Muscle growth resistance exercise

INTRODUCTION: Microvascular perfusion is essential for post-exercise skeletal muscle recovery to ensure adequate delivery of nutrients and growth factors. This study assessed the relationship between various indices of muscle fiber capillarization and microvascular perfusion assessed by contrast-enhanced ultrasound (CEUS) at rest and during recovery from a bout of resistance exercise in older adults. METHODS: Sixteen older adults (72±6 y, 5/11 male/female) participated in an experimental test day during which a muscle biopsy was collected from the vastus lateralis and microvascular perfusion was determined by CEUS at rest and at 10 and 40 min following a bout of resistance exercise...

We investigated fast and slow muscle fiber transcriptome exercise dynamics among three groups of men: Lifelong exercisers (LLE, n=8, 74±1 y), old healthy non-exercisers (OH, n=9, 75±1 y), and young exercisers (YE, n=8, 25±1 y). Muscle biopsies were obtained pre- and 4h post-resistance exercise (3x10 knee extensions, 70% 1-RM). Fast and slow fiber size and function were assessed pre-exercise with fast and slow RNA-seq examined pre- and post-exercise. LLE fast fiber size was similar to OH, which were ~30% smaller than YE (P<0...

Cancer is a major cause of morbidity and mortality worldwide, and the incidence is increasing, highlighting the need for effective strategies to treat this disease. Exercise has emerged as fundamental therapeutic medicine in the management of cancer, associated with a lower risk of recurrence and increased survival. Several avenues of research demonstrate reduction in growth, proliferation, and increased apoptosis of cancer cells, including breast, prostate, colorectal, and lung cancer, when cultured by serum collected after exercise in vitro (i...

This study aimed to assess the impact of different resistance training (RT) loads and repetition on muscle damage, intramuscular anabolic signaling, and maximal muscle strength (MMS) in weightlifters. Eighteen male weightlifters were randomly assigned to 8 weeks of supervised RT regimes: high-load, low-repetition (HL), low-load, high-repetition (LH), and combination of HL and LH (COMBI). All groups exhibited a significant increase in skeletal muscle mass (SMM) and growth hormone levels, which ultimately contributed to improvement in MMS as indicated by 1-repetition maximum in the back squat and back muscle strength...

BACKGROUND: Water treadmill (WT) exercise is a popular modality for the training and rehabilitation of horses. However, evidence-based literature regarding the use of WT exercise, particularly using inclines, is lacking. OBJECTIVES: The aim of this study was to assess the effect of recurring inclined WT sessions on equine epaxial muscle development. METHODS: Six horses completed 24 sessions of 15 minutes of WT activity over four weeks...

BACKGROUND: Resistance exercise is beneficial in patients with lower extremity arterial disease. Muscle-derived exosomes contain many types of signaling molecules, including microRNAs (miRNAs). Here, we tested the hypothesis that exosomal miRNAs secreted by growing muscles promote an angiogenic response in endothelial cells (ECs).Methods and Results: Skeletal muscle-specific conditional Akt1 transgenic (Akt1-TG) mice, in which skeletal muscle growth can be induced were used as a model of resistance training...

BACKGROUND: The related functions of skeletal muscle and brain decrease significantly with age, and muscle-brain-related diseases are primarily associated with each other. Exercise can promote the secretion of myokines in skeletal muscle, showing a beneficial effect on the function of both, reflecting muscle-brain crosstalk. However, the key mechanism of action of exercise-regulated myokines in muscle-brain diseases remains unclear. SUMMARY: This review is intended to sort out and explore the key mechanism of the effect of exercise regulatory myokines on muscle-brain diseases through summarizing the relevant literature on the level of motor regulatory myokines in recent years and pay special attention to the impact of exercise type, intensity, and duration on myokine expression levels...

Mice are often used in gain or loss of function studies to understand how genes regulate metabolism and adaptation to exercise in skeletal muscle. Once-daily resistance training with electrical nerve stimulation produces hypertrophy of the dorsiflexors in rat, but not in mouse. Using implantable pulse generators, we assessed the acute transcriptional response (1-h post-exercise) after 2, 10, and 20 days of training in free-living mice and rats using identical nerve stimulation paradigms. RNA sequencing revealed strong concordance in the timecourse of many transcriptional responses in the tibialis anterior muscles of both species including responses related to "stress responses/immediate-early genes, and "collagen homeostasis," "ribosomal subunits," "autophagy," and "focal adhesion...

Accelerated biological vascular ageing is still a major driver of the increasing burden of cardiovascular disease and mortality. Exercise training delays this process, known as early vascular ageing, but often lacks effectiveness due to a lack of understanding of molecular and clinical adaptations to specific stimuli. This narrative review summarizes the current knowledge about the molecular and clinical vascular adaptations to acute and chronic exercise. It further addresses how training characteristics (frequency, intensity, volume, and type) may influence these processes...

BACKGROUND: A proprietary combination of Garcinia mangostana fruit rind and Cinnamomum tamala leaf extracts (LI80020F4, CinDura® ) improved the physical performance and muscle strength of resistance-trained adult males. OBJECTIVE: This study assessed the underlying mechanisms of the ergogenic potential of LI80020F4 in in vitro and in vivo models. METHODS: The individual extracts and their combination (LI80020F4) were assessed for nitrite production in EAhy926 human endothelial cells...

