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The purpose of this study was to determine the effects of different amounts of energy intake in combination with progressive resistance training on muscle mass and body fat in bodybuilders. Eleven male bodybuilders (26.8 ± 2.3 years, 90.1 ± 9.7 kg, and 176.9 ± 7.1 cm) were randomly assigned into one of two groups: a group that ingested higher amounts of energy (G1, 67.5 ± 1.7 kcal/kg/d, n = 6), and a group that ingested moderate amounts of energy (G2, 50.1 ± 0.51 kcal/kg/d, n = 5). Both groups performed resistance training 6 days per week over a 4-week study period. Measures of body composition were assessed before and after the intervention period. For body fat, only the G1 presented significant changes from pre- to post-training (G1 = +7.4% vs. G2 = +0.8%). For muscle mass, both groups showed significant increases after the intervention period, with G1 presenting a greater increase compared to G2 (G1 = +2.7% vs. G2 = +1.1%). Results suggest that greater energy intake in combination with resistance training induces greater increases in both muscle mass and body fat in competitive male bodybuilders.
Journal of Human Kinetics volume 70/2019, 125-134 DOI: 10.2478/hukin-2019-0038 125
Section II Exercise Physiology & Sports Medicine
1 - Center for Research in Health Sciences. University of Northern Paraná, Londrina, Brazil.
2 - Metabolism, Nutrition, and Exercise Laboratory, Physical Education and Sport Center. Londrina State University, Londrina,
3 - Exercise Science Department, CUNY Lehman College, Bronx, New York, USA.
Authors submitted their contribution to the article to the editorial board.
Accepted for printing in the Journal of Human Kinetics vol. 70/2019 in December 2019.
Effects of Different Dietary Energy Intake Following Resistance
Training on Muscle Mass and Body Fat in Bodybuilders:
A Pilot Study
Alex S. Ribeiro1, João Pedro Nunes2, Brad J. Schoenfeld3, Andreo F. Aguiar1,
Edilson S. Cyrino2
The purpose of this study was to determine the effects of different amounts of energy intake in combination
with progressive resistance training on muscle mass and body fat in bodybuilders. Eleven male bodybuilders (26.8 ± 2.3
years, 90.1 ± 9.7 kg, and 176.9 ± 7.1 cm) were randomly assigned into one of two groups: a group that ingested higher
amounts of energy (G1, 67.5 ± 1.7 kcal/kg/d, n = 6), and a group that ingested moderate amounts of energy (G2, 50.1 ±
0.51 kcal/kg/d, n = 5). Both groups performed resistance training 6 days per week over a 4-week study period. Measures
of body composition were assessed before and after the intervention period. For body fat, only the G1 presented
significant changes from pre- to post-training (G1 = +7.4% vs. G2 = +0.8%). For muscle mass, both groups showed
significant increases after the intervention period, with G1 presenting a greater increase compared to G2 (G1 = +2.7%
vs. G2 = +1.1%). Results suggest that greater energy intake in combination with resistance training induces greater
increases in both muscle mass and body fat in competitive male bodybuilders.
Key words: strength training; bodybuilding; muscle mass; body fat; split routine.
Bodybuilding is an aesthetic sport
whereby competitors aspire to achieve a
combination of high levels of muscularity,
symmetry between muscles, and very low levels
of body fat (Hackett et al., 2013). Provided similar
muscular symmetry, proportion and definition,
the competitor with the largest muscles
necessarily has a decided advantage over his
Bodybuilding preparation generally
involves two phases. An off-season phase, in
which hypertrophy is the primary goal, and a pre-
contest phase, where the main objective is to
reduce body fat levels while maintaining muscle
mass. Thus, maximizing muscle growth,
especially during the first phase, is critical for
success in the sport. Accordingly, the proper
manipulation of resistance training variables as
well as precise attention to nutrient and energy
intake are essential off-season considerations.
Energy intake has an important effect on
the capacity to build muscle (Millward et al.,
1994). For example, studies have shown that
caloric restriction induces a chronic decrease in
muscle protein synthesis (McIver et al., 2012;
Pasiakos and Carbone, 2014), which necessarily
would limit muscle growth given that a positive
muscle protein balance over time is what
ultimately drives hypertrophic changes. On the
other hand, a positive energy balance, even in the
absence of strength training, is a potent stimulator
of anabolism (Churchward-Venne et al., 2013;
Millward et al., 1994).
126 Effects of different dietary energy intake following resistance training on muscle mass and body fat...
Journal of Human Kinetics - volume 70/2019
Several studies have shown that higher
energy intake in combination with progressive
resistance training induces greater increases in
hypertrophy when compared to lower caloric
conditions (Garthe et al., 2013; Rozenek et al.,
2002). However, overconsumption of energy also
can be accompanied by an increased fat
deposition (Garthe et al., 2013). Therefore,
elucidating a caloric surplus threshold that would
induce maximal hypertrophy with minimal
increases in body fat would be beneficial for
coaches and athletes to optimize body
composition. However, such a threshold remains
undetermined. Moreover, the adaptive response
to resistance training is dependent on an
individual’s training experience, whereby
untrained individuals are more responsive to
resistance exercise compared to those with
resistance training experience, displaying a higher
hypertrophic potential and a faster rate of muscle
growth (Ahtiainen et al., 2003). Thus, highly
trained individuals conceivably would need more
energy for building muscle.
Despite the aforementioned information,
there is a dearth of research as to how energy
consumption impacts body composition in highly
trained individuals. Therefore, the purpose of this
study was to investigate the effects of distinct
levels of energy intake in combination with
resistance training on muscle mass and body fat
in elite male bodybuilders.
Eleven male bodybuilders (26.8 ± 2.3
years) volunteered to participate in the study; all
athletes were competitors in Brazil, affiliated with
an amateur bodybuilding federation (IFBB Brazil).
The participants were randomly assigned into one
of two groups: a group that ingested higher
amounts of energy (G1, n = 6), and a group that
ingested moderate amounts of energy (G2, n = 5).
The following inclusion criteria were required for
participation: bodybuilding competitors for at
least one year; reported to having abstained from
anabolic steroid use for a minimum of 3 months
leading up to the study; non-smokers; and
currently abstained from consumption of
alcoholic beverages. All participants were in their
off-season period aiming to increase muscular
hypertrophy, and all had been regularly training 6
days per week with varied routines. Written
informed consent was obtained from all
participants after a detailed description of study
procedures. This study was performed in
accordance with the declaration of Helsinki, and
the experimental protocol was approved by the
Londrina State University Ethics Committee.
