scholarly journals Resistance training and timed essential amino acids protect against the loss of muscle mass and strength during 28 days of bed rest and energy deficit

2008 ◽  
Vol 105 (1) ◽  
pp. 241-248 ◽  
Author(s):  
Naomi Brooks ◽  
Gregory J. Cloutier ◽  
Samuel M. Cadena ◽  
Jennifer E. Layne ◽  
Carol A. Nelsen ◽  
...  

Spaceflight and bed rest (BR) result in losses of muscle mass and strength. Resistance training (RT) and amino acid (AA) supplementation are potential countermeasures to minimize these losses. However, it is unknown if timing of supplementation with exercise can optimize benefits, particularly with energy deficit. We examined the effect of these countermeasures on body composition, strength, and insulin levels in 31 men (ages 31–55 yr) during BR (28 days) followed by active recovery (14 days). Subjects were randomly assigned to essential AA supplementation (AA group, n = 7); RT with AA given 3 h after training (RT group, n = 12); or RT with AA given 5 min before training (AART group, n = 12). Energy intake was reduced by 8 ± 6%. Midthigh muscle area declined with BR for the AA > RT > AART groups: −11%, −3%, −4% ( P = 0.05). Similarly, greatest losses in lower body muscle strength were seen in the AA group (−22%). These were attenuated in the exercising groups [RT (−8%) and AART (−6%; P < 0.05)]. Fat mass and midthigh intramuscular fat increased after BR in the AA group (+3% and +14%, respectively), and decreased in the RT (−5% and −4%) and AART groups (−1 and −5%; P = 0.05). Muscle mass and strength returned toward baseline after recovery, but the AA group showed the lowest regains. Combined resistance training with AA supplementation pre- or postexercise attenuated the losses in muscle mass and strength by approximately two-thirds compared with AA supplement alone during BR and energy deficit. These data support the efficacy of combined AA and RT as a countermeasure against muscle wasting due to low gravity.

2021 ◽  
Vol 3 (2) ◽  
pp. 60
Author(s):  
Gutama Arya Pringga ◽  
R. A. Meisy Andriana ◽  
Indrayuni Lukitra Wardhani ◽  
Lydia Arfianti

Background: Resistance training is an effective way to increase muscle mass. Resistance training with agonist-antagonist paired set method can be an alternative to increase muscle mass within a relatively short training time.Aim: To compare the increase in hamstrings and quadriceps femoris muscle thickness between agonist-antagonist paired set (APS) and traditional set (TS) resistance training in untrained healthy subjects.Material and Methods: This study was an experimental study on 16 untrained healthy men which were randomly assigned to the APS and the TS group. Each group got leg curl and leg extension exercises with equal training volume for 6 weeks. For the APS group, 1 set of leg curls was followed by 1 set of leg extensions, repeated for 3 sets. For the TS group, 3 sets of leg curls were followed by 3 sets of leg extensions. Muscle thickness was compared from pre- to post-training and between the intervention groups using B-mode ultrasound.Results: Muscle thickness of the hamstrings and quadriceps femoris increased significantly from pre- to post-training in both groups (p<0.05). The increase in muscle thickness between the two groups was not significantly different (p> 0.05).Conclusion: Resistance training with the APS method did not give a higher increment of hamstrings and quadriceps femoris muscle thickness compared to the TS method in healthy untrained subjects.


2013 ◽  
Vol 114 (9) ◽  
pp. 1253-1262 ◽  
Author(s):  
A. H. V. Remels ◽  
H. R. Gosker ◽  
R. C. J. Langen ◽  
A. M. W. J. Schols

Pulmonary cachexia is a prevalent, debilitating, and well-recognized feature of COPD associated with increased mortality and loss of peripheral and respiratory muscle function. The exact cause and underlying mechanisms of cachexia in COPD are still poorly understood. Increasing evidence, however, shows that pathological changes in intracellular mechanisms of muscle mass maintenance (i.e., protein turnover and myonuclear turnover) are likely involved. Potential factors triggering alterations in these mechanisms in COPD include oxidative stress, myostatin, and inflammation. In addition to muscle wasting, peripheral muscle in COPD is characterized by a fiber-type shift toward a more type II, glycolytic phenotype and an impaired oxidative capacity (collectively referred to as an impaired oxidative phenotype). Atrophied diaphragm muscle in COPD, however, displays an enhanced oxidative phenotype. Interestingly, intrinsic abnormalities in (lower limb) peripheral muscle seem more pronounced in either cachectic patients or weight loss-susceptible emphysema patients, suggesting that muscle wasting and intrinsic changes in peripheral muscle's oxidative phenotype are somehow intertwined. In this manuscript, we will review alterations in mechanisms of muscle mass maintenance in COPD and discuss the involvement of oxidative stress, inflammation, and myostatin as potential triggers of cachexia. Moreover, we postulate that an impaired muscle oxidative phenotype in COPD can accelerate the process of cachexia, as it renders muscle in COPD less energy efficient, thereby contributing to an energy deficit and weight loss when not dietary compensated. Furthermore, loss of peripheral muscle oxidative phenotype may increase the muscle's susceptibility to inflammation- and oxidative stress-induced muscle damage and wasting.


