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Effects of Resistance vs. Aerobic Training Combined With an 800 Calorie Liquid Diet on Lean Body Mass and Resting Metabolic Rate

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Utilization of very-low-calorie diets (VLCD) for weight loss results in loss of lean body weight (LBW) and a decrease in resting metabolic rate (RMR). The addition of aerobic exercise does not prevent this. The purpose of this study was to examine the effect of intensive, high volume resistance training combined with a VLCD on these parameters. Twenty subjects (17 women, three men), mean age 38 years, were randomly assigned to either standard treatment control plus diet (C+D), n = 10, or resistance exercise plus diet (R+D), n = 10. Both groups consumed 800 kcal/day liquid formula diets for 12 weeks. The C+D group exercised 1 hour four times/week by walking, biking or stair climbing. The R+D group performed resistance training 3 days/week at 10 stations increasing from two sets of 8 to 15 repetitions to four sets of 8 to 15 repetitions by 12 weeks. Groups were similar at baseline with respect to weight, body composition, aerobic capacity, and resting metabolic rate. Maximum oxygen consumption (Max VO2) increased significantly (p<0.05) but equally in both groups. Body weight decreased significantly more (p<0.01) in C+D than R+D. The C+D group lost a significant (p<0.05) amount of LBW (51 to 47 kg). No decrease in LBW was observed in R+D. In addition, R+D had an increase (p<0.05) in RMR O2 ml/kg/min (2.6 to 3.1). The 24 hour RMR decreased (p<0.05) in the C+D group. The addition of an intensive, high volume resistance training program resulted in preservation of LBW and RMR during weight loss with a VLCD.
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Original Paper
Effects of Resistance vs. Aerobic Training Combined
With an 800 Calorie Liquid Diet on Lean Body Mass and
Resting Metabolic Rate
Randy W. Bryner, EdD, Irma H. Ullrich, MD FACN, Janine Sauers, MS, David Donley, MS, Guyton Hornsby, PhD,
Maria Kolar, MD, and Rachel Yeater, PhD
Department of Human Performance and Applied Exercise Science (R.W.B., J.S., D.D., G.H., R.Y.), and Department of Medicine,
School of Medicine (I.H.U., M.K.), West Virginia University, Morgantown, West Virginia
Key words: resistance training, weight loss, resting metabolic rate, very-low-calorie diet, diet
Objective: Utilization of very-low-calorie diets (VLCD) for weight loss results in loss of lean body weight
(LBW) and a decrease in resting metabolic rate (RMR). The addition of aerobic exercise does not prevent this.
The purpose of this study was to examine the effect of intensive, high volume resistance training combined with
a VLCD on these parameters.
Methods: Twenty subjects (17 women, three men), mean age 38 years, were randomly assigned to either
standard treatment control plus diet (C1D), n510, or resistance exercise plus diet (R1D), n510. Both groups
consumed 800 kcal/day liquid formula diets for 12 weeks. The C1D group exercised 1 hour four times/week
by walking, biking or stair climbing. The R1D group performed resistance training 3 days/week at 10 stations
increasing from two sets of 8 to 15 repetitions to four sets of 8 to 15 repetitions by 12 weeks. Groups were similar
at baseline with respect to weight, body composition, aerobic capacity, and resting metabolic rate.
Results: Maximum oxygen consumption (Max VO
2
) increased significantly (p,0.05) but equally in both
groups. Body weight decreased significantly more (p,0.01) in C1D than R1D. The C1D group lost a
significant (p,0.05) amount of LBW (51 to 47 kg). No decrease in LBW was observed in R1D. In addition,
R1D had an increase (p,0.05) in RMR O
2
ml/kg/min (2.6 to 3.1). The 24 hour RMR decreased (p,0.05) in
the C1D group.
Conclusion: The addition of an intensive, high volume resistance training program resulted in preservation
of LBW and RMR during weight loss with a VLCD.
INTRODUCTION
Obesity is a major health problem in the United States
affecting more than 34 million Americans [1]. Weight loss
through dieting alone has been shown to result in a dramatic
and sustained reduction in resting metabolism [2,3]. Very-low-
calorie diets (VLCD) are often recommended in cases of ex-
treme clinical obesity [4]. Their use has primarily been limited
to persons who have failed to lose weight in more conventional
diet programs and whose body mass index (BMI) is greater
than 30 [5]. The problem often associated with the VLCD is the
significant loss of lean tissue and a subsequent decrease in
resting metabolism, especially in the early phase of the diet [6].
Endurance exercise in combination with severe energy restric-
tion has been shown to result in less decrease in fat free mass
(FFM) as compared with dieting alone [7,8]. However, a num-
ber of other studies have reported that endurance training in
conjunction with very-low-calorie diets have either produced
no effect [9–12] on the retention of FFM, or even caused an
augmented loss compared with the very-low-calorie diets alone
[13,14].
It has been suggested that resistance-training may be more
effective than aerobic exercise in preserving or increasing FFM
and resting metabolic rate (RMR) [15], especially in conjunc-
tion with a VLCD [16]. This combination, however, has not
been extensively studied. A limited number of studies have
Presented in part at the 44th Annual Meeting of the American College of Sports Medicine, May 27–31, 1997, Denver, CO.
Address reprint requests to: Randy W. Bryner, EdD, Department of Human Performance and Applied Exercise Science, PO Box 9227, 8317 HSC, Morgantown, WV 26506.
