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Nutrients Jun 2022Recovery strategies, both in the general population and in athletes, must be aimed at the main causes of fatigue [...].
Recovery strategies, both in the general population and in athletes, must be aimed at the main causes of fatigue [...].
Topics: Athletes; Fatigue; Humans; Muscle Fatigue; Muscle, Skeletal; Nutritional Status
PubMed: 35745146
DOI: 10.3390/nu14122416 -
International Journal of Molecular... Oct 2021Muscle fatigue (MF) declines the capacity of muscles to complete a task over time at a constant load. MF is usually short-lasting, reversible, and is experienced as a... (Review)
Review
Muscle fatigue (MF) declines the capacity of muscles to complete a task over time at a constant load. MF is usually short-lasting, reversible, and is experienced as a feeling of tiredness or lack of energy. The leading causes of short-lasting fatigue are related to overtraining, undertraining/deconditioning, or physical injury. Conversely, MF can be persistent and more serious when associated with pathological states or following chronic exposure to certain medication or toxic composites. In conjunction with chronic fatigue, the muscle feels floppy, and the force generated by muscles is always low, causing the individual to feel frail constantly. The leading cause underpinning the development of chronic fatigue is related to muscle wasting mediated by aging, immobilization, insulin resistance (through high-fat dietary intake or pharmacologically mediated Peroxisome Proliferator-Activated Receptor (PPAR) agonism), diseases associated with systemic inflammation (arthritis, sepsis, infections, trauma, cardiovascular and respiratory disorders (heart failure, chronic obstructive pulmonary disease (COPD))), chronic kidney failure, muscle dystrophies, muscle myopathies, multiple sclerosis, and, more recently, coronavirus disease 2019 (COVID-19). The primary outcome of displaying chronic muscle fatigue is a poor quality of life. This type of fatigue represents a significant daily challenge for those affected and for the national health authorities through the financial burden attached to patient support. Although the origin of chronic fatigue is multifactorial, the MF in illness conditions is intrinsically linked to the occurrence of muscle loss. The sequence of events leading to chronic fatigue can be schematically denoted as: trigger (genetic or pathological) -> molecular outcome within the muscle cell -> muscle wasting -> loss of muscle function -> occurrence of chronic muscle fatigue. The present review will only highlight and discuss current knowledge on the molecular mechanisms that contribute to the upregulation of muscle wasting, thereby helping us understand how we could prevent or treat this debilitating condition.
Topics: Autophagy; COVID-19; Critical Illness; Humans; Insulin Resistance; Lysosomes; Muscle Fatigue; Muscle Proteins; Muscle, Skeletal; Muscular Atrophy; Sarcopenia
PubMed: 34769017
DOI: 10.3390/ijms222111587 -
International Journal of Sports Medicine Dec 2022Fatigue is a phenomenon associated with decreases in both physical and cognitive performances and increases in injury occurrence. Competitive athletes are required to... (Review)
Review
Fatigue is a phenomenon associated with decreases in both physical and cognitive performances and increases in injury occurrence. Competitive athletes are required to complete demanding training programs with high workloads to elicit the physiological and musculoskeletal adaptations plus skill acquisition necessary for performance. High workloads, especially sudden rapid increases in training loads, are associated with the occurrence of fatigue. At present, there is limited evidence elucidating the underlying mechanisms associating the fatigue generated by higher workloads and with an increase in injury risk. The multidimensional nature and manifestation of fatigue have led to differing definitions and dichotomies of the term. Consequently, a plethora of physiological, biochemical, psychological and performance markers have been proposed to measure fatigue and recovery. Those include self-reported scales, countermovement jump performance, heart rate variability, and saliva and serum biomarker analyses. The purpose of this review is to provide an overview of fatigue and recovery plus methods of assessments.
