDITH, I T , and FERRIER, C : Increased plasma dihydroxyphenylalanine during sympathetic activation in humans is related to increased norepinephrine turnover J
Lab Clzn M e d , 117, 266-273, (1991)
BRAUN, J E , and SEVERSON, D L : Regulation synthesis, processing and translocation of lipoprotein lipase Blochem 7 , 284, 337-347, (1992)
M ~ r s u o , T , SUMIDA, H , JIMBO, H , SHIRAISHI, Y, TAKASHINA, S , and SUZUKI, M : Effects of dietary compo- sition and exercise timing on energy expenditure and substrate utilization in healthy young women J Clln Biochem Nutr , 20, 161-172, (1996)
OKAMURA, K , DOI, T , HAMADA, K , SAKURAI, M , MATSUMOTO, K , IMAIZUMI, K , YOSHIOKA, Y, SHIMIZU, S and SUZUKI, M : Effects of amino acid and glucose admini- stration during postexercise recovery on protein kinetics in dogs Am J Physzol , 272, E 1023-E1030, (1997)
MILLWARD, D 1 , BOWTELL, J L , PACY, P , and RENNIE, M J :
Physical activity, protein metabolism and protein require- ments Proc Nutx Soc , 53, 223-240, (1994)