Body composition
Body mass was measured to the nearest
0.1 kg using a calibrated electronic scale (Balmak,
Laboratory Equipment Labstore, Curitiba, PR,
Brazil), with participants wearing light workout
clothing and no shoes. Height was measured with
a stadiometer attached to the scale; values were
obtained to the nearest 0.1 cm with participants
standing shoeless and head aligned in the
horizontal Frankfurt plane. The body mass index
was calculated as body mass in kilograms divided
by the square of height in meters.
Skeletal muscle mass was estimated using
the prediction equation of Lee et al. (2000),
validated by Gobbo et al. (2013) as follows:
SMM (kg) = 0.244 x BW + 7.8 x H + 6.6 x S – 0.098 x
A + R – 3.3
where BW = body weight (kg), H = height (m), S =
sex (male = 1, female = 0), A = age (years), R = race
(1.2 for Asians, 1.4 for African-Americans and 0
for Caucasians).
Body fat was estimated by the skinfold
technique using a Lange skinfold caliper at 7 sites
(chest, axilla, triceps, sub-scapula, abdomen,
supra-iliac, and thigh). The equation of Jackson
and Pollock (1978) was used to estimate body
density. Three measures were taken by the same
evaluator at each point, in a rational sequence, on
the right side of the body. The median value was
recorded. The equation of Brozek et al. (1963) was
then used to determine body fat.
Resistance training program
Resistance training was carried out for 4
weeks employing a program designed to promote
muscular hypertrophy. All participants were
personally supervised by physical education
professionals throughout each training session to
reduce deviations from the study protocol and to
ensure participant’s safety.
Resistance training was performed six
times a week parceled into three routines (A, B,
by Alex S. Ribeiro et al. 127
© Editorial Committee of Journal of Human Kinetics
and C). Routine A was carried out on Mondays
and Thursdays and included exercises for the
chest, shoulders, triceps, and abdomen in the
following order: bench press, incline dumbbell fly,
cable crossover, barbell military press, lateral
raise, lying triceps French press, triceps
pushdown, crunch, and cable crunch. Routine B
was performed on Tuesdays and Fridays and
consisted of exercises for the back, biceps, and
forearms in the following order: lat pulldown,
bent over barbell row, seated cable row, arm curl,
inclined dumbbell curl, seated palm-up barbell
wrist curl, and seated palm-down barbell wrist
curl. Routine C was carried out on Wednesdays
and Saturdays and comprised exercises for the
thigh and calf in the following order: squat, leg
press, knee extension, stiff leg deadlift, lying leg
curl, standing calf raise, and seated calf raise. All
exercises consisted of 4 sets with the magnitude of
load increasing and the number of repetitions
decreasing simultaneously for each set (ascending
pyramid method). The number of repetitions for
each set was 12/10/8/6 repetition maximum (RM),
respectively. In accordance with the ascending
pyramid routine, training loads were
progressively increased for each set by 2-4 kg for
upper body exercises and 4-10 kg for lower body
exercises. The number of repetitions per set was
higher for exercises of the wrist and calves (15-20
RM), and the abdominals (150 to 300 repetitions
per session). The greater volume of repetitions for
the wrist, calves and abdominals was based on the
premise that these muscles are more endurance-
oriented and thus need a greater time under
tension to maximize muscular development.
Participants were instructed to perform each
repetition with a velocity of 1 and 2 s in the
concentric and eccentric phases, respectively.
Participants were afforded a rest interval of 1-2
min between sets and 2-3 min between each
Dietary control
All diets were individually prescribed by
a nutritionist. The diets, in printed sheets, were
delivered to the athletes before the first week of
training. The diet plans were weekly readjusted
according to body weight changes. Participants
were oriented to distribute the meals every 3-4 h.
Foods included: rice, bean, potato, manioc, pasta,
fruits, vegetables, nuts, oats, juices, meats, eggs,
milk, yogurt, and oils. Total dietary energy,
protein, carbohydrate and fat content were
calculated using nutrition analysis software
(Avanutri Processor Nutrition Software, Rio de
Janeiro, Brasil; Version 3.1.4).
Design and Procedures
The study was carried out over a period
of 6 weeks, with 4 weeks dedicated to the
resistance-training program and 2 weeks allocated
for measurements and evaluations.
Anthropometric and body composition
measurements were performed at weeks 1 and 6,
while the resistance training program was carried
out during weeks 2-5. All sessions were directly
supervised by trained fitness personnel.
Participants refrained from performing any other
type of exercise during the entire study period.
The resting metabolic rate was individually
predicted for each athlete using the Harris and
Benedict equation (Harris and Benedict, 1918).
Statistical analysis
Two-way analysis of variance (ANOVA)
for repeated measures was used for intra- and
inter-group comparisons followed by Fisher’s
post hoc. Baseline scores as well as the relative
change differences between groups were explored
with an independent t-test. Effect size (ES) was
calculated as post-training mean minus pre-
training mean divided by the pooled pre-training
standard deviation (Cohen, 1992), where an ES of
0.00 - 0.19 was considered trivial, 0.20-0.49 small,
0.50-0.79 moderate and 0.80 large (Cohen, 1992).
For all statistical analyses, significance was
accepted at p 0.05. The data were analyzed using
STATISTICA software version 10.0 (Statsoft Inc.,
Tulsa, OK, USA).
Table 1 displays participant characteristics
at baseline. No significant differences were
observed between groups (p > 0.05) for age, body
mass, height, and resting metabolic rate at
baseline. However, as expected, the G1 had a
greater surplus of energy beyond the resting
metabolic rating compared to the G2.
Total macronutrients and energy intake of
both groups are displayed in Table 2. The G1
ingested significantly (p < 0.001) higher relative
amounts of carbohydrate, energy, and non-
protein kcal, but lower relative amounts of
protein (p < 0.01) and lipids compared to the G2.
Table 2 shows the pre- and post-training
128 Effects of different dietary energy intake following resistance training on muscle mass and body fat...
Journal of Human Kinetics - volume 70/2019
values for muscle mass and body fat according to
the group. For body fat, only the G1 showed
significant (p < 0.01) changes from pre- to post-
training, in which an increase was observed. Both
groups significantly increased measures of muscle
mass after the intervention period, with the G1
showing greater increases (p = 0.03) compared to
the G2.
Table 4 presents the effect size and values
for groups as well as the difference between
groups. A difference of small magnitude was
observed for muscle mass and body fat.