Topics: Humans; Athletic Performance; Fatigue; Muscle Fatigue; Workload; Heart Rate; Athletes
PubMed: 35468639
DOI: 10.1055/a-1834-7177 -
Overview of muscle fatigue differences between maximal eccentric and concentric resistance exercise.Scandinavian Journal of Medicine &... Oct 2023Since the 1970s, researchers have studied a potential difference in muscle fatigue (acute strength loss) between maximal eccentric (ECC ) and concentric (CON )... (Review)
Review
Since the 1970s, researchers have studied a potential difference in muscle fatigue (acute strength loss) between maximal eccentric (ECC ) and concentric (CON ) resistance exercise. However, a clear answer to whether such a difference exists has not been established. Therefore, the aim of our paper was to overview methods and results of studies that compared acute changes in muscle strength after bouts of ECC and CON resistance exercise. We identified 30 relevant studies. Participants were typically healthy men aged 20-40 years. Exercise usually consisted of 40-100 isokinetic ECC and CON repetitions of the knee extensors or elbow flexors. Both ECC and CON exercise caused significant strength loss, which plateaued and rarely exceeded 60% of baseline, suggesting strength preservation. In upper-body muscles, strength loss at the end of ECC (31.4 ± 20.4%) and CON (33.6 ± 17.5%) exercise was similar, whereas in lower-body muscles, strength loss was less after ECC (13.3 ± 12.2%) than CON (39.7 ± 13.3%) exercise. Muscle architecture and daily use of lower-body muscles likely protects lower-body muscles from strength loss during ECC exercise. We also reviewed seven studies on muscle fatigue during coupled ECC -CON exercise and found similar strength loss in the ECC and CON phases. We also found evidence from three studies that more ECC than CON repetitions can be completed at equal relative loads. These results indicate that muscle fatigue may manifest differently between ECC and CON resistance exercise. An implication of the results is that prescriptions of ECC resistance exercise for lower-body muscles should account for greater fatigue resilience of these muscles compared to upper-body muscles.
Topics: Male; Humans; Muscle Fatigue; Muscle, Skeletal; Resistance Training; Exercise; Muscle Strength
PubMed: 37269142
DOI: 10.1111/sms.14419 -
Oxidative Medicine and Cellular... 2019The effects of preexercise photobiomodulation therapy (PBMT) to enhance performance, accelerate recovery, and attenuate exercise-induced oxidative stress were still not... (Randomized Controlled Trial)
Randomized Controlled Trial
Infrared Low-Level Laser Therapy (Photobiomodulation Therapy) before Intense Progressive Running Test of High-Level Soccer Players: Effects on Functional, Muscle Damage, Inflammatory, and Oxidative Stress Markers-A Randomized Controlled Trial.
The effects of preexercise photobiomodulation therapy (PBMT) to enhance performance, accelerate recovery, and attenuate exercise-induced oxidative stress were still not fully investigated, especially in high-level athletes. The aim of this study was to evaluate the effects of PBMT (using infrared low-level laser therapy) applied before a progressive running test on functional aspects, muscle damage, and inflammatory and oxidative stress markers in high-level soccer players. A randomized, triple-blind, placebo-controlled crossover trial was performed. Twenty-two high-level male soccer players from the same team were recruited and treated with active PBMT and placebo. The order of interventions was randomized. Immediately after the application of active PBMT or placebo, the volunteers performed a standardized high-intensity progressive running test (ergospirometry test) until exhaustion. We analyzed rates of oxygen uptake (VO), time until exhaustion, and aerobic and anaerobic threshold during the intense progressive running test. Creatine kinase (CK) and lactate dehydrogenase (LDH) activities, levels of interleukin-1 (IL-1-), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-), levels of thiobarbituric acid (TBARS) and carbonylated proteins, and catalase (CAT) and superoxide dismutase (SOD) activities were measured before and five minutes after the end of the test. PBMT increased the VO (both relative and absolute values- < 0.0467 and < 0.0013, respectively), time until exhaustion ( < 0.0043), time ( < 0.0007) and volume ( < 0.0355) in which anaerobic threshold happened, and volume in which aerobic threshold happened ( < 0.0068). Moreover, PBMT decreased CK ( < 0.0001) and LDH ( < 0.0001) activities. Regarding the cytokines, PBMT decreased only IL-6 ( < 0.0001). Finally, PBMT decreased TBARS ( < 0.0001) and carbonylated protein levels ( < 0.01) and increased SOD ( < 0.0001)and CAT ( < 0.0001) activities. The findings of this study demonstrate that preexercise PBMT acts on different functional aspects and biochemical markers. Moreover, preexercise PBMT seems to play an important antioxidant effect, decreasing exercise-induced oxidative stress and consequently enhancing athletic performance and improving postexercise recovery. This trial is registered with Clinicaltrials.gov NCT03803956.