Nutrients ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 3083
Author(s):  
Pedro L. Valenzuela ◽  
Adrián Castillo-García ◽  
Alejandro Lucia ◽  
Fernando Naclerio

Ketogenic diets (KD) have gained popularity in recent years among strength-trained individuals. The present review summarizes current evidence—with a particular focus on randomized controlled trials—on the effects of KD on body composition and muscle performance (strength and power output) in strength-trained individuals. Although long-term studies (>12 weeks) are lacking, growing evidence supports the effectiveness of an ad libitum and energy-balanced KD for reducing total body and fat mass, at least in the short term. However, no or negligible benefits on body composition have been observed when comparing hypocaloric KD with conventional diets resulting in the same energy deficit. Moreover, some studies suggest that KD might impair resistance training-induced muscle hypertrophy, sometimes with concomitant decrements in muscle performance, at least when expressed in absolute units and not relative to total body mass (e.g., one-repetition maximum). KD might therefore be a beneficial strategy for promoting fat loss, although it might not be a recommendable option to gain muscle mass and strength/power. More research is needed on the adoption of strategies for avoiding the potentially detrimental effect of KD on muscle mass and strength/power (e.g., increasing protein intake, reintroduction of carbohydrates before competition). In summary, evidence is as yet scarce to support a major beneficial effect of KD on body composition or performance in strength-trained individuals. Furthermore, the long-term effectiveness and safety of this type of diet remains to be determined.


2021 ◽  
pp. 1-16
Author(s):  
Majid Mufaqam Syed-Abdul ◽  
Chrissa L. McClellan ◽  
Elizabeth J. Parks ◽  
Stephen D. Ball

Abstract Ageing is associated with reduced muscle mass, strength, flexibility and balance, resulting in a poor quality of life (QOL). Past studies have occurred in highly controlled laboratory settings which provide strong support to determine whether similar gains can be made in community programmes. Twenty participants were enrolled in an eight-week community-based resistance training programme (mean age = 61.3 (standard error (SE) = 0.9) years); Body Mass Index = 32.0 (SE = 1.3) kg/m2). All participants completed surveys to assess outcomes associated with QOL. Given the relationship between muscle function and nerve health, nerve conduction studies (NCS) were also conducted in a separate group of participants (mean age = 64.9 (SE = 2.0) years; Body Mass Index = 32.6 (SE = 1.9) kg/m2). This community-based training programme significantly improved QOL measures in older adults (p < 0.001). Although weight loss was not the primary outcome of the study, participants reduced their body weights (p < 0.001), by primarily reducing fat mass (p = 0.007) while maintaining muscle mass. Significant improvements were observed in muscle strength (2.2%), flexibility and balance (3.2–464.2%, p ⩽ 0.05 for all). Improvements were also observed in plasma glucose (p = 0.05), haemoglobin A1C (p = 0.06) and aldolase enzyme levels (p < 0.001). Scores for surveys on memory and sleep improved (p < 0.05). Improved QOL was associated with increased lean mass (r = −0.714, p = 0.002), decreased fat mass (r = −0.702, p = 0.003) and improved flexibility and balance (r = −0.627, p = 0.008). An eight-week, community-based resistance training programme significantly improved QOL in older adults. Influence on the lipid profile and NCS still needs further investigation.


2021 ◽  
Author(s):  
Isabela Nogueira Martins Sena Rios ◽  
Fernando Lamarca ◽  
Flávio Teixeira Vieira ◽  
Heloísa Antoniella Braz de Melo ◽  
Kelly Grace Magalhães ◽  
...  