Journal of the American College of Nutrition, Vol. 18, No. 1, 115–121 (1999)
Published by the American College of Nutrition
115
combined resistance training with a VLCD and reported no
added benefit for the retention of FFM compared to the VLCD
alone [12,17]. However, resistance training during severe en-
ergy restriction and large-scale weight loss has been shown to
produce significant hypertrophy in the skeletal muscle in which
training occurred [18]. It does not attenuate the loss, however,
of FFM in non-exercised tissue. It is possible that previous
studies using resistance exercise protocols have utilized an
insufficient volume of exercise. A review of several weight loss
studies involving exercise concluded that those which produced
the greatest weight loss involved either intensive training pro-
grams or were of relatively long duration [19]. The purpose of
this study was to compare the effects of an intensive high
volume resistance training program with a standard treatment
control aerobic training program in subjects consuming a
VLCD for 12 weeks. Changes in body weight, FFM and RMR
were compared between groups.
METHODS
Participants
Twenty subjects (17 women, three men) with a mean age of
36.7611.5 years, weight of 95.1613.0 kg, and a BMI of
35.262.9 kg/m
2
were recruited through newspaper advertise-
ments to participate in a 12-week diet and exercise study. The
criteria for participation in the study were no involvement in a
regular exercise or weight loss program for at least 6 months
prior to the first visit and no known cardiovascular, endocri-
nologic or orthopedic disorders. After informed consent was
obtained, all potential subjects underwent a complete medical
examination to determine their ability to participate. Eligible
subjects were randomly assigned to one of two groups: stan-
dard treatment control plus VLCD (C1D, females58,
males52), or resistance exercise plus VLCD (R1D, fe-
males59, males51). Each subject was given a maximum stress
test, body composition analysis, and RMR determination prior
to the start of the study. Subject characteristics can be found in
Table 1.
Resting Metabolic Rate
The RMR of subjects was determined at baseline and week
12. Following an overnight fast of at least 12 hours, subjects
reported to the Human Performance Laboratory for the deter-
mination of RMR. Subjects were fitted with a Hans Rudolf face
mask which was connected to an Aerosport metabolic system
for the determination of breath by breath oxygen analysis.
Subjects rested quietly in a supine position for 30 minutes in a
thermo-neutral environment. The mean oxygen consumption
(VO
2
) was calculated over the final 5 minutes and was used to
determine the RMR. A menstrual history was taken for each of
the female subjects at the start of the study. The goal of the
study was to keep the phase of the menstrual cycle constant for
the baseline and week 12 RMR test. However, since the study
was exactly 12 weeks in duration, three of the females (one in
C1D; two in R1D) who had a regular cycle during the study
were post tested in the alternate cycle phase due to variations in
cycle length.
Peak Oxygen Consumption and
Hydrostatic Weighing
Peak oxygen consumption (PVO
2
) was determine at base-
line and at 12 weeks by a symptom limited treadmill graded
exercise test (GXT) using a modified Balke treadmill protocol
[20]. Participants received a verbal overview of the GXT pro-
cedure and were fitted with a noseclip and a Hans Rudolph
non-rebreathing mouthpiece for collection of expired air during
the GXT. Breath by breath oxygen analysis was done with an
Aerosport metabolic system. The protocol was initiated at a
comfortable but brisk walking speed at 0% elevation. Treadmill
speed remained constant throughout while the elevation was
raised 1% each minute until volitional fatigue. Criteria for
considering the GXT a maximal effort included at least two
of the following: a plateau in maximal oxygen consumption,
a respiratory ratio greater than 1.0, or voluntary discontin-
uation by the participant despite urging from the staff.
Hydrostatic weighing was used to determine percent fat and
fat free mass at baseline and at 12 weeks by a previously
validated method [21].
Diet
All participants were given the same diet for the entire
12-week study period. The VLCD consisted of a liquid formula
(40% protein, 49% carbohydrate, 11% fat) ingested five times
a day yielding a total of 800 kcals daily. Two multivitamin
tablets were also consumed daily. Diet and vitamins were
provided by Health Management Resources Inc., Boston, MA.
Participants were asked to refrain from other food or non diet
beverages. All subjects met with an investigator weekly and
Table 1. Subject Characteristics at Baseline (Mean6SD)
C1D
(N510)
R1D
(N510)
Age (years) 39.0611.6 35.8613.2
Body weight (kg) 93.8615.1 97.7615.2
BMI 35.263.9 35.562.0
Fat (%) 44.567.0 46.266.8
LBW (kg) 51.4610.6 51.667.9
Peak VO
2
(ml/kg/minute) 21.262.6 21.164.2
RMR (kcal/day) 1569.26202.39 1737.16393.4
RMR (ml/kg/minute) 2.260.5 2.660.5
C1D, standard treatment control plus VLCD; R1D, resistance treatment plus
VLCD
BMI, body mass index (kg/m
2
); LBW, lean body weight; VO
2
, oxygen consump-
tion; RMR, resting metabolic rate.
Resistance Training on Lean Body Mass and RMR
116 VOL. 18, NO. 1
were questioned about their medical condition and their com-
pliance to the dietary protocol. Only 1 week worth of supple-
ment was given at a time requiring subjects to be present at the
weekly weigh-in and meeting sessions. Adherence to the diet
was questioned if weight loss was less then 2 lbs per week.
Each subject was asked to give a verbal declaration of adher-
ence to the diet at each weekly meeting. Self-reported compli-
ance was excellent.
Exercise Training Protocols
Resistance Training plus Diet. The Resistance Training
(R1D) group performed resistance exercises 3 days/week at 10
stations which included four lower body and six upper body
exercises for 12 weeks. The initial 2 week were used to famil-
iarize subjects to the resistance training apparatus and to de-
termine the maximum weight that could be lifted either once
(1RM) or eight times (8RM). The 1RM was determined as
follows: Subjects performed one set of six to eight repetitions
with a weight that could be lifted 12 to 15 times. A second set
of two to three repetitions with a slightly heavier weight was
performed. The weight was then increased to a cautious esti-
mate of the 1RM at which time subjects attempted a single lift.
If successful, the weight was gradually increased until the
subject could not complete the one repetition lift. The 1RM test
was conducted during week 2 and again at the end of week 12.