Topics: Adolescent; Adult; Athletes; Biomarkers; Cross-Over Studies; Exercise; Humans; Inflammation; Low-Level Light Therapy; Male; Muscle Fatigue; Oxidation-Reduction; Oxidative Stress; Running; Soccer; Young Adult
PubMed: 31827687
DOI: 10.1155/2019/6239058 -
Experimental Physiology Dec 2021
Topics: Fatigue; Humans; Muscle Fatigue; Physical Endurance
PubMed: 34852402
DOI: 10.1113/EP089942 -
European Journal of Applied Physiology Mar 2021This review integrates from the single muscle fibre to exercising human the current understanding of the role of skeletal muscle for whole-body potassium (K) regulation,... (Review)
Review
This review integrates from the single muscle fibre to exercising human the current understanding of the role of skeletal muscle for whole-body potassium (K) regulation, and specifically the regulation of skeletal muscle [K]. We describe the K transport proteins in skeletal muscle and how they contribute to, or modulate, K disturbances during exercise. Muscle and plasma K balance are markedly altered during and after high-intensity dynamic exercise (including sports), static contractions and ischaemia, which have implications for skeletal and cardiac muscle contractile performance. Moderate elevations of plasma and interstitial [K] during exercise have beneficial effects on multiple physiological systems. Severe reductions of the trans-sarcolemmal K gradient likely contributes to muscle and whole-body fatigue, i.e. impaired exercise performance. Chronic or acute changes of arterial plasma [K] (hyperkalaemia or hypokalaemia) have dangerous health implications for cardiac function. The current mechanisms to explain how raised extracellular [K] impairs cardiac and skeletal muscle function are discussed, along with the latest cell physiology research explaining how calcium, β-adrenergic agonists, insulin or glucose act as clinical treatments for hyperkalaemia to protect the heart and skeletal muscle in vivo. Finally, whether these agents can also modulate K-induced muscle fatigue are evaluated.
Topics: Exercise; Humans; Muscle Fatigue; Muscle, Skeletal; Potassium
PubMed: 33392745
DOI: 10.1007/s00421-020-04546-8 -
Biomolecules Dec 2023Metabolic myopathies are a group of genetic disorders that affect the normal functioning of muscles due to abnormalities in metabolic pathways. These conditions result... (Review)
Review
Metabolic myopathies are a group of genetic disorders that affect the normal functioning of muscles due to abnormalities in metabolic pathways. These conditions result in impaired energy production and utilization within muscle cells, leading to limitations in muscle function with concomitant occurrence of related signs and symptoms, among which fatigue is one of the most frequently reported. Understanding the underlying molecular mechanisms of muscle fatigue in these conditions is challenging for the development of an effective diagnostic and prognostic approach to test targeted therapeutic interventions. This paper outlines the key biomolecules involved in muscle fatigue in metabolic myopathies, including energy substrates, enzymes, ion channels, and signaling molecules. Potential future research directions in this field are also discussed.
Topics: Humans; Muscle Fatigue; Muscular Diseases; Metabolism, Inborn Errors; Muscles; Muscle Cells
PubMed: 38254650
DOI: 10.3390/biom14010050 -
Experimental Brain Research Jun 2022The objective was to measure the corticospinal excitability and motoneuron responsiveness of the right and left Biceps Brachii (BB), and left Abductor Digiti Minimi...
