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The Influence of the Aerobic Training on Muscle Hypertrophy: Literature Review

Authors:

Abstract

The literature presents some studies that show that aerobic exercise is responsible for mediating muscle catabolism. Thus, it is interpreted that continuous aerobic exercise produces little or no increase in muscle hypertrophy. The purpose of this review was to demonstrate the effects of aerobic training on muscle hypertrophy alone or in conjunction with resistance training. The present study is characterized by a review of the narrative literature, the databases of SciELO, Google academic and PubMed were consulted. Many studies show that aerobic training (AT) can promote hypertrophic responses in untrained individuals, however, these responses are related to exercise variables such as intensity, volume, frequency, and modality. Higher, continuous or interval intensities, at least 80% of the HRR, seem to be capable of promoting hypertrophic responses when compared to low intensities. In addition, the training volume may also influence this response and different modalities may have a distinct response to muscle hypertrophy. While the combination of TA and resistance training (TR) corresponds to concurrent training (CT), the literature demonstrates that AT in CT can negatively affect acute and chronic hypertrophic responses depending on intensity, volume, mode and training schedule. Keywords: Exercise. Physical Education and Training. Metabolism. ResumoA literatura apresenta alguns estudos que mostram que exercício aeróbio é responsável por mediar o catabolismo muscular. Dessa maneira, interpreta-se que o exercício contínuo aeróbio produz pouco ou nenhum aumento na hipertrofia muscular. O objetivo desta revisão foi demonstrar os efeitos do treinamento aeróbio sobre a hipertrofia muscular de forma isolada ou em conjunto com o treinamento resistido. O presente estudo caracteriza-se um delineamento de revisão de literatura narrativa, foram consultadas as bases de dados do SciELO, Google acadêmico e PubMed. Muitos estudos mostram que o treinamento aeróbio (TA) pode promover respostas hipertróficas em indivíduos não treinados, entretanto, estas respostas estão relacionadas às variáveis do exercícios como intensidade, volume, frequência e modalidade. Intensidades mais altas, contínuas ou intervaladas, no mínimo 80% da FCR, parecem ser capazes de promover respostas hipertróficas quando comparado a baixas intensidades. Além disso, o volume do treinamento também pode influenciar esta resposta e diferentes modalidades podem ter resposta distinta sobre a hipertrofia muscular. Enquanto a combinação do TA com o treinamento resistido (TR) corresponde ao treinamento concorrente (TC), a literatura demonstra que o TA no TC pode interferir negativamente nas respostas hipertróficas de maneira aguda e crônica dependendo da intensidade, volume, modalidade e programação de treinamento. Palavras-chave: Exercício. Educação Física e Treinamento. Metabolismo.
The Inuence of the Aerobic Training on Muscle Hypertrophy: Literature Review
382
J Health Sci 2019;21(4):382-5
Anderson Geremias Macedo*a; David Michel de Oliveirab
Abstract
The literature presents some studies that show that aerobic exercise is responsible for mediating muscle catabolism. Thus, it is interpreted that
continuous aerobic exercise produces little or no increase in muscle hypertrophy. The purpose of this review was to demonstrate the eects of
aerobic training on muscle hypertrophy alone or in conjunction with resistance training. The present study is characterized by a review of the
narrative literature, the databases of SciELO, Google academic and PubMed were consulted. Many studies show that aerobic training (AT) can
promote hypertrophic responses in untrained individuals, however, these responses are related to exercise variables such as intensity, volume,
frequency, and modality. Higher, continuous or interval intensities, at least 80% of the HRR, seem to be capable of promoting hypertrophic
responses when compared to low intensities. In addition, the training volume may also inuence this response and dierent modalities may
have a distinct response to muscle hypertrophy. While the combination of TA and resistance training (TR) corresponds to concurrent training
(CT), the literature demonstrates that AT in CT can negatively aect acute and chronic hypertrophic responses depending on intensity, volume,
mode and training schedule.
Keywords: Exercise. Physical Education and Training. Metabolism.