The training protocol was as follows: During the initial
training session, subjects exercised by lifting a weight that was
considered light for one set of approximately 15 repetitions per
station. For the second workout, subjects performed two sets
using the same weight as the first workout for each station. A
gradual increase in weight was used until subjects were lifting
a weight that could be lifted at least eight times but no more
than 12 times as determined by the 8RM for two sets by the end
of week 2 of training. Three sets were done at week 6 and four
sets at week 9 all utilizing the same intensity and number of
repetitions as described previously. Rest periods of approxi-
mately 1 minute were given between each exercise throughout
the training session in a circuit-type workout. Careful monitor-
ing of subjects was done to insure that once an individual was
able to lift a weight 12 times on the final set, additional weight
was added on the next training session. In addition, heart rate
was monitored during the 1-minute resting periods periodically
throughout the exercise session by radial artery palpation. This
procedure was used throughout the 12-week training period to
maintain a consistent level of training intensity. Training ses-
sions were scheduled three times per week with a mandatory
1-day rest between visits to eliminate soreness and insure full
recovery due to the aggressive nature of the protocol. Very few
subjects complained of fatigue or soreness throughout the en-
tire 12-week period.
Standard Treatment Control plus Diet. The Standard
Treatment Control (C1D) group exercised 4 days/week by
walking, biking, or stair climbing. Exercise duration began at
20 minutes/day and increased 10 minutes/day/week until sub-
jects were exercising 50 to 60 minutes each session. A self-
paced protocol was used to simulate the HMR program in
which exercise intensity is not prescribed but exercise is en-
couraged. In addition, heart rate was monitored approximately
every 10 minutes during exercise by radial artery palpation. All
participants were individually monitored at each exercise ses-
sion to assure compliance with both the resistance and aerobic
training protocols.
Data Analysis
A series of independent repeated measures analysis of vari-
ance (ANOVA) calculations were used to assess the degree to
which exercise training (resistance vs. standard treatment con-
trol) produced changes in cardiovascular fitness, metabolic, and
weight variables over two time points (pre-post training). Be-
cause of the low number of male subjects, data were analyzed
both with males included and excluded. Results were similar,
therefore the following results reflect the entire subject pool. A
probability level of 0.05 was selected as the criterion for
statistical significance.
RESULTS
No differences were observed between groups at the start of
the study for body weight, percent fat, LBW, Max VO
2
,or
RMR (Table 1). Compliance to exercise sessions was excellent
in both groups during the 12-week study, averaging
92.5%617.9% and 91.4%621.8% for the C1D and R1D
groups, respectively with no difference between groups. The
C1D exercised at a greater (p,0.01) heart rate intensity com-
pare to R1D during the daily training sessions (78.4%65.9%
vs. 69.0%67.7%; mean6SD percent of max HR)
Maximum VO
2
and treadmill time to fatigue was measured
during the pretest and immediately after the 12-week study
period (Table 2). There was a significant increase (p,0.05) in
peak VO
2
for both of the C1D and R1D groups (C1D:
21.262.6 to 27.663.4 ml/kg/minute; R1D: 21.164.2 to
27.465.5 ml/kg/minute, mean6SD) which was of similar mag-
nitude. There was a significant group by test interaction
(p,0.05) for the treadmill time to fatigue. (C1D: 12.063.7 to
17.562.8 minutes; R1D: 10.962.7 to 13.866.1 minutes,
mean6SD). The C1D group had a significantly greater im-
provement than did R1D.
Body weight, body fat, LBM, BMI, and percentage of fat
measured during the pretest and post test can be found in Table
2. Although both groups lost a significant amount of weight
(p,0.05) there was a significant group by test interaction
(p,0.01) for body weight. As can be seen in Table 2, C1D
experienced a significantly greater decrease in body weight
than did R1D, (19.4 vs. 14.7%). Each group experienced a
similar reduction (p,0.05) in body fat (C1D: 40.869.1 to
Resistance Training on Lean Body Mass and RMR
JOURNAL OF THE AMERICAN COLLEGE OF NUTRITION 117
28.066.5 kg, R1D: 44.9610.9 to 30.465.3, kg), fat percent-
age (C1D: 44.567.0 to 37.166.0, R1D: 46.266.8 to
37.664.8), and BMI (C1D: 35.263.9 to 28.662.8, R1D:
35.562.0 to 29.761.7). There was also a significant (p,0.05)
group by test interaction for LBW. Lean body weight decreased
(p,0.05) in the C1D group (51.3610.7 to 47.367.0 kg,
mean6SD). No reduction in LBW was observed in the R1D
group (51.667.8 to 50.769.0 kg, mean6SD).
There was a significant group by test interaction for the
RMR expressed either as ml/kg/minute total weight (Fig. 1) or
ml/kg LBW/minute (Fig. 2). As can be seen in Fig. 1, RMR
increased (p,0.05) in the R1D group and was greater after 12
weeks compared with C1D. The RMR was also significantly
greater (p,0.05) in the R1D versus the C1D group after
12-weeks expressed as ml/kg LBW/minute (Fig. 2) or 24-hour
RMR (Table 2). The 24-hour RMR (Table 2) decreased signif-
icantly (p,0.05) in the C1D group (1569.26202.4 to
1358.56297.1 kcal/day, mean6SD).
The 1RM test results for leg press (LPRM), leg extension
(LERM), bench press (BPRM), and shoulder press (SPRM)
determined for R1D can be found in Table 3. There was a
significant (p,.01) increase in strength in all four measures pre
to post. The increases in strength ranged from 23.063.7% for
SPRM to 48.0630.1% for LERM. The average intensity during
Fig. 1 Resting metabolic rate (RMR, mean6SD) expressed as ml/kg/
minute for the resistance plus diet (R1D) and standard treatment
control aerobic plus diet (C1D) groups. RMR increased significantly
(p,0.05) pre to post in R1D. It was also significantly greater (p,0.05)
in the R1D than in the C1D group after 12 weeks. No change was
observed in the C1D group pre to post.