Pre- to post-study percentage changes in body
fat and muscle mass for each group are presented
in Figure 1. The G2 presented greater changes
than the G2 both for muscle mass (p = 0.04) and
body fat (p = 0.04). Figure 2 illustrates the
individual percentage changes from pre- to post-
training in muscle mass and body fat according to
the group.
Table 1
General characteristics of the participants at baseline. Data are presented as mean
and standard deviation.
G1 (n = 6) G2 (n = 5) p
Age (years) 26.5 ± 2.8 27.2 ± 1.7 0.64
Body mass (kg) 90.2 ± 13.3 89.8 ± 3.8 0.94
Height (cm) 179.1 ± 9.2 174.2 ± 2.3 0.27
RMR (kcal) 2025.0 ± 218.1 1989.9 ± 69.5 0.73
Energy above RMR (kcal) 4062.6 ± 635.6 2511.6 ± 109.5 < 0.001
Note: RMR = resting metabolic rate. G1 = higher energy intake. G2 = moderate energy intake
Table 2
Dietary intake of bodybuilders according to groups. Data are presented as mean
and standard deviation.
G1 (n = 6) G2 (n = 5) p
Grams 1170.2 ± 161.5 726.0 ± 30.8 < 0.05
g/kg 12.9 ± 0.32 8.0 ± 0.05 < 0.05
Energy (kcal) 4681.0 ± 646.2 2904.2 ± 123.4 < 0.05
Energy (%) 76.9 ± 0.99 64.5 ± 0.81 < 0.05
Grams 162.2 ± 26.1 185.0 ± 6.9 0.08
g/kg 1.8 ± 0.15 2.0 ± 0.05 < 0.05
Energy (kcal) 648.8 ± 104.4 740.1 ± 27.7 0.08
Energy (%) 10.6 ± 0.80 16.4 ± 0.39 < 0.05
Grams 84.1 ± 13.5 95.2 ± 5.8 0.12
g/kg 0.93 ± 0.05 1.06 ± 0.05 < 0.05
Energy (kcal) 757.7 ± 121.6 857.0 ± 52.3 0.12
Energy (%) 12.4 ± 0.59 19.0 ± 0.81 < 0.05
kcal 6087.6 ± 853.3 4501.4 ± 177.9 0.05
kcal/kg 67.5 ± 1.7 50.1 ± 0.51 < 0.05
Non-protein kcal/g protein 33.7 ± 3.1 20.3 ± 0.6 < 0.05
Note: G1 = higher energy intake. G2 = moderate energy intake.
by Alex S. Ribeiro et al. 129
© Editorial Committee of Journal of Human Kinetics
Table 3
Participants’ scores at baseline (pre) and post the 4-week intervention period.
Data are expressed as mean and standard deviation
G1 (n = 6) G2 (n = 5) p
Pre Post Δ% Pre Post Δ%
Muscle mass (kg) 36.7 ± 3.7 37.7 ± 3.9* +2.7 36.1 ± 1.1 36.5 ± 1.2* +1.1 < 0.05
Body fat (%) 16.2 ± 4.6 17.4 ± 4.6* +7.4 13.3 ± 2.7 13.4 ± 2.6 +0.8 < 0.05
Note: * p < 0.05 pre vs post. G1 = higher energy intake. G2 = moderate energy intake.
Table 4
Effects size values according to groups
G1 (n = 6) G2 (n = 5) Differences
Skeletal muscle mass 0.42 0.17 0.25
Body fat 0.33 0.03 0.30
G1 = higher energy intake. G2 = moderate energy intake
Figure 1
Percentage changes from pre- to post-training according to groups. G1 = higher energy
intake. G2 = moderate energy intake. * p < 0.05 pre- vs post-training. # p < 0.05 G1 vs.
G2. Data are presented as mean and standard deviation.
Effects of different dietary energy intake following resistance training on muscle mass and body fat...
Journal of Human Kinetics - volume 70/2019
Figure 2
Individual percentage changes from pre- to post-training on muscle mass (Panel A)
and body fat (Panel B) according to the group. G1 = higher energy intake. G2 =
moderate energy intake.
To our knowledge, this is the first study to
investigate the effects of alterations in energy and
macronutrient intake on body composition in
highly trained competitive bodybuilders. The
main and novel finding was that greater energy
intake elicited greater increases in both muscle
mass and body fat. The lack of previous literature
in the population studied makes a detailed
comparison with literature difficult. However,
several experiments in a non-bodybuilding
population indicate that energy surplus is
associated with higher muscle growth (Garthe et
al., 2013; Rozenek et al., 2002). Rozenek et al.
(2002) reported that untrained young adult males
increased fat-free mass (estimated by hydrostatic
weighing) after 8 weeks of resistance training
combined with an energy surplus of ~2000 kcal/d,
while a control group consuming a eucaloric diet
did not significantly change fat-free mass.
Interestingly, the group consuming an energy
surplus did not gain body fat, indicating that all
of the additional calories were used for the
development of fat-free mass. In a study of elite
athletes participating in a variety of sports
(rowing, kayaking, soccer, volleyball, taekwondo,
skating, and ice hockey), Garthe et al. (2013)
allocated participants to a diet providing a ~500
kcal/d surplus or ad libitum intake. All subjects
participated in the same 4-day-per-week
hypertrophy-type resistance training program,
which was carried out over a period of 8 to 12
weeks. Results indicated a greater increase in
lower body fat-free mass (estimated by dual-
energy X-ray absorptiometry) favoring those
consuming a caloric surplus versus those at
maintenance (0.5 kg vs. 0.0 kg, respectively).
However, the greater energy surplus was also
accompanied by an increase in body fat
deposition compared to the control condition (1.1
kg vs. 0.2 kg, respectively). The mechanism by
which energy surplus induces greater
hypertrophic changes is seemingly related to an
augmented muscle protein synthetic response
during periods of positive energy balance
(Millward et al., 1994). Evidence shows that even
in the absence of regimented resistance exercise, a
by Alex S. Ribeiro et al. 131
© Editorial Committee of Journal of Human Kinetics
positive energy balance alone drives increases in
lean mass provided sufficient dietary protein is
consumed (Churchward-Venne et al., 2013).
Moreover, muscle growth is an ATP-dependent
process (Lambert et al., 2004), thus adequate
energy needs to be available to build muscle
beyond what is expended by bodily tissues and
physical activity.