Resumo
A literatura apresenta alguns estudos que mostram que exercício aeróbio é responsável por mediar o catabolismo muscular. Dessa maneira,
interpreta-se que o exercício contínuo aeróbio produz pouco ou nenhum aumento na hipertroa muscular. O objetivo desta revisão foi
demonstrar os efeitos do treinamento aeróbio sobre a hipertroa muscular de forma isolada ou em conjunto com o treinamento resistido. O
presente estudo caracteriza-se um delineamento de revisão de literatura narrativa, foram consultadas as bases de dados do SciELO, Google
acadêmico e PubMed. Muitos estudos mostram que o treinamento aeróbio (TA) pode promover respostas hipertrócas em indivíduos não
treinados, entretanto, estas respostas estão relacionadas às variáveis do exercícios como intensidade, volume, frequência e modalidade.
Intensidades mais altas, contínuas ou intervaladas, no mínimo 80% da FCR, parecem ser capazes de promover respostas hipertrócas quando
comparado a baixas intensidades. Além disso, o volume do treinamento também pode inuenciar esta resposta e diferentes modalidades podem
ter resposta distinta sobre a hipertroa muscular. Enquanto a combinação do TA com o treinamento resistido (TR) corresponde ao treinamento
concorrente (TC), a literatura demonstra que o TA no TC pode interferir negativamente nas respostas hipertrócas de maneira aguda e crônica
dependendo da intensidade, volume, modalidade e programação de treinamento.
Palavras-chave: Exercício. Educação Física e Treinamento. Metabolismo.
The Inuence of the Aerobic Training on Muscle Hypertrophy: Literature Review
A Inuência do Treinamento Aeróbio Sobre a Hipertroa Muscular: Revisão de Literatura
DOI: http://dx.doi.org/10.17921/2447-8938.2019v21n4p382-5
aAnhanguera University, Physical Education Course. SP, Brazil.
bFederal University of Goiás, Department of Physical Education/ Special Unit of Sciences. GO, Brazil.
*E-mail: andersongmacedo@yahoo.com.br
Recebido em: 22/04/2019; Aprovado em: 02/07/2019
1 Introduction
In literature it is not clear the role of aerobic training
(TA) on the muscle hypertrophy yet. Some evidences in
the literature show that aerobic exercise is responsible for
mediating muscle catabolism.1 Atherton et al.2 led a pioneering
study that explained the dierences in the responses of the
intracellular signaling between two types of exercises. Using
an animal model, the isolated plantar exor muscle of rats was
stimulated in two ways, with high frequency intermittently,
simulating the stimulus of the resistive exercise or low
frequency continuously simulating continuous exercise. The
analyzes after the intervention showed that the low frequency
stimulation increased the phosphorylation of activated protein
kinase (AMPK by adenosine monophosphate ) and high
frequency stimulation reduced the phosphorylation of this
protein. However, the phosphorylation of threonine\serotonin
tyrosine kinase (AKT) protein increased with the stimulus of
high frequency and reduced by stimulation of low frequency.
Thus, it seems that the intracellular responses via AMPK or
AKT may be mediated by the type of exercise. In addition,
the opposite intracellular signaling can reduce the adaptive
responses of skeletal muscle through the interaction between
these two proteins2.
However, some studies demonstrate that the TA alone
can promote the hypertrophy by increasing the activation
of rapamycin (mTOR) a protein important in the process of
intracellular signaling in the anabolism process3,4. On the other
hand, the TA when performed together with resistance training
(RT) seems to compromise the hypertrophic adaptations
383
J Health Sci 2019;21(4):382-5
Macedo, AG; Oliveira, DM
promoted by the TR5.6.
The purpose of this review was to demonstrate the
eects of aerobic training on muscle hypertrophy alone or in
conjunction with resistance training.
2 Development
This study aims to outline the literature of review narrative.
Books were analyzed regarding the theme and international
scientic articles found in the Scielo databases, Google Scholar
and PubMed. The following words were used in the Virtual
Health Library (VHL) in Portuguese: “hipertroa muscular”,
“treinamento aeróbio”, “treinamento resistido”, “treinamento
concorrente” and English: “hypertrophic muscle”, “ aerobic
training”, “ resistance training”, “concurrent training”. For
the inclusion criterion an analysis was used by checking the
studies that showed a relation with the theme of this study.