Fig. 2 Resting metabolic rate (RMR, mean6SD) expressed as ml/kg
LBW/minute for the resistance plus diet (R1D) and standard treatment
control aerobic plus diet (C1D) groups. RMR was significantly greater
(p,0.05) in the R1D than in the C1D group after 12 weeks. No
change was observed in the C1D group pre to post.
Table 2. Changes in Body Composition Data, RMR and Peak VO
2
(Mean6SD)
C1D(N510) R1D(N510)
Pre Post Pre Post
Body weight (kg) 93.8615.1 75.7610.6* 97.7615.2 83.3612.6*†
BMI 35.263.9 28.662.8* 35.562.0 29.761.7*
Fat (%) 44.567.0 37.166.0* 46.266.8 37.664.9*
LBW (kg) 51.4610.6 47.367.0* 51.667.9 50.869.0
Fat (kg) 40.869.1 28.066.47 44.9619.9 30.465.3
Peak VO
2
(ml/kg/minute) 21.262.6 27.663.4* 21.164.2 27.465.5*
Treadmill time (minutes) to fatigue 12.063.7 17.562.8* 10.962.7 13.866.1*†
RMR (kcal/day) 1569.26202.4 1358.56297.1* 1737.16393.4 1800.46362.0†
C1D, standard treatment control plus VLCD; R1D, resistance treatment plus VLCD.
BMI, body mass index (kg/m
2
); LBW, lean body weight; VO
2
, oxygen consumption; RMR, resting metabolic rate. * p,0.05, significantly different from pre test values;
†p,0.05, significant differences between groups.
Resistance Training on Lean Body Mass and RMR
118 VOL. 18, NO. 1
the final week of training for the R1D group for these four
measures was 75.968.3% of the maximum 1RMs.
DISCUSSION
The results from the present study indicate that the addition
of a high intensity high volume resistance training program to
a VLCD can attenuate the loss of LBM and increase RMR
while still producing a significant weight loss. Combining
aerobic exercise and a VLCD resulted in a significant decrease
in body weight, LBM, and RMR. Resistance exercise was also
associated with an increase in peak VO
2
similar to changes
seen in the standard treatment control aerobic group.
Other studies have reported that weight loss through the
combination of diet and aerobic exercise results in significant
loss of both body fat and LBM [9–12] similar to the present
findings. The percentages of fat and lean body mass lost on
VLCDs has been reported to be approximately 75% and 25%,
respectively [22]. These percentages can fluctuate and may be
affected by the amount of protein intake [23] and the amount of
physical activity performed during the VLCD period. The diet
used in the present study was composed of 40% protein or
approximately 80 g/day. Froidevaux and others [23] reported
that a low-energy diet supplemented with protein (7764g
protein/day) resulted in a body fat mass decrease of 1164kg
corresponding to 83619% of weight loss. This would indicate
that a diet supplemented with protein may contribute to the
maintenance of LBM during periods of severe energy restric-
tion. However, although diet composition can potentially affect
the type of tissue lost during conditions of negative energy
balance, such effects are usually very small given the short
duration of most obesity treatment programs and therefore of
minimal significance during the weight loss period [24]. Some
evidence indicates that aerobic training concurrent with VLCD
can cause greater loss in FFM than occurs with a VLCD alone
[13,14]. Resistance training may be more advantageous to use
during periods of severe energy restriction as it has been shown
to have a low metabolic cost and to create a smaller energy
deficit then aerobic training. This ultimately could help pre-
serve FFM.
The relative percent change in weight after 12 weeks of
VLCD was significantly greater in the standard treatment con-
trol aerobic training versus resistance training group. The
scheduled exercise sessions per week for the C1D and R1D
groups were four and three sessions, respectively. Subject
compliance to exercise was excellent for both groups and did
not differ. The resistance training group only exercised three
times weekly because the aggressive program necessitated a
day of rest between workouts. The C1D group exercised 4
days per week because this has been the experimental design
used in past studies with VLCD [12,17] and because the pur-
pose of this group was to serve as a standard treatment control.
In addition, subjects in C1D exercised at a greater intensity per
session (higher percent of maximum HR) as compared with the
resistance trained subjects. Therefore, it is likely that these
subjects expended more energy throughout the 12-week train-
ing program compared with R1D contributing to the greater
weight loss. It is also possible that subjects in C1D were under
a greater influence of catabolic hormones such as epinephrine
during and immediately following each workout. Previous
studies have reported that exercise can stimulate the sympa-
thetic nervous system and that the release of catecholamines,
especially epinephrine, during exercise is an intensity depen-
dent process [25,26]. There is a possibility that subjects in
R1D would have lost more weight had they exercised four
times per week as opposed to three. However, what is known is
that resistance training three times per week while consuming
a VLCD was associated with a significant large loss of clini-
cally relevant body weight and that this loss was almost entirely
fat weight.