The objective was to measure the corticospinal excitability and motoneuron responsiveness of the right and left Biceps Brachii (BB), and left Abductor Digiti Minimi (ADM) muscles in response to submaximal isotonic fatiguing contractions performed by the right BB muscle. With the familiarization session, ten young moderately active male subjects came to the lab on seven occasions. Three sets of 3 min seated elbow curls at 25% of one-repetition maximum (1RM) separated by a 1-min rest performed by the right BB muscle were used as the fatiguing protocol. The motor evoked potential (MEP), cervicomedullary motor evoked potential (CMEP), and compound muscle action potential (Mmax) of the right BB muscle (baseline and after each set of the fatiguing task), the left BB and ADM muscles (baseline, post-fatigue, post-10, and post-20 min) were measured. MEP and CMEP were then normalized to Mmax for statistical analysis. The results showed that in the right BB muscle, there was a significant reduction in the MEP after performing the fatiguing task (p= 0.03), while no significant effect of time was seen in the CMEP (p= 0.07). In the left BB muscle, the MEP significantly decreased from pre-fatigue to post-fatigue (p= 0.01) and post-10 (p= 0.001), while there was a significant decline in the CMEP post-fatigue (p= 0.03). In the left ADM muscle, MEP significantly decreased post-fatigue (p= 0.03) and no changes were seen in the CMEP (p= 0.12). These results not only confirm the incidence of non-local muscle fatigue (NLMF) in response to performing submaximal isotonic fatiguing contractions but also as a new finding, imply that both spinal and supraspinal modulations account for the NLMF response.
Topics: Electric Stimulation; Electromyography; Evoked Potentials, Motor; Humans; Male; Muscle Contraction; Muscle Fatigue; Muscle, Skeletal; Pyramidal Tracts; Transcranial Magnetic Stimulation
PubMed: 35460346
DOI: 10.1007/s00221-022-06364-0 -
European Journal of Applied Physiology Nov 2023Hamstring injuries in soccer reportedly increase towards the end of the matches' halves as well as with increased match frequency in combination with short rest periods,... (Randomized Controlled Trial)
Randomized Controlled Trial
PURPOSE
Hamstring injuries in soccer reportedly increase towards the end of the matches' halves as well as with increased match frequency in combination with short rest periods, possibly due to acute or residual fatigue. Therefore, this study aimed to investigate the effects of acute and residual muscle fatigue on exercise-induced hamstring muscle damage.
METHODS
A three-armed randomized-controlled trial, including 24 resistance-trained males, was performed allocating subjects to either a training group with acute muscle fatigue + eccentric exercise (AF/ECC); residual muscle fatigue + eccentric exercise (RF/ECC) or a control group with only eccentric exercise (ECC). Muscle stiffness, thickness, contractility, peak torque, range of motion, pain perception, and creatine kinase were assessed as muscle damage markers pre, post, 1 h post, and on the consecutive three days.
RESULTS
Significant group × time interactions were revealed for muscle thickness (p = 0.02) and muscle contractility parameters radial displacement (D) and contraction velocity (V) (both p = 0.01), with larger changes in the ECC group (partial η = 0.4). Peak torque dropped by an average of 22% in all groups; stiffness only changed in the RF/ECC group (p = 0.04). Muscle work during the damage protocol was lower for AF/ECC than for ECC and RF/ECC (p = 0.005).
CONCLUSION
Hamstring muscle damage was comparable between the three groups. However, the AF/ECC group resulted in the same amount of muscle damage while accumulating significantly less muscle work during the protocol of the damage exercise.
TRIAL REGISTRATION
This study was preregistered in the international trial registration platform (WHO; registration number: DRKS00025243).
Topics: Male; Humans; Muscle Fatigue; Hamstring Muscles; Muscle, Skeletal; Isometric Contraction; Arm; Torque
PubMed: 37330434
DOI: 10.1007/s00421-023-05234-z