The relative energy intake in our
experiment was 67.5 kcal/kg/d and 50.1 kcal/kg/d
for the G1 and the G2, respectively. The G2
energy intake was in accordance with previous
findings in literature, but intake of the G1 was
above that previously observed. For example,
Slater and Phillips (2011) reviewed 7 studies that
investigated relative energy intake in male
bodybuilders and reported consumption ranged
from ~30 to ~60 kcal/kg/d. More recently, a review
by Spendlove et al. (2015) determined that energy
intake in male bodybuilders across 16 studies
ranged from ~24.3 to ~65.7 kcal/kg/d. This wide
range of energy consumption observed in the
literature may be related to the competition
phases, in which energy intake is typically greater
in the off-season compared to pre-contest, as well
as differences in the size of subjects between
Given the large inter-individual
variability generally seen in exercise and
nutritional trials, insight into each participants’
responsiveness is of relevance to draw evidence-
based inferences. Individual analysis indicated
that the G2 displayed the most non-uniform
variability. For example, all participants in the G1
increased muscle mass. Alternatively, one
participant in the G2 lost muscle mass, while the
second greatest increase in muscle mass of all
individuals in the study was observed for a
participant in the G2. A large inter-individual
variability was also noted for body fat changes in
the G2; while two participants reduced body fat
from pre- to post-study, the other three
participants showed an increase. Participants in
the G1 displayed more consistent body
composition outcomes, individually showing
accretion of both muscle mass and body fat.
Adequate intake of macronutrients is of
foremost importance for maximizing muscle
hypertrophy. Differences observed between
groups as to energy intake was chiefly due to
variation in carbohydrate intake. Carbohydrates
are an important substrate for maintaining
training intensity in resistance exercise. Research
shows that approximately 80% of ATP used in a
typical hypertrophy-oriented resistance exercise
session is obtained from glycolysis (Lambert and
Flynn, 2002; MacDougall et al., 1999; Pascoe et al.,
1993). Leveritt and Abernethy (1999) found that
reductions in muscle glycogen stores significantly
impaired performance in resistance exercise.
Nevertheless, although dietary carbohydrate has
been shown to enhance exercise performance,
only moderate amounts appear to be required to
achieve beneficial effects. For example, Mitchell et
al. (1997) found that a diet consisting of 7.66 g/kg
of CHO had no greater effect on the amount of
work performed during 15 sets of 15 RM lower-
body exercise when compared to consuming 0.37
g/kg. It should be noted that this was an acute
finding; it is not clear whether alterations in
carbohydrate intake affected training capacity
between groups in the present study and, if so,
whether this influenced lean mass gains.
Meeting daily needs for protein intake is a
key factor for promoting an accretion of lean mass
(Jager et al., 2017; Morton et al., 2018).
Hypertrophy-based recommendations suggest
relative protein intake ranging from 1.4 up to 2.0
g/kg/d in resistance practitioners (Jager et al.,
2017; Thomas et al., 2016), where consuming
beyond this amount would not induce further
benefits. Specific to novice bodybuilders, Lemon
et al. (1992) found that daily needs were
approximately 1.6 to 1.7 g/kg/d in the early phase
of training. Similar findings were reported by
Tarnopolsky et al. (1992). Most recently,
Bandegan et al. (2017) estimated protein needs in
male bodybuilders to be 1.7 g/kg/d with an upper
95% confidence interval of 2.2 g/kg/day as
determined by the indicator amino acid oxidation
technique. Both groups in the present
investigation met protein recommendations as
outlined in the literature. However, results
revealed that the G1 which ingested 1.8 g/kg/d
achieved a greater increase in muscle mass than
the G2 consuming 2.0 g/kg/d. This finding would
seem to indicate that once adequate daily needs
have been achieved (Jager et al., 2017; Morton et
al., 2018), additional increases do not contribute to
greater hypertrophy and non-protein kcal may be
a key factor for building muscle. It is noteworthy
that the difference between groups for protein
132 Effects of different dietary energy intake following resistance training on muscle mass and body fat...
Journal of Human Kinetics - volume 70/2019
intake was narrow; it is possible that wider
variances may elicit different alterations in body
composition (Antonio et al., 2015). The optimal
protein intake for high-caliber bodybuilders to
optimize body composition remains to be
determined; future trials are warranted to better
elucidate this topic.
The present study has some limitations
that should be taken into account when drawing
evidence-based inferences. First, the duration of
the study was quite short, lasting only 4 weeks.
Thus, it is not clear whether results would have
changed had the intervention been carried out
over a longer time-frame. Second, the sample size
was small therefore reducing statistical power;
thus, this study would best be classified as pilot
work and further research is needed to clarify and
quantify findings. That said, given the difficulty
in recruiting highly trained competitive
bodybuilders to participate as subjects in an
experimental study, our findings nevertheless are
quite novel despite this limitation. Third, the
participants reported abstaining from anabolic
steroid usage for the last 3 months via a
questionnaire. However, we did not test for
anabolic agents and thus cannot rule out the
possibility that subjects were in fact using such
agents during the study period nor can we rule
out the possibility that previous use of
performance-enhancing drugs may have affected
results. Fourth, we did not monitor physical
activity levels outside the study protocol; thus,
any changes in physical activity, other than the
training program, or changes in sedentary
behavior may have confounded results. Fifth, we
did not assess participants’ eating habits prior to
the intervention; it is not known how previous
nutritional behaviors may have influenced the
observed findings. Finally, while the
anthropometric measures used to determine body
composition are important and viable tools in
practice, they lack the sensitivity to detect subtle
changes in body composition and did not allow
the ability to evaluate hypertrophic changes in
specific muscles.
Our results suggest that greater energy
intake in combination with regimented resistance
training induces greater increases in both muscle
mass and body fat in competitive male
The authors would like to express thanks to the bodybuilding athletes for their engagement in this
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Corresponding author:
João Pedro Nunes, BSc.
Metabolism, Nutrition and Exercise Laboratory.
Physical Education and Sport Center, Londrina State University.
Rodovia Celso Garcia Cid, km 380, Londrina, Brazil.
Phone: +5543999700301.
ORCID: 0000-0001-8144-5906.
... Energy deficit, through RT or caloric restriction, has been described to effectively decrease fat mass [51]. Although RT has been shown to maintain muscle mass and function [52], the addition of the supplements after a RT session has significantly reduced fat mass and increased muscle mass [53]. In effect, lower fat mass after RT and dietary supplementation with Cr, protein, or HMB-FA have been described [19,25,28,33,34]. ...
... In contrast to our results, previous investigations have reported superior benefits of a high-CHO diet compared to a low-CHO diet for changes in lean mass or measures of muscle hypertrophy. Ribeiro et al. (34) compared the effects of different amounts of energy intake with CHO surplus in eleven male bodybuilders. The results revealed that the group that ingested 12.9 g/kg/d of CHO achieved a greater increase in muscle mass than the group that ingested 8.0 g/kg/d (2.7% vs. 1.1%, respectively). ...