Few studies have been conducted that combine resistance
training with weight loss and even fewer have examined this
type of exercise in combination with a VLCD. Ballor and
others [27] reported that resistance training can increase fat free
mass in subjects consuming a diet of approximately 1200
kcal/day. However, most studies that have combined a VLCD
(800 kcals or less) have reported that resistance training does
not attenuate the loss of LBM or decrease in RMR. Resistance
training combined with severe energy restriction (approximate-
ly 520 kcal/day) showed no greater retention of FFM than when
severe energy restriction was used by itself [12]. In a similar
study, Donnelly et al [17] reported that resistance training alone
or in combination with aerobic training showed no greater
effects in increasing weight loss or decreasing the loss of FFM
or RMR compared to VLCD alone. The same study also
reported no differences between aerobic and resistance training
for any of the aforementioned parameters. Comparisons with
these and the present study are difficult due to the different
experimental designs used in each study, especially the resis-
tance training protocols. The present study incorporated a pro-
gressive intensive resistance training protocol of high volume
designed to not only prevent the decline in FFM with weight
Table 3. Changes in Strength after 12 Weeks of Resistance
Training in the R1D Group (Mean6SD)
R1D(N510)
Pre Post % Change
SPRM (lbs) 62.7616.3 76.5622.0* 23.063.7
BPRM (lbs) 67.9616.5 95.0625.5* 42.4623.4
LPRM (lbs) 333.0670.4 468.5672.7* 38.7622.4
LERM (lbs) 94.2635.0 135.7632.6* 48.0630.1
R1D, resistance treatment plus VLCD.
SPRM5shoulder press one repetition maximum; BPRM5bench press one rep-
etition maximum; LPRM5leg press one repetition maximum; LERM5leg ex-
tension one repetition maximum.
*p,0.05, significantly different from pretest values.
Resistance Training on Lean Body Mass and RMR
JOURNAL OF THE AMERICAN COLLEGE OF NUTRITION 119
loss but enhance it if possible. Maintaining FFM and RMR may
be very important during periods of weight loss.
Previous research has shown that significant muscle hyper-
trophy is possible in an individual undergoing severe energy
restriction. Both slow twitch and fast twitch cross-sectional
fiber area increased significantly in muscles that were resistive
trained for 90 days in individuals who were consuming a
VLCD [18]. Similar to the present study, dietary intake was
approximately 800 kcals/day. However, hypertrophy was only
seen in exercised muscles and the resistance training was
unable to prevent the loss of overall FFM any better then diet
alone. Muscular activity during severe energy restriction may
decrease protein catabolism by decreasing the sensitivity of
working muscles to catabolic hormones [28]. However, it is
possible that some baseline level of dietary intake (i.e., 800 to
1200 kcals) is necessary for significant muscle hypertrophy to
occur with resistance training. Studies have reported that a
dietary intake of 1,000 to 1,500 kcals is needed to see the
positive benefits that exercise training can have on RMR and
FFM [29,30]. Alternatively, it is also possible that a more
aggressive resistance training protocol which incorporates
more muscle groups could attenuate this loss of FFM so often
seen during severe energy restriction. Results from the present
study showed, in fact, that this type of protocol was able to
maintain FFM in individuals who were consuming a VLCD
and losing a significant amount of weight.
A significant increase in peak VO
2
was observed in both the
aerobic and resistance trained individuals. Previous studies
combining resistance training only with a VLCD have not
reported increases in peak VO
2
[12,17]. The present protocol
required that the subject not only be challenged to lift more
weight but also to maintain a minimal rest period between sets
to incorporate a circuit type workout. This approach most likely
contributed to the increased oxygen consumption noted in the
resistance training group and may have contributed to the
maintenance of FFM.
Subjects in the R1D also experienced a significant increase
in both upper body and lower body strength as measured by the
four 1RM tests. The 1RM testing was conducted at the end of
the second week of training. This was done to allow for the
initial strength gains so often seen at the beginning of a resis-
tance training program, particularly in previously untrained
individuals. The causes of these increases have been associated
with the optimization of motor unit recruitment patterns or the
so called “neurological training” [31]. Subjects in the C1D
were instructed not to participate in any resistance training
during the course of the study. For this reason, 1RM testing was
not performed on these subjects because a single lifting mea-
surement would most likely have been invalid and not compa-
rable to those obtained from the R1D group.
In summary, the addition of high volume aggressive resis-
tance training to a VLCD was associated with a significant
weight loss while preserving LBW and RMR. The preservation
of LBW and RMR during the consumption of a VLCD did not
occur with a standard treatment control aerobic training pro-
gram. These results indicate that high volume resistance train-
ing may be beneficial for patients who use a VLCD to lose
large amounts of weight at least for periods up to 12 weeks.
Future clinical studies need to determine its efficacy in long
term weight loss programs and the maintenance of this weight
loss for extended periods of time.
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Resistance Training on Lean Body Mass and RMR
JOURNAL OF THE AMERICAN COLLEGE OF NUTRITION 121
... Various physical exercise programmes have been applied and studied over time; most of them are aerobic (Drobnik-Kozakiewicz, Sawczyn, Zarebska, Kwitniewska, & Szumilewicz, 2013;Patel et al., 2017), strength endurance EFFECTS OF EXERCISE PROGRAMMES ON BODY COMPOSITION | N. PRVULOVIC ET AL. (Bryner et al., 1999;Faigenbaum & Westcott, 2009), and combined training types (Ballor, Harvey-Berino, Ades, Cryan, & Calles-Escandon, 1996;Kim et al., 2016). There are also various types of training, such as circuit training, which includes various stations at which exercises are performed sequentially and for which rest depends on each exercise. ...
... Based on the results compiled from existing studies, we can unambiguously conclude that overweight individuals, individuals with a disbalance in the homeostasis of body composition, and individuals trying to prevent obesity should participate in prescribed physical exercise programmes. In addition, we should mention the trend indicated in existing literature in which the monitoring and control of one's diet accompanied with physical exercise contribute to achieving the best effects (Bryner et al., 1999). ...
... Extensively detailed studies that included controlling the participants' diet and their calorie intake along with combined or individual aerobic programmes and strength endurance training have also noted positive changes (Geliebter et al., 1997;Wadden et al., 1997;Kerksick et al., 2009;Bryner et al., 1999). A study was carried out on a large sample of female participants (161) divided into five groups (Kerksick et al., 2009). ...