Antioxidants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 588
Author(s):  
Hayden W. Hyatt ◽  
Scott K. Powers

Skeletal muscle is the most abundant tissue in the body and is required for numerous vital functions, including breathing and locomotion. Notably, deterioration of skeletal muscle mass is also highly correlated to mortality in patients suffering from chronic diseases (e.g., cancer). Numerous conditions can promote skeletal muscle wasting, including several chronic diseases, cancer chemotherapy, aging, and prolonged inactivity. Although the mechanisms responsible for this loss of muscle mass is multifactorial, mitochondrial dysfunction is predicted to be a major contributor to muscle wasting in various conditions. This systematic review will highlight the biochemical pathways that have been shown to link mitochondrial dysfunction to skeletal muscle wasting. Importantly, we will discuss the experimental evidence that connects mitochondrial dysfunction to muscle wasting in specific diseases (i.e., cancer and sepsis), aging, cancer chemotherapy, and prolonged muscle inactivity (e.g., limb immobilization). Finally, in hopes of stimulating future research, we conclude with a discussion of important future directions for research in the field of muscle wasting.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1757.2-1757
Author(s):  
T. Raskina ◽  
I. Grigoreva ◽  
J. Averkieva ◽  
A. Kokov ◽  
V. Masenko

Objectives:To examine bone mineral density (BMD) in men with coronary heart disease (CHD), depending on the state of the muscle mass, strength and function.Methods:79 men aged over 50 years with verified CHD were examined (mean age 63 (57; 66) years).The BMD and T-criterion (standart deviation, SD) of the femoral neck and lumbar spine (L1-L4) were evaluated using dual-energy x-ray absorptiometry (DXA) on the Lunar Prodigy Primo bone densitometer (USA). The following reference intervals were used: normal BMD values (T-criterion ≥-1), osteopenia (OPe) (T-criterion from -1 to -2.5), and osteoporosis (OP) (T-criterion <-2.5).To assess muscle mass, the total area (cm2) of the lumbar muscles of the axial section at the level of the 3rd lumbar vertebra (L3) was determined using multispiral computed tomography on a 64-slice computer tomograph “Somatom Sensation 64” (Siemens AG Medical Solution, Germany). The ratio of the obtained index of the area of skeletal muscle to the square of the patient’s growth index determined the “ skeletalmuscular index L3” (SMI). The media considered the threshold value to be 52.4 cm2/m2.Results:The femoral neck BMD in the examined patients was 0.96 (0.89; 1.03) g/cm2, which corresponds to -0.50 (-1.00; 0) SD according to the T-criterion, in the lumbar spine -1.23 (1.11; 1.32) g/cm2and 0.4 (-0.50; 1.20) SD according to the T-criterion.In accordance with the recommendations of the European working group on sarcopenia in Older people (EWGSOP, 2010, 2018), the patients were divided into 3 groups: 31 patients without sarcopenia (group 1), 21 patients with isolated muscle loss (presarcopenia) (group 2) and 27 patients with sarcopenia (group 3).BMD in the femoral neck in the group of patients without sarcopenia was 0.96 (0.72; 1.26) g/cm2, which corresponds to -0.50 (-0.8; 0.2) SD according to the T-criterion, in the lumbar spine – 1.19 (1.10; 1.275) g/cm2and 0.1 (-0.6; 0.8) SD according to the T-criterion. BMD in the femoral neck in the group of patients with presarcopenia (group 2) – 0.995 (0.94; 1.04) g/cm2and -0.3 (-0.70; 0) SD according to the T-criterion, in the lumbar spine – 1.32 (1.24; 1.40) g/cm2and 1.20 (0.50; 1.90) SD according to the T-criterion. In patients with established sarcopenia (group 3), the following indicators of BMD and T-criterion were recorded: 0.95 (0.845; 0.98) g/cm2and -0.60 (-1.40; -0.40) SD and 1.23 (0.085; 1.31) g/cm2and 0.4 (-0.8; 1.1) SD in the femoral neck and lumbar spine, respectively.A comparative analysis of the results of the DXA found that patients with sarcopenia had a significant decrease in the BMD and T-criterion in the femoral neck compared to patients with presarcopenia (p=0.039 and p=0.040, respectively). There were no differences between the groups of patients without sarcopenia and with sarcopenia and presarcopenia (p>0.05).It was found that patients with sarcopenia had significantly lower BMD and T-criterion in the lumbar spine compared to patients with presarcopenia (p=0.017 and p=0.0165, respectively). The values of the BMD and T-criterion in the groups of patients without sarcopenia and with presarcopenia and sarcopenia in the lumbar spine were comparable (p>0.05).Conclusion:The presence of sarcopenia is associated with loss of BMD in the femoral neck and in the lumbar spine. The results obtained confirm the high probability of common pathogenetic links between OP and sarcopenia.Disclosure of Interests:None declared


Sign in / Sign up

Export Citation Format

Share Document