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This study's purpose was to compare the effects of different carbohydrate (CHO) intakes on body composition and muscular strength following eight weeks of resistance training (RT) in pre-conditioned men. In addition, we explored the individual responses to different CHO intakes. Twenty-nine young men volunteered to participate in this study. The participants were divided into two groups according to their relative CHO intake: lower (L-CHO; n = 14) and higher (H-CHO; n = 15). Participants performed a RT program four days a week for eight weeks. The lean soft tissue (LST) and fat mass were determined by dual-energy X-ray absorptiometry. Muscular strength was determined by a one-repetition maximum (1RM) test in the bench press, squat, and arm curl exercises. Both groups increased LST (P < 0.05) with no statistical differences between conditions (L-CHO = +0.8% vs. H-CHO = +3.5%). Neither group demonstrated changes in fat mass. Both groups increased 1RM (P < 0.05) in the bench press (L-CHO = +3.6% vs. H-CHO = +5.8%) and squat (L-CHO = +7.5% vs. H-CHO = +9.4%); however, only H-CHO significantly increased arm curl 1RM (P < 0.05) at post-training (L-CHO = +3.0% vs. H-CHO = +6.6%). Responsiveness was greater in H-CHO vs. L-CHO for LST and arm curl 1RM. In conclusion, lower and higher CHO intakes promote similar increase in LST and muscular strength; however, a greater intake may improve the responsiveness to gains in lean mass and arm curl strength in pre-conditioned men.
... Tanpa adanya Latihan beban yang terprogram, keseimbangan energi positif saja dapat meningkatkan massa bebas lemak asalkan asupan protein tercukupi. Selain itu pertumbuhan otot adalah proses yang tergantung pada ATP sehingga ketersediaan energi harus memadai untuk membentuk otot 34 . ...
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Latar Belakang: Perilaku self-made diet dan intensitas latihan yang tinggi pada anggota komunitas akan berdampak buruk bagi fungsi ginjal dan komposisi tubuh mereka. Tujuan: Menganalisis hubungan asupan makan dan intensitas latihan dengan fungsi ginjal dan komposisi tubuh pada komunitas gym. Metode: Penelitian ini merupakan penelitian cross-sectional yang dilakukan di beberapa pusat kebugaran di Kota Semarang dan melibatkan 54 pria anggota komunitas gym berusia 19-53 tahun. Data komposisi tubuh diperoleh menggunakan BIA. Kuesioner digunakan untuk memperoleh data intensitas latihan (durasi, frekuensi dan lama Latihan) sedangkan asupan makan menggunakan metode Semi Quantitative Food Frequency Questionnaire. Pemeriksaan kadar ureum menggunakan metode kalorimetri sedangkan kadar kreatinin menggunakan metode jaffe reaction. Analisis data menggunakan uji Rank-Spearman dan uji regresi linear berganda. Hasil: Mayoritas subjek memiliki frekuensi latihan sebanyak 5-7 kali dalam seminggu dengan rerata durasi 105,5±35,8 menit per kunjungan. Sebesar 85,2% subjek memiliki kadar ureum yang tinggi. Terdapat korelasi negatif antara asupan energi, protein, lemak dan durasi latihan dengan persen lemak tubuh. Semakin tinggi lama latihan dan semakin rendah asupan karbohirat maka massa otot dan tulang akan semakin meningkat. Peningkatan asupan protein dan lemak serta frekuensi latihan per pekan dapat meningkatkan kadar ureum dalam tubuh. Hasil uji multivariat menyatakan bahwa frekuensi latihan berpengaruh terhadap kadar ureum (21,5%) sedangkan durasi latihan memiliki pengaruh sebesar 9,7% terhadap persen lemak tubuh. Kesimpulan: Semakin lama frekuensi latihan per pekan maka semakin tinggi kadar ureum dalam darah dan semakin lama durasi latihan tiap kunjungan maka semakin rendah persen lemak tubuh.
... These objectives require the implementation of a diverse array of strategies to optimize physique aesthetics on show-day. Preparation for bodybuilding competition generally involves two phases: an off-season phase, in which the primary goal is to optimize muscle hypertrophy; and a pre-contest phase, in which the focus is to reduce subcutaneous body fat as low as possible while simultaneously maintaining muscle mass [1][2][3][4][5]. ...
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The present study analyzed the effects from day-before to day-of bodybuilding competition on intracellular water (ICW), extracellular water (ECW), total body water (TBW), and bioimpedance analysis (BIA) parameters (resistance, R; reactance, Xc; and derived scores) in bodybuilding athletes. We assessed anthropometry and BIA (foot-to-hand; tetrapolar; 50 kHz) in 11 male bodybuilders (29 ± 4 year-old; 81 ± 8 kg; 172 ± 7 cm; 27 ± 2 kg/m²) both one day pre-competition and on contest day. Results revealed significant increases in ICW (31.6 ± 2.9 to 33.1 ± 2.8 L), with concomitant decreases in ECW (19.8 ± 1.8 to 17.2 ± 1.4 L) and TBW (51.4 ± 4.6 to 50.3 ± 4.2 L) from day-before competition to contest day, which resulted in relatively large increases in the ICW/ECW ratio (1.60 ± 0.03 to 1.92 ± 0.01 L). Moreover, significant increases in R (391 ± 34 to 413 ± 33 ohm), Xc (64 ± 7 to 70 ± 6 ohm), and phase angle (9.3 ± 0.6 to 9.6 ± 0.7 degree) were observed between time periods. The phaseangle scores reported on show-day of 9.6 and 11.2 appear to be the highest group-mean and individual values observed in the literature to date. In conclusion, the strategies carried out on the final day of peak-week bodybuilding preparation lead to changes in BIA parameters and body water, with fluids shifting from the extra- to the intracellular compartment.
... It has been reported that a greater intake of energy with resistance training helps to increase muscle mass. 3 Several nutritional supplements are readily available in the market for improving muscle mass and exercise performance. Many people practice resistance exercise training with protein supplementation for improving muscle mass. ...