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The present systematic review will compile, analyse, and synthesize current results regarding the effects of various exercise programmes on body composition and body mass. Method: searching electronic databases such as PubMed, MEDLINE, Google Scholar, ScienceDirect, ERIC and compiling studies on the effects of various exercise programmes on reduction of body mass and changes to body composition. The range of the dates of publication is 1994-2020. The studies included healthy adult individuals and excluded values for body weight. Results: based on 16 analysed studies outlining the advantages of aerobic programmes for reductions in body mass and endurance resistance programmes for improvement in body composition parameters, a combined type of exercise is recommended as the best option. The recorded intensity of exercise ranged from 40-80% of maximum heart rate (MaxHR), with a weekly workout frequency of 3-5 times for 40-60 min, for six to 48 weeks. Moderate-intensity aerobic training of 60% MaxHR gave the best results for reducing body mass, while interval training with greater intensity of 80% MaxHR showed inconsistent results. Circuit resistance training indicated both positive and negative results for improvement in body composition parameters; exercise intensity varied from 50-70% MaxHR. Conclusion: various exercise programmes provide an effective group type of work, leading to significant effects in reducing body mass and positive changes in body composition.
... It is critical to note that many weight loss programmes incorporating diet-only and/or even aerobic-only exercise results in weight loss as a result of a deleterious reduction in muscle mass [16], sometimes even without a decrease in fat mass [16]. When it comes to weight loss, it is clear that a combination of interventions is more effective than a single intervention strategy [17]. ...
... It is critical to note that many weight loss programmes incorporating diet-only and/or even aerobic-only exercise results in weight loss as a result of a deleterious reduction in muscle mass [16], sometimes even without a decrease in fat mass [16]. When it comes to weight loss, it is clear that a combination of interventions is more effective than a single intervention strategy [17]. ...
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In addition to the impact of normal ageing on body composition, increasing levels of sedentariness reduce an individual’s ability to mobilise fat, resulting in an altered body composition characterised by increased fat mass, and more specifically an increased total and abdominal fat, and reduced muscle mass. While exercise, and aerobic exercise in general, has been promoted as a means to maintaining an appropriate body weight, aerobic exercise should not be considered as the golden standard to do so. This is because resistance training (RT) has an unsurpassed ability to improve lean mass along with other simultaneous improvements in multiple body composition parameters. An increased muscle mass is essential in that it is the amount of exercising muscle that determines the magnitude of lipolysis (fatty acid release from adipocytes) during exercise. In addition, an increased muscle mass results in an elevated basal metabolic rate (BMR) and resting metabolic rate (RMR), effectively increasing the amount of energy or calories utilised even at rest. RT is especially useful in the general population for weight management in that the ideal form of RT required for improvements in body composition is of moderate intensity, which reduces the risk of injury and improves adherence.
... In two of the studies a comparison of endurance training and resistance training was made, Hersey III et al. (1994), Ballor et al. (1996). In both studies endurance training made significantly greater contribution to the changes in body composition or the decrease in body mass and body weight This is in agreement with the research (Bryner, Ullrich, Saures, Donley, Hornsby et al., 1999) in which evidence was found that aerobic training is far more effective in the decrease of body weight and fat body mass than resistance training. ...
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Body composition is one of the components of physical fitness and it refers to the tissue components which make up the body and is usually used to mark the relative percentage of fat and lean body tissue. In environments of health and fitness, the main interest is the acquisition of knowledge regarding the relative amount of body mass in relation to fat-free mass and the distribution of fat in the human body, with the additional interest in the changes in these components. Physical inactivity is one of the main causes of the increase in body fat. In the case of the elderly, the increase in body fat is conditioned by the slower walking speed and functional limitations. The subject matter of this paper are the studies published in the period from 1991 to 2010 which focused on the effects of physical exercise on the body composition of the elderly, aged 55 to 85. The aim of the paper is to analyze the methods, experimental treatment, results and conclusions which the authors reached in the evaluated studies. The research included a total of 28 papers. The results of the analyzed research indicated that the greatest positive effects on the changes in body composition were determined for exercise programs in combination with an appropriate diet. On the basis of the results of the analyzed research, the optimal duration of the exercise program should be at least 12 weeks, with a frequency of 3 or 4 training sessions per week. The intensity of the exercise in resistance training should progressively increase up to 80%1RM. Each exercise should be performed in three sets of 8 to 12 repetitions. In the case of endurance training, the intensity of the exercise should be at least 80%Hrmax, or in other words, the intensity of the exercise should be moderate to high, with an average training session duration of 60 minutes.
... Therefore aerobic exercise leads to reduction of weight and body fat, whereas resistance exercise leads to chronic increase in 24Hr energy expenditure and fat oxidization to tier important to help in maintaining energy balance and helps weight loss. In this study, subjects was incontestable a major weight loss in each group A and B. Previous study states that the result of resistance exercise and aerobic exercise on insulin sensitivity in overweight Korean Adolescents showed a marked reduction in BMI and a major reduction in muscle mass within the aerobic exercise group when compared to the resistance exercise group [13] . In our study, we have given 600 calorie less diet compared to their daily calorie intake. ...
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Background: The purpose of this study was to compare effectiveness of short term resistance training using elastic resistance band over aerobics on obesity in multidisciplinary program and assess if eight weeks of training are decent for reduction of muscle and fat mass. Methods: Thirty healthy and untrained obese adults (07males and 23 females) were included in study and then randomly assigned into an Elastic resistance training group (n=15) and Aerobic training group (n=15). Each subject underwent testing of BMI, WC, WHR, BMR before and after the intervention. Both the group completed an 8-week exercise training period. Result: Average age, height, weight and BMI for the elastic resistance training subjects were 32.99 ± 1.59 and for aerobic training subjects 32.65 ± 1.97 respectively. There was no significant difference in age and BMI between the two groups. In our study we found that aerobic exercise and resistance training resulted in reduction in BMI, WC and BMR parameter. The results of this study clearly demonstrated that there was no significant difference between the two treatments and both the interventions found effective in treating obesity. Conclusion: In conclusion, both resistance training using elastic band (Theraband) and aerobic exercise for 8 weeks is statistically significant in reduction of obesity.