2.1 Discussion
2.1.1 Eects of aerobic exercise on the hypertrophy
Some studies in the literature show that TA can promote
hypertrophic responses in untrained individuals . With 12
weeks of TA it was able to promote increases in skeletal muscle
mass in men and untrained women 7. This answer seems to be
mediated by increased anabolic mediated by insulin signaling;
increase in the transport of amino acids; increased blood ow
and perfusion in skeletal muscle; reduction of the catabolic
signaling proteins as myostatin; increase in the number and
size of the mitochondria1,6,7. However some training variables
should be analyzed in adapting cardiomyopathy induced by
TA such as intensity, volume, frequency and type1.
Some studies in the literature indicate that higher
intensities are necessary for achieving signicant muscle
growth through the TA1.3. Trape et al.8 observed a decrease
in the cross-sectional area (AST) of approximately 20%
in the bers of type I and II after 13 weeks of TA with low
intensity for marathon race. This shows that the TA with this
intensity is not benecial to hypertrophy. In spite of not being
established in the literature which specic intensity that the
TA promotes hypertrophy, it is suggested that the minimum
intensity of 80% of heart rate reserve (HRR) being continuous
or intervals seems to promote the best hypertrophic gains
induced by TA. The high intensity interval training increased
AST at around 24% in middle-aged individuals with diabetes
type 2, indicating a relation between the intensity of TA and
muscular hypertrophy6.
The impact of the volume may be dependent on the
frequency. Scharwts et al.9 compared changes in body
composition in young men and elderly patients after 6
months of the TA protocol. The results showed an increase
in muscle mass only in elderly men with no change in young
men. However, the authors emphasized that adherence to the
training protocol was higher for elderly individuals, this way
the hypertrophic benets found in this population are involved
directly by the training frequency.
In relation to the hypertrophic responses mediated by
dierent modalities of TA, they are still not clear. Some
studies involving this theme has used the cycling and have
demonstrated increased muscle growth1. Whereas Schwartz
et al.9 found an increase in muscle mass only in elderly
individuals after 6 months of training protocol involving the
modalities of walking and running. On the other hand, Sipila
and Suominen10 showed that elderly women who underwent
combination of step and race with intensities above 80% of
the FCR did not show signicant increases after 18 weeks of
training. Agreeing with these ndings, Jubrias et al.11 showed
that the AST of elderly men and women did not suer changes
after 24 weeks involving climbing and rowing exercises types
being that the training protocol consisted of progressive
increase to up to 85% FCR. Thus, the hypertrophic response
induced by other forms of aerobic exercise with the exception
of cycling still require further investigation.
2.1.2 Eects of isolated continuous aerobic exercise on the
hypertrophy
TA is often combined with the TR to accelerate the
reduction of body weight, improvement in sports performance,
or both. This strategy is called concurrent training (CT), this
type of training has demonstrated positive eects on body
weight maintenance12. However, some evidences show that in
TR programs, TA can inuence or even aect muscle growth.
The negative eects of TC on the hypertrophy is known as
chronic interference. The hypothesis of this interference
seems to occur by the fact that skeletal muscle is unable to
maximize its = morphological and metabolic adaptations
to TR or TA5. Similar to the hypothesis of interaction of
AMPK-Akt, chronic interference of both training seems to
promote competitive adjustments that produce dierences in
intracellular responses reducing the hypertrophic gains.
Despite the logical foundations of the hypothesis of the
interferences of TA in hypertrophic gains induced by RT, these
eects are not well understood in humans yet. Some studies
have shown that the combination of TA and TR prevents the
anabolic signaling induced by RT13,14, others seem that the TA
does not aect this signs15. However, the acute eect of TC
does not seem to aect the muscle proteins synthesis 16,17.
Although the TA does not aect acutely the synthesis of
proteins induced by RT, chronically TA seems to negatively
aect muscle growth. Acutely TA can interfere with the TR
ability, which can cause fatigue, through the increase of local
metabolites and/or depletion of substrate, compromising the
TR quality17. So, the muscle adaptations are harmed by the
reduction of capacity, intensity and reduction in the volume
of the session of the TR these being important factors in the
process of stimulus to the myobrillar growth6. Another
potential mechanism of TC which can compromise the
hypertrophic process is overtraining. Because when the
The Inuence of the Aerobic Training on Muscle Hypertrophy: Literature Review
384
J Health Sci 2019;21(4):382-5
volume or intensity of training exceeds the capacity of the
body recovery the anabolic process is compromised. In
addition, stress added by TA can promote an increase of
catabolic hormones6.