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Int J Cur Res Rev | Vol 13 • Issue 12 • June 2021150Efficacy and Safety of Creatine Supplementation on Strength and Muscle Mass in Resistance Trained Individuals: A Prospective StudyPriyanka Mirdha1, Vivek Nalgirkar2, Anant Patil3, Vijaykumar Gupta41Assistant Lecturer, Department of Physiology, Dr. DY Patil Medical College, Navi Mumbai, Maharashtra, India; 2Professor and Head, Depart-ment of Physiology, Dr. DY Patil Medical College, Navi Mumbai, Maharashtra, India; 3Assistant Professor, Department of Pharmacology, DY Patil University, School of medicine, Navi Mumbai, India; 4Assistant Professor, Department of Physiology, Dr. DY Patil Medical College, Navi Mumbai, Maharashtra, India.Corresponding Author:Dr. Priyanka Mirdha, Assistant Lecturer, Department of Physiology, Dr. DY Patil Medical College, Navi Mumbai, Maharashtra, India.Email: mirdha.priyanka@gmail.comISSN: 2231-2196 (Print) ISSN: 0975-5241 (Online)Received: 06.11.2020 Revised: 02.01.2021 Accepted: 18.02.2021 Published: 22.06.2021INTRODUCTIONWith the increasing number of cases of obesity and asso-ciated diseases, the importance of physical fitness is ever-growing.1 Several interventions including diet, exercise and its combination are being tried to reduce weight and improve physical fitness.2 With increased adaptation to automation and changes in lifestyle, physical fitness awareness among the public is becoming very important. Among adults and students, sports and exercise science is gaining popularity over the years. People are becoming interested in knowing how the body responds and adapts to exercise and strategies to improve performance for enjoying a longer and healthi (2) (PDF) Efficacy and Safety of Creatine Supplementation on Strength and Muscle Mass in Resistance Trained Individuals: A Prospective Study. Available from: [accessed Nov 26 2021].
... Interestingly, while both investigations confirmed a favorable influence of an energy surplus on FFM gains, this was not reflected in strength changes, perhaps because of the brief duration of training or due to nuances in the techniques used to assess strength and body composition. A recently published pilot study on male bodybuilders also supports the concept of greater body mass and muscle mass gains with a more aggressive energy intake (282 kJ·kg −1 ·day −1 ), although further inferences from this study are difficult due to methodological concerns (59). ...
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Resistance training is commonly prescribed to enhance strength/power qualities and is achieved via improved neuromuscular recruitment, fiber type transition, and/ or skeletal muscle hypertrophy. The rate and amount of muscle hypertrophy associated with resistance training is influenced by a wide array of variables including the training program, plus training experience, gender, genetic predisposition, and nutritional status of the individual. Various dietary interventions have been proposed to influence muscle hypertrophy, including manipulation of protein intake, specific supplement prescription, and creation of an energy surplus. While recent research has provided significant insight into optimization of dietary protein intake and application of evidence based supplements, the specific energy surplus required to facilitate muscle hypertrophy is unknown. However, there is clear evidence of an anabolic stimulus possible from an energy surplus, even independent of resistance training. Common textbook recommendations are often based solely on the assumed energy stored within the tissue being assimilated. Unfortunately, such guidance likely fails to account for other energetically expensive processes associated with muscle hypertrophy, the acute metabolic adjustments that occur in response to an energy surplus, or individual nuances like training experience and energy status of the individual. Given the ambiguous nature of these calculations, it is not surprising to see broad ranging guidance on energy needs. These estimates have never been validated in a resistance training population to confirm the “sweet spot” for an energy surplus that facilitates optimal rates of muscle gain relative to fat mass. This review not only addresses the influence of an energy surplus on resistance training outcomes, but also explores other pertinent issues, including “how much should energy intake be increased,” “where should this extra energy come from,” and “when should this extra energy be consumed.” Several gaps in the literature are identified, with the hope this will stimulate further research interest in this area. Having a broader appreciation of these issues will assist practitioners in the establishment of dietary strategies that facilitate resistance training adaptations while also addressing other important nutrition related issues such as optimization of fuelling and recovery goals. Practical issues like the management of satiety when attempting to increase energy intake are also addressed.
This review aimed to explore the nature of energy consumption for optimizing muscle growth in the presence of a resistance training program with a specific focus on implications for bodybuilders and physique athletes. Although gains in muscle mass can be achieved when resistance training is performed under hypocaloric conditions, research indicates that maximizing exercise-induced muscle hypertrophy requires an energy surplus. Herein, we discuss the interplay between total dietary energy intake and macronutrient ratios, and provide evidence-based guidelines as to how they should be manipulated to optimize muscular adaptations.
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Objective We performed a systematic review, meta-analysis and meta-regression to determine if dietary protein supplementation augments resistance exercise training (RET)-induced gains in muscle mass and strength. Data sources A systematic search of Medline, Embase, CINAHL and SportDiscus. Eligibility criteria Only randomised controlled trials with RET ≥6 weeks in duration and dietary protein supplementation. Design Random-effects meta-analyses and meta-regressions with four a priori determined covariates. Two-phase break point analysis was used to determine the relationship between total protein intake and changes in fat-free mass (FFM). Results Data from 49 studies with 1863 participants showed that dietary protein supplementation significantly (all p<0.05) increased changes (means (95% CI)) in: strength—one-repetition-maximum (2.49 kg (0.64, 4.33)), FFM (0.30 kg (0.09, 0.52)) and muscle size—muscle fibre cross-sectional area (CSA; 310 µm² (51, 570)) and mid-femur CSA (7.2 mm² (0.20, 14.30)) during periods of prolonged RET. The impact of protein supplementation on gains in FFM was reduced with increasing age (−0.01 kg (−0.02,–0.00), p=0.002) and was more effective in resistance-trained individuals (0.75 kg (0.09, 1.40), p=0.03). Protein supplementation beyond total protein intakes of 1.62 g/kg/day resulted in no further RET-induced gains in FFM. Summary/conclusion Dietary protein supplementation significantly enhanced changes in muscle strength and size during prolonged RET in healthy adults. Increasing age reduces and training experience increases the efficacy of protein supplementation during RET. With protein supplementation, protein intakes at amounts greater than ~1.6 g/kg/day do not further contribute RET-induced gains in FFM.