... Even if the level of exercise training did not meet a minimal requirement to evoke an improvement in the 'major' NO-dependent vasodilative mechanisms, it is possible that low-intensity training was sufficient to maintain KCa-dependent initiation of J Physiol 600.12 vasodilatation in arterioles when local shear stress and calcium signalling were initiated by muscle contractions. Some studies suggest that a higher intensity of training (more than 50%V O 2 max ) and more sessions are required to improve the metabolic state (Bryner et al., 1999) and, indeed, a significant improvement of vascular function was found in obese Zucker rats as a result of exercise training with a running speed of 24 m min -1 (Xiang et al., 2005). Nevertheless, the KCa-dependent contribution to hindlimb blood flow response during skeletal muscle contractions was restored in our low-intensity exercise trained fa/fa rats. ...
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Obese women (140–180% of ideal body weight) were studied on a metabolic ward during 1 wk of maintenance feeding, followed by 5 wk of 800 kcal/d (liquid formula diet). Five subjects participated in a supervised program of daily aerobic exercise and three subjects remained sedentary. Total weight loss was not different between exercising and nonexercising subjects but significantly more of the weight loss came from fat and less from fat-free mass in the exercising subjects. Resting metabolic rate (RMR) declined similarly in both groups (approximately 20%), even though exercising subjects were in greater negative energy balance due to the added energy cost of exercise. In summary, results from this controlled inpatient study indicate that exercise is beneficial when coupled with food restriction because it favors loss of body fat and preserves fat-free mass.
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Skeletal muscle can undergo rapid growth in response to a sudden increase in work load. For example, the rat soleus muscle increases in weight by 40% within six days after the tendon of the synergistic gastrocnemius is sectioned. Such growth of the overworked muscle involves an enlargement of muscle fibers and occasional longitudinal splitting. Hypertrophy leads to greater maximal tension development, although decreased contraction time and reduced contractility have also been reported. Unlike normal developmental growth, work-induced hypertrophy can be induced in hypophysectomized or diabetic animals. This process thus appears independent of growth hormone and insulin as well as testosterone and thyroid hormones. Hypertrophy of the soleus can also be induced in fasting animals, in which there is a generalized muscle wasting. Thus muscular activity takes precedence over endocrine influences on muscle size. The increase in muscle weight reflects an increase in protein, especially sarcoplasmic protein, and results from greater protein synthesis and reduced protein breakdown. Within several hours after operation, the hypertrophying soleus shows more rapid uptake of certain amino acids and synthesis of phosphatidyl-inositol. By 8 hours, protein synthesis is enhanced. RNA synthesis also increases, and hypertrophy can be prevented with actinomycin D. Nuclear DNA synthesis also increases on the second day after operation and leads to a greater DNA content. The significance of the increased RNA and DNA synthesis is not clear, since most of it occurs in interstitial and satellite cells. The proliferation of the non-muscle cells seems linked to the growth of the muscle fibers; in addition, factors causing muscle atrophy (e.g. denervation) decrease DNA synthesis by such cells. In order to define more precisely the early events in hypertrophy, the effects of contractile activity were studied in rat muscles in vitro. Electrical stimulation enhanced active transport of certain amino acids within an hour, and the magnitude of this effect depended on the amount of contractile activity. Stimulation or passive stretch of the soleus or diaphragm also retarded protein degradation. Presumably these effects of mechanical activity contribute to the changes occuring during hypertrophy in vivo. However, under the same conditions, or even after more prolonged stimulation, no change in rates of protein synthesis was detected. These findings with passive tension in vitro are particularly interesting, since passive stretch has been reported to retard atrophy or to induce hypertrophy of denervated muscle in vivo. It is suggested that increased tension development (either passive or active) is the critical event in initiating compensatory growth.
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1. Six well-trained cyclists and six untrained subjects were studied during and immediately after four successive 7 min periods of exercise at 30, 45, 60 and 75% of their maximal work capacity. 2. Venous blood samples were taken at rest, at the end of each exercise period and 5 min following the end of exercise, for estimation of metabolites in blood and plasma insulin, growth hormone, cortisol and catecholamines. 3. The results showed significant differences in the mobilization and utilization of muscle fuels between the athletically fit cyclists and the untrained group. In the cyclists, glucose, glycerol and free fatty acid concentrations were higher, but lactate, pyruvate and alanine were lower than in the untrained subjects during exercise. 4. Plasma catecholamines rose in both groups during exercise but the rise was significantly less in the racing cyclists. Plasma insulin was depressed to a greater extent in the untrained subjects during exercise and plasma glucagon rose to a greater extent during strenuous exercise and remained elevated after the end of exercise in the untrained group. Plasma human growth hormone rose to a greater extent during exercise and remained elevated after the end of exercise in the untrained group. Plasma cortisol fell at low and moderate exercise rates in both groups, but to a smaller extent in the cyclists. Cortisol values rose at higher workloads and were significantly higher in the cyclists at the end of exercise. 5. It is concluded that there are significant differences in the metabolic and hormonal responses to exercise between athletically trained and untrained individuals, even when the physically fit subjects work at the same percentage of their maximal capacity as the unfit subjects.
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Data from the Second National Health and Nutrition Examination Survey (NHANES II) indicated that in the period 1976-1980 approximately 34 million US adults (25.7%) were overweight, with more women (19 million) than men (15 million) affected. Selected demographic factors, eg, low educational attainment and low family income were associated with the prevalence of overweight and with the incidence of weight gain. Analyses of the NHANES I Epidemiologic Follow-up Survey indicated that in a 10-y period, women had a greater mean weight gain. The overall incidence of a major weight gain (ie, an increase of five or more body mass index units) was twice as great among females (5.3%) than males (2.3%). Data on overweight and weight gain in the United States by selected demographic characteristics are summarized.