Studies that investigated the results of TC in a chronic
form on the muscle adaptations showed that the TA seems
to aect the muscle growth. The meta-analysis by Wilson
et al.5 showing the size of the eects for muscle growth was
reduced by around 50% in weight lifters when the TA was
added to RT. Kraemer et al.18 showed that after 12 weeks of
training, the TR group presented an increase in the AST of
the bers type II, IIa and IIc, whereas the CT group there was
only an increase of AST of type IIa bers. Agreeing with these
ndings Bell et al.19 found similar results with active students,
after 12 weeks of TA in the stationary bicycle, TR and TC.
The TR group presented an increase in the AST of bers of
type I and II, but the TC increase occurred only in the bers
of type II. However, there are several factors by which the TA
can inuence the muscle adaptations associated with the RT.
In particular, the variables of the TA such as intensity, volume
and frequency, modality and programming are fundamental
in this answer.
Some evidences suggest that the model called sprint
interval training of high intensity is more harmful to the
intracellular anabolic ags that the model moderate intensity
continuous training19. Apparently due to the great interference
associated to high intensity training, it seems that TA with
lower intensities is more indicated to maximize muscle
hypertrophy during TC. However, the results and conclusions
of these studies were through acute responses of TC.
The volume can have a big impact on hypertrophic
interference associated with TC, potentially related to
the symptoms induced by overtraining through muscle
catabolism induced by the hormonal system and glycogen
depletion20. Wilson et al.5 revealed a statistically signicant
negative correlation between muscle hypertrophy and volume
(duration and frequency) of TA during TC, specically the
duration presents a strong inverse correlation with muscle
hypertrophy.
But the frequency variations of TA may also inuence the
responses of TC. Jones et al.21 demonstrated that individuals
have gone through a protocol of RT for 3 days per week and
TA were added to this Protocol. The results showed that the
circumference of the quadriceps was greater for the protocol
that performed only TR (+4.3%) for the groups that underwent
1 and 3 days of TA, there was an increase (+2.8% and 1%,
respectively). These results indicate that the frequency of TA
can decrease the muscle hypertrophy in TC.
Among the modalities of TA, the most studied ones
are running and cycling. The meta-analysis by Wilson et
al.5 revealed that running has particular negative eect on
hypertrophic adaptation associated with TR, while cycling
seems not to harm the hypertrophic response. In contrast,
Panissa et al.22 demonstrated that training with high intensity
cycling promotes greater harm to strength gains compared to
running high intensity before starting the RT.
Depending on the purpose of the training program, the TA
can be done in the same session of TR or on alternate days.
Some studies have assessed whether the order of TA and TR
in the same session of TC may aect intracellular responses.
Coey et al.13 investigated the acute eects of a combined
training session involving the knee extension and cycling
with moderate intensities. Biking performed before exercise
resulted in the increase of Akt but a reduction of IGF1 mRNA,
in opposite sequence there was an increase in the IGF1 mRNA
and increased IGF1 mRNA. On the chronic eect of exercise
order of TC in the same session show that the gains of forces
are similar regardless of the order23.24. Therefore, it seems that
the mechanical tension seems not to be aected by order of
TA and TR in the same session of TC. Cadore et al.25found
similar results of muscle diameter increases regardless if the
TA or TR was done rst in the TC session. Similarly, Davit et
al.26 observed that the changes in the body composition were
not aected by the TA performed before or after the TR. These
studies seem not clarify safely yet on the importance of the
sequence of TA and TR in TC on the muscle hypertrophy. The
literature has pointed out that the recovery period between the
TA and TR of few hours or alternate days seems to minimize
the eects on hypertrophic adaptation5. Although the sequence
of TA seems to interfere in the hypertrophic response, studies
involving this issue are still scarce in the literature.
3 Conclusion
Unlike the thought of a large majority of the professionals
of physical education, TA can promote muscle hypertrophy in
sedentary subjects, being these gains especially in the bers
of type I. However, some factors such as intensity, volume,
frequency and modality may inuence this response. Training
with intensity above 80% of HR seems to promote greater
gains in muscle mass. TC may interfere in the hypertrophic
adaptations, particularly the TA with high volume seems to
impair the hypertrophy. The negative eects of TC can be
minimized if the recovery between TA and TR is a few hours
or alternate days.
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