We examined how set-volume equated resistance training using either the back squat (SQ) or hip thrust (HT) affected hypertrophy and various strength outcomes. Untrained college-aged participants were randomized into HT (n = 18) or SQ (n = 16) groups. Surface electromyograms (sEMG) from the right gluteus maximus and medius muscles were obtained during the first training session. Participants completed 9 weeks of supervised training (15-17 sessions), before and after which gluteus and leg muscle cross-sectional area (mCSA) was assessed via magnetic resonance imaging...

Muscle mass is balanced between hypertrophy and atrophy by cellular processes, including activation of the protein kinase B-mechanistic target of rapamycin (Akt-mTOR) signaling cascade. Stressors apart from exercise and nutrition, such as heat stress, can stimulate the heat shock protein A (HSPA) and C (HSPC) families alongside hypertrophic signaling factors and muscle growth. The effects of heat stress on HSP expression and Akt-mTOR activation in human skeletal muscle and their magnitude of activation compared with known hypertrophic stimuli are unclear...

Nutrition in sports, as a branch of nutritional science, is a constantly developing field with a growing number of scientific researches and recommendations concerning the justification of the diet composition to ensure the requirements for macro- and micronutrients of the athlete's body at different stages of sports activity and energy value, as well as the use of special dietary supplements of various nature, including protein in forms of specialized dry mixes, drinks, etc. The aim of the research was to present the results of studies conducted abroad, presented in review publications and original articles, on the role of protein and the impact of its various levels of consumption on the maintenance of muscle mass as a criterion for the effectiveness of diets used, including in conditions of their reduced calorie content; on the safety of consuming significantly higher than recommended amounts of protein (>2...

The development of sarcopenia in the elderly is associated with many potential factors and/or processes that impair the renovation and maintenance of skeletal muscle mass and strength as ageing progresses. Among them, a defect by skeletal muscle to respond to anabolic stimuli is to be considered. Common anabolic stimuli/signals in skeletal muscle are hormones (insulin, growth hormones, IGF-1, androgens, and β-agonists such epinephrine), substrates (amino acids such as protein precursors on top, but also glucose and fat, as source of energy), metabolites (such as β-agonists and HMB), various biochemical/intracellular mediators), physical exercise, neurogenic and immune-modulating factors, etc...

An increase in mechanical loading, such as that which occurs during resistance exercise, induces radial growth of muscle fibers (i.e., an increase in cross-sectional area). Muscle fibers are largely composed of myofibrils, but whether radial growth is mediated by an increase in the size of the myofibrils (i.e., myofibril hypertrophy) and/or the number of myofibrils (i.e., myofibrillogenesis) is not known. Electron microscopy (EM) can provide images with the level of resolution that is needed to address this question, but the acquisition and subsequent analysis of EM images is a time- and cost-intensive process...

INTRODUCTION: Heavy-load free-flow resistance exercise (HL-FFRE) is a widely used training modality. Recently, low-load blood-flow restricted resistance exercise (LL-BFRRE) has gained attention in both athletic and clinical settings as an alternative when conventional HL-FFRE is contraindicated or not tolerated. LL-BFRRE has been shown to result in physiological adaptations in muscle and connective tissue that are comparable to those induced by HL-FFRE. The underlying mechanisms remain unclear; however, evidence suggests that LL-BFRRE involves elevated metabolic stress compared to conventional free-flow resistance exercise (FFRE)...

Whole-body vibration (WBV) is a type of light-resistance exercise that involves exposing the body to rapid and repeated oscillations of a vibrating platform. It has been suggested that long-term WBV can improve bone mass and muscle strength. However, little is known about its effects on body composition, and the safety and efficacy of WBV have not been established. In this study, we investigated the effects of WBV on body fat loss and muscle mass maintenance or improvement in male Wistar rats fed standard or high-fat diets...

Cell swelling caused by resistance training is proposed to provide an anabolic stimulus for muscle growth and it is believed that these effects are heightened with the use of low loads. The purpose of this study was to compare the acute effects of two volume-equated resistance training (RT) protocols, low-load (LL) versus high-load (HL), on elbow flexor muscles thickness, arm circumference, and blood lactate concentration in well-trained individuals. Eight resistance-trained males performed the following two RT protocols involving unilateral elbow flexion of the dominant arm: i) LL, four sets with 50% 1 repetition-maximum [1 RM] and ii) HL, ten sets with 85% 1 RM until failure, and equated volume...

BACKGROUND: Prehabilitation with exercise interventions during neoadjuvant chemotherapy (NACT) is effective in reducing physical and psychosocial chemotherapy-related adverse events in patients with cancer. In preclinical studies, data also support a growth inhibitory effect of aerobic exercise on the tumour microenvironment with possible improved chemotherapy delivery but evidence in human patients is limited. The aim of the study here described is to investigate if supervised exercise with high-intensity aerobic and resistance training during NACT can improve tumour reduction in patients with breast cancer...

PURPOSE: Skeletal muscle regulates health and performance by maintaining or increasing strength and muscle mass. Although the molecular mechanisms in response to resistance exercise (RE) significantly target the activation of protein synthesis, a plethora of other mechanisms and structures must be involved in orchestrating the communication, repair, and restoration of homeostasis after RE stimulation. In practice, RE can be modulated by variations in intensity, continuity and volume, which affect molecular responses and skeletal muscle adaptation...