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Position statement The International Society of Sports Nutrition (ISSN) provides an objective and critical review related to the intake of protein for healthy, exercising individuals. Based on the current available literature, the position of the Society is as follows: 1) An acute exercise stimulus, particularly resistance exercise, and protein ingestion both stimulate muscle protein synthesis (MPS) and are synergistic when protein consumption occurs before or after resistance exercise. 2) For building muscle mass and for maintaining muscle mass through a positive muscle protein balance, an overall daily protein intake in the range of 1.4–2.0 g protein/kg body weight/day (g/kg/d) is sufficient for most exercising individuals, a value that falls in line within the Acceptable Macronutrient Distribution Range published by the Institute of Medicine for protein. 3) There is novel evidence that suggests higher protein intakes (>3.0 g/kg/d) may have positive effects on body composition in resistance-trained individuals (i.e., promote loss of fat mass). 4) Recommendations regarding the optimal protein intake per serving for athletes to maximize MPS are mixed and are dependent upon age and recent resistance exercise stimuli. General recommendations are 0.25 g of a high-quality protein per kg of body weight, or an absolute dose of 20–40 g. 5) Acute protein doses should strive to contain 700–3000 mg of leucine and/or a higher relative leucine content, in addition to a balanced array of the essential amino acids (EAAs). 6) These protein doses should ideally be evenly distributed, every 3–4 h, across the day. 7) The optimal time period during which to ingest protein is likely a matter of individual tolerance, since benefits are derived from pre- or post-workout ingestion; however, the anabolic effect of exercise is long-lasting (at least 24 h), but likely diminishes with increasing time post-exercise. 8) While it is possible for physically active individuals to obtain their daily protein requirements through the consumption of whole foods, supplementation is a practical way of ensuring intake of adequate protein quality and quantity, while minimizing caloric intake, particularly for athletes who typically complete high volumes of training. 9) Rapidly digested proteins that contain high proportions of essential amino acids (EAAs) and adequate leucine, are most effective in stimulating MPS. 10) Different types and quality of protein can affect amino acid bioavailability following protein supplementation. 11) Athletes should consider focusing on whole food sources of protein that contain all of the EAAs (i.e., it is the EAAs that are required to stimulate MPS). 12) Endurance athletes should focus on achieving adequate carbohydrate intake to promote optimal performance; the addition of protein may help to offset muscle damage and promote recovery. 13) Pre-sleep casein protein intake (30–40 g) provides increases in overnight MPS and metabolic rate without influencing lipolysis.
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Background: Despite a number of studies indicating increased dietary protein needs in bodybuilders with the use of the nitrogen balance technique, the Institute of Medicine (2005) has concluded, based in part on methodologic concerns, that “no additional dietary protein is suggested for healthy adults undertaking resistance or endurance exercise.” Objective: The aim of the study was to assess the dietary protein requirement of healthy young male bodybuilders ( with ≥3 y training experience) on a nontraining day by measuring the oxidation of ingested L-[1-¹³C]phenylalanine to ¹³CO2 in response to graded intakes of protein [indicator amino acid oxidation (IAAO) technique]. Methods: Eight men (means ± SDs: age, 22.5 ± 1.7 y; weight, 83.9 ± 11.6 kg; 13.0% ± 6.3% body fat) were studied at rest on a nontraining day, on several occasions (4–8 times) each with protein intakes ranging from 0.1 to 3.5 g · kg⁻¹ · d⁻¹, for a total of 42 experiments. The diets provided energy at 1.5 times each individual's measured resting energy expenditure and were isoenergetic across all treatments. Protein was fed as an amino acid mixture based on the protein pattern in egg, except for phenylalanine and tyrosine, which were maintained at constant amounts across all protein intakes. For 2 d before the study, all participants consumed 1.5 g protein · kg⁻¹ · d⁻¹. On the study day, the protein requirement was determined by identifying the breakpoint in the F¹³CO2 with graded amounts of dietary protein [mixed-effects change-point regression analysis of F¹³CO2 (labeled tracer oxidation in breath)]. Results: The Estimated Average Requirement (EAR) of protein and the upper 95% CI RDA for these young male bodybuilders were 1.7 and 2.2 g · kg⁻¹ · d⁻¹, respectively. Conclusion: These IAAO data suggest that the protein EAR and recommended intake for male bodybuilders at rest on a nontraining day exceed the current recommendations of the Institute of Medicine by ∼2.6-fold. This trial was registered at as NCT02621294.
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It is the position of the Academy of Nutrition and Dietetics (Academy), Dietitians of Canada (DC), and the American College of Sports Medicine (ACSM) that the performance of, and recovery from, sporting activities are enhanced by well-chosen nutrition strategies. These organizations provide guidelines for the appropriate type, amount, and timing of intake of food, fluids, and supplements to promote optimal health and performance across different scenarios of training and competitive sport. This position paper was prepared for members of the Academy, DC, and ACSM, other professional associations, government agencies, industry, and the public. It outlines the Academy’s, DC’s, and ACSM’s stance on nutrition factors that have been determined to influence athletic performance and emerging trends in the field of sports nutrition. Athletes should be referred to a registered dietitian nutritionist for a personalized nutrition plan. In the United States and in Canada, the Certified Specialist in Sports Dietetics is a registered dietitian nutritionist and a credentialed sports nutrition expert.
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Background: The consumption of a high protein diet (>4 g/kg/d) in trained men and women who did not alter their exercise program has been previously shown to have no significant effect on body composition. Thus, the purpose of this investigation was to determine if a high protein diet in conjunction with a periodized heavy resistance training program would affect indices of body composition, performance and health. Methods: Forty-eight healthy resistance-trained men and women completed this study (mean ± SD; Normal Protein group [NP n = 17, four female and 13 male]: 24.8 ± 6.9 yr; 174.0 ± 9.5 cm height; 74.7 ± 9.6 kg body weight; 2.4 ± 1.7 yr of training; High Protein group [HP n = 31, seven female and 24 male]: 22.9 ± 3.1 yr; 172.3 ± 7.7 cm; 74.3 ± 12.4 kg; 4.9 ± 4.1 yr of training). Moreover, all subjects participated in a split-routine, periodized heavy resistance-training program. Training and daily diet logs were kept by each subject. Subjects in the NP and HP groups were instructed to consume their baseline (~2 g/kg/d) and >3 g/kg/d of dietary protein, respectively. Results: Subjects in the NP and HP groups consumed 2.3 and 3.4 g/kg/day of dietary protein during the treatment period. The NP group consumed significantly (p < 0.05) more protein during the treatment period compared to their baseline intake. The HP group consumed more (p < 0.05) total energy and protein during the treatment period compared to their baseline intake. Furthermore, the HP group consumed significantly more (p < 0.05) total calories and protein compared to the NP group. There were significant time by group (p ≤ 0.05) changes in body weight (change: +1.3 ± 1.3 kg NP, -0.1 ± 2.5 HP), fat mass (change: -0.3 ± 2.2 kg NP, -1.7 ± 2.3 HP), and % body fat (change: -0.7 ± 2.8 NP, -2.4 ± 2.9 HP). The NP group gained significantly more body weight than the HP group; however, the HP group experienced a greater decrease in fat mass and % body fat. There was a significant time effect for FFM; however, there was a non-significant time by group effect for FFM (change: +1.5 ± 1.8 NP, +1.5 ± 2.2 HP). Furthermore, a significant time effect (p ≤ 0.05) was seen in both groups vis a vis improvements in maximal strength (i.e., 1-RM squat and bench) vertical jump and pull-ups; however, there were no significant time by group effects (p ≥ 0.05) for all exercise performance measures. Additionally, there were no changes in any of the blood parameters (i.e., basic metabolic panel). Conclusion: Consuming a high protein diet (3.4 g/kg/d) in conjunction with a heavy resistance-training program may confer benefits with regards to body composition. Furthermore, there is no evidence that consuming a high protein diet has any deleterious effects.