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Very-low-calorie diets (VLCDs) provide a rapid decrease in total body weight, but limited data are available regarding the extent of fat loss and whether body fat distribution is altered. The purpose of this study was to investigate body composition, body fat distribution, and resting metabolic rate in obese men and women and to compare bioelectrical impedance analysis (BIA) with hydrodensitometry before and after 12 weeks of treatment in a VLCD program. Body composition was assessed by hydrodensitometry and BIA. Circumference measures were used to determine waist:hip and waist:thigh ratios. Seventeen subjects lost a mean of 24.2 kg. A mean of 75.5% of the weight loss was adipose tissue as measured by hydrodensitometry. BIA underestimated body fat percentage compared with hydrodensitometry in this obese population. Waist:hip and waist:thigh ratios showed a small but significant decrease, implying a decreased risk for diabetes and cardiovascular disease after weight loss. Resting metabolic rate, as measured by oxygen consumption, dropped 23.8% during the 12 weeks of the VLCD. The findings indicate that a VLCD can provide a rapid weight loss of more than 75% fat and a concomitant decrease in waist:hip and waist:thigh ratios. The findings also indicate that BIA may not be a useful tool in assessing fat loss in obese subjects. Finally, it appears that the decrease in resting metabolic rate that occurs during treatment with VLCD does not correlate with changes in lean body mass.
Article
In addition to the direct energy cost of physical activity, exercise may influence resting energy expenditure in 3 ways: (a) a prolonged increase in postexercise metabolic rate from an acute exercise challenge; (b) a chronic increase in resting metabolic rate associated with exercise training; and (c) a possible increase in energy expenditure during nonexercising time. It seems apparent that the greater the exercise perturbation, the greater the magnitude of the increase in postexercise metabolic rate. An exercise prescription for the general population that consists of exercise of low (<50% V̇O2max) or moderate intensity (50 to 75% V̇O2max) does not appear to produce a prolonged elevation of postexercise metabolic rate that would influence body-weight. Inconsistent results have been found with respect to the effects of exercise training and the trained state on resting metabolic rate. Whereas some investigators have found a higher resting metabolic rate in trained than untrained individuals and in individuals after an exercise training programme, other investigators have found no chronic exercise effect on resting metabolic rate. Differences in experimental design, genetic variation and alterations in energy balance may contribute to the discrepant findings among investigators. A relatively unexplored area concerns the influence of exercise training on energy expenditure during nonexercising time. It is presently unclear whether exercise training increases or decreases the energy expenditure associated with spontaneous or nonpurposeful physical activity which includes fidgeting, muscular activity, etc. The doubly labelled water technique represents a methodological advance in this area and permits the determination of total daily energy expenditure. Concomitant with the determination of the other components of daily energy expenditure (resting metabolic rate and thermic effect of a meal), it will now be possible to examine the adaptive changes in energy expenditure during nonexercising time. A plethora of studies have examined the combined effects of diet and exercise on body composition and resting metabolic rate. The hypothesis is that combining diet and exercise will accelerate fat loss, preserve fat-free weight and prevent or decelerate the decline in resting metabolic rate more effecively than with diet restriction alone. The optimal combination of diet and exercise, however, remains elusive. It appears that the combination of a large quantity of aerobic exercise with a very low calorie diet resulting in substantial loss of bodyweight may actually accelerate the decline in resting metabolic rate. These findings may cause us to re-examine the quantity of exercise and diet needed to achieve optimal fat loss and preservation of resting metabolic rate.
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Sixty-nine obese females received 90 d of a liquid diet providing 2184 kJ/d in clinical trials. Groups were diet only (C), diet plus endurance exercise (EE), diet plus weight training (WT), or diet plus endurance exercise and weight training (EEWT). Changes in body weight, percent fat, fat weight, and fat-free mass were not different between groups. Declines in resting metabolic rate (RMR) were approximately 7% to approximately 12% of baseline values with no differences among groups. A significant increase in work capacity (approximately 16%) was shown for EEWT. Strength index showed declines of approximately 6% for C and EE and gains of approximately 3% and approximately 10% for EEWT and WT, respectively. These clinical trials did not show advantages of any exercise regimen over diet alone for weight loss, body-composition changes, or declines in RMR. Improvements in work capacity were limited and strength improved in groups that participated in strength training.
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Obesity is an extremely prevalent condition that is associated with a range of deleterious health effects. While traditionally considered a disorder primarily of energy intake, accumulating evidence underscores the importance of energy expenditure in the development and treatment of obesity. As the most variable component of energy expenditure, physical activity can influence the development of obesity as well as success in achieving both initial and long term weight loss. Among the types of exercise-related physiological and behavioural factors most likely to be involved in the development of obesity are reductions in the amount of physical activity actually performed, differences in the effect of physical activity on diet-induced thermogenesis, and modeling of deleterious dietary and exercise patterns on the part of the family and other facets of the environment. In contrast, there is relatively little evidence supporting the common belief that obese individuals have a significantly greater energy intake than nonobese individuals. With respect to weight reduction in the already obese, while increased physical activity levels often augment caloric restriction programmes in aiding initial weight loss, evidence suggests that physical activity may be particularly important in helping to sustain initial losses through increased total energy output, preservation of lean body mass, and changes in substrate utilisation. The psychological benefits received from regular participation in a physical activity programme may serve as an additional impetus for engaging in such activities over the long run. Developing programmes to aid in long term adherence to physical activity regimens remains the most critical challenge. Recent results suggest the utility of regular, brief contacts in aiding sustained physical activity participation in individuals attempting to control their weight.