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Competitive bodybuilders are well known for extreme physique traits and extremes in diet and training manipulation to optimize lean mass and achieve a low body fat. Although many of the dietary dogmas in bodybuilding lack scientific scrutiny, a number, including timing and dosing of high biological value proteins across the day, have more recently been confirmed as effective by empirical research studies. A more comprehensive understanding of the dietary intakes of bodybuilders has the potential to uncover other dietary approaches, deserving of scientific investigation, with application to the wider sporting, and potential health contexts, where manipulation of physique traits is desired. Our objective was to conduct a systematic review of dietary intake practices of competitive bodybuilders, evaluate the quality and currency of the existing literature, and identify research gaps to inform future studies. A systematic search of electronic databases was conducted from the earliest record until March 2014. The search combined permutations of the terms 'bodybuilding', 'dietary intake', and 'dietary supplement'. Included studies needed to report quantitative data (energy and macronutrients at a minimum) on habitual dietary intake of competitive bodybuilders. The 18 manuscripts meeting eligibility criteria reported on 385 participants (n = 62 women). Most studies were published in the 1980-1990s, with three published in the past 5 years. Study methodological quality was evaluated as poor. Energy intake ranged from 10 to 24 MJ/day for men and from 4 to 14 MJ/day for women. Protein intake ranged from 1.9 to 4.3 g/kg for men and from 0.8 to 2.8 g/kg for women. Intake of carbohydrate and fat was <6 g/kg/day and below 30 % of energy, respectively. Carbohydrate intakes were below, and protein (in men) intakes were higher than, the current recommendations for strength athletes, with no consideration for exploration of macronutrient quality or distribution over the day. Energy intakes varied over different phases of preparation, typically being highest in the non-competition (>6 months from competition) or immediate post-competition period and lowest during competition preparation (≤6 months from competition) or competition week. The most commonly reported dietary supplements were protein powders/liquids and amino acids. The studies failed to provide details on rationale for different dietary intakes. The contribution of diet supplements was also often not reported. When supplements were reported, intakes of some micronutrients were excessive (~1000 % of US Recommended Dietary Allowance) and above the tolerable upper limit. This review demonstrates that literature describing the dietary intake practices of competitive bodybuilders is dated and often of poor quality. Intake reporting required better specificity and details of the rationale underpinning the use. The review suggests that high-quality contemporary research is needed in this area, with the potential to uncover dietary strategies worthy of scientific exploration.
Skeletal muscle proteolysis is highly regulated, involving complex intramuscular proteolytic systems that recognize and degrade muscle proteins, and recycle free amino acid precursors for protein synthesis and energy production. Autophagy-lysosomal, calpain, and caspase systems are contributors to muscle proteolysis, although the ubiquitin proteasome system (UPS) is the primary mechanism by which actomyosin fragments are degraded in healthy muscle. The UPS is sensitive to mechanical force and nutritional deprivation, as recent reports have demonstrated increased proteolytic gene expression and activity of the UPS in response to resistance and endurance exercise, and short-term negative energy balance. However, consuming dietary protein alone (or free amino acids), or as a primary component of a mixed meal, may attenuate intramuscular protein loss by down-regulating proteolytic gene expression and the catabolic activity of the UPS. Although these studies provide novel insight regarding the intramuscular regulation of skeletal muscle mass, the role of proteolysis in the regulation of skeletal muscle protein turnover in healthy human muscle is not well described. This article provides a contemporary review of the intramuscular regulation of skeletal muscle proteolysis in healthy muscle, methodological approaches to assess proteolysis, and highlights the effects of nutrition and exercise on skeletal muscle proteolysis. © 2014 IUBMB Life, 2014
Biopsies (biceps) were examined in 8 bodybuilders across a typical arm-curl training session (80% 1-RM). [PCr] and [glycogen] decreased 62 and 12% after 1 set (n = 4), and 50 and 24% after 3 sets (n = 4). [Lactate] was 91 and 118 mmol &times kg-1, respectively, after 1 and 3 sets. Fatigue was probably partially caused by decreased [PCr] and increased [H+] (first set) and by decreased [H+] in subsequent sets.
Abstract Strength training and positive energy intake are the most important factors related to lean body mass (LBM) gain. Most studies investigating weight-gain interventions are based recreationally active subjects and less is known about optimal weight-gain protocols in elite athletes. The purpose of this study was to evaluate the effect of nutritional guidance in an 8- to 12-week weight-gain period in elite athletes. Thirty-nine elite athletes were randomised to either a 'nutritional counseling group' (NCG, n=21, 19.1±2.9 years, 70.9±8.9 kg) or 'ad libitum group' (ALG, n=18, 19.6±2.7 years, 75.0±5.9 kg). All athletes continued their sport-specific training which included an additional four strength-training sessions per week. NCG followed a meal plan providing a positive energy balance, while the ALG athletes had an ad libitum energy intake. Body weight (BW), body composition, one repetition maximum (1RM), 40 m sprint and counter movement jump (CMJ) were measured pre- and post-intervention. Energy intake was higher in the NCG than in the ALG (3585±601 vs. 2964±884 kcal) and consequently BW increased more in NCG than in ALG (3.9±0.6% vs. 1.5±0.4%). Fat mass (FM) increased more in NCG than in ALG (15±4 vs. 3±3%), but gain in LBM was not different between groups. All 1RM results improved in both groups (6-12%), whereas 40 m sprint and CMJ remained unchanged, except for a significant decrease in 40 m sprint for the athletes in NCG. Athletes with nutritional guidance increased BW more, however, excess energy intake in a weight-gain protocol should be considered carefully due to undesirable increases in body fat.