Effects of Exercise in Patients With Amyotrophic Lateral Sclerosis: A Systematic Review and Meta-Analysis

Examining the Interaction between Exercise, Gut Microbiota, and Neurodegeneration: Future Research Directions

Physical activity has been demonstrated to have a significant impact on gut microbial diversity and function. Emerging research has revealed certain aspects of the complex interactions between the gut, exercise, microbiota, and neurodegenerative diseases, suggesting that changes in gut microbial diversity and metabolic function may have an impact on the onset and progression of neurological conditions. This study aimed to review the current literature from several databases until 1 June 2023 (PubMed/MEDLINE, Web of Science, and Google Scholar) on the interplay between the gut, physical exercise, microbiota, and neurodegeneration. We summarized the roles of exercise and gut microbiota on neurodegeneration and identified the ways in which these are all connected. The gut-brain axis is a complex and multifaceted network that has gained considerable attention in recent years. Research indicates that gut microbiota plays vital roles in metabolic shifts during physiological or pathophysiological conditions in neurodegenerative diseases; therefore, they are closely related to maintaining overall health and well-being. Similarly, exercise has shown positive effects on brain health and cognitive function, which may reduce/delay the onset of severe neurological disorders. Exercise has been associated with various neurochemical changes, including alterations in cortisol levels, increased production of endorphins, endocannabinoids like anandamide, as well as higher levels of serotonin and dopamine. These changes have been linked to mood improvements, enhanced sleep quality, better motor control, and cognitive enhancements resulting from exercise-induced effects. However, further clinical research is necessary to evaluate changes in bacteria taxa along with age- and sex-based differences.

Iranian clinical practice guideline for amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegeneration involving motor neurons. The 3-5 years that patients have to live is marked by day-to-day loss of motor and sometimes cognitive abilities. Enormous amounts of healthcare services and resources are necessary to support patients and their caregivers during this relatively short but burdensome journey. Organization and management of these resources need to best meet patients' expectations and health system efficiency mandates. This can only occur in the setting of multidisciplinary ALS clinics which are known as the gold standard of ALS care worldwide. To introduce this standard to the care of Iranian ALS patients, which is an inevitable quality milestone, a national ALS clinical practice guideline is the necessary first step. The National ALS guideline will serve as the knowledge base for the development of local clinical pathways to guide patient journeys in multidisciplinary ALS clinics. To this end, we gathered a team of national neuromuscular experts as well as experts in related specialties necessary for delivering multidisciplinary care to ALS patients to develop the Iranian ALS clinical practice guideline. Clinical questions were prepared in the Patient, Intervention, Comparison, and Outcome (PICO) format to serve as a guide for the literature search. Considering the lack of adequate national/local studies at this time, a consensus-based approach was taken to evaluate the quality of the retrieved evidence and summarize recommendations.

A meta-analysis of post-exercise outcomes in people with amyotrophic lateral sclerosis

Objective

To systematically evaluate post-exercise outcomes related to function and quality of life in people with ALS.

Methods

PRISMA guidelines were used for identifying and extracting articles. Levels of evidence and quality of articles were judged based on The Oxford Centre for Evidence-based Medicine Levels of Evidence and the QualSyst. Outcomes were analyzed with Comprehensive Meta-Analysis V2 software, random effects models, and Hedge's G. Effects were examined at 0-4 months, up to 6 months, and > 6 months. Pre-specified sensitivity analyses were performed for 1) controlled trials vs. all studies and 2) ALSFRS-R bulbar, respiratory, and motor subscales. Heterogeneity of pooled outcomes was computed with the I² statistic.

Results

16 studies and seven functional outcomes met inclusion for the meta-analysis. Of the outcomes explored, the ALSFRS-R demonstrated a favorable summary effect size and had acceptable heterogeneity and dispersion. While FIM scores demonstrated a favorable summary effect size, heterogeneity limited interpretations. Other outcomes did not demonstrate a favorable summary effect size and/or could not be reported due to few studies reporting outcomes.

Conclusions

This study provides inconclusive guidance regarding exercise regimens to maintain function and quality of life in people with ALS due to study limitations (e.g., small sample size, high attrition rate, heterogeneity in methods and participants, etc.). Future research is warranted to determine optimal treatment regimens and dosage parameters in this patient population.

Brain Vascular Health in ALS Is Mediated through Motor Cortex Microvascular Integrity

Brain vascular health appears to be critical for preventing the development of amyotrophic lateral sclerosis (ALS) and slowing its progression. ALS patients often demonstrate cardiovascular risk factors and commonly suffer from cerebrovascular disease, with evidence of pathological alterations in their small cerebral blood vessels. Impaired vascular brain health has detrimental effects on motor neurons: vascular endothelial growth factor levels are lowered in ALS, which can compromise endothelial cell formation and the integrity of the blood-brain barrier. Increased turnover of neurovascular unit cells precedes their senescence, which, together with pericyte alterations, further fosters the failure of toxic metabolite removal. We here provide a comprehensive overview of the pathogenesis of impaired brain vascular health in ALS and how novel magnetic resonance imaging techniques can aid its detection. In particular, we discuss vascular patterns of blood supply to the motor cortex with the number of branches from the anterior and middle cerebral arteries acting as a novel marker of resistance and resilience against downstream effects of vascular risk and events in ALS. We outline how certain interventions adapted to patient needs and capabilities have the potential to mechanistically target the brain microvasculature towards favorable motor cortex blood supply patterns. Through this strategy, we aim to guide novel approaches to ALS management and a better understanding of ALS pathophysiology.

Safety and Efficacy of Edaravone in Patients with Amyotrophic Lateral Sclerosis: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVE

The efficacy and safety of edaravone for the treatment of amyotrophic lateral sclerosis (ALS) remain unclear. The aim of this meta-analysis was to provide evidence-based medical guidance and advice for the clinical application of edaravone in the treatment of ALS.

METHODS

PubMed, Embase, Chinese Biomedical Literature Database (CBM), Cochrane Library and Web of Science were searched through 09 March 2022 for randomized controlled trials (RCTs) on the safety and efficacy of edaravone versus placebo during follow-up of patients with ALS. A summary of the outcome measures with GRADE was performed. This study was registered on PROSPERO (ID: CRD 42022319997).

RESULTS

Five RCTs with a total of 566 participants were included, and there was a significant difference (mean difference [MD] 1.33, 95% confidence interval [CI] 0.33-2.34; p = 0.009) in the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) score between the treatment and placebo groups. The edaravone group had an increased grip strength (MD 0.26, 95% CI 0.03-0.49; p = 0.03) and modified Norris Scale score (MD 2.81, 95% CI 1.18-4.43; p = 0.0007). However, there were no significant differences between groups for the change in forced vital capacity (FVC)% (MD 0.55, 95% CI - 3.15 to 4.24; p = 0.77), pinch strength (MD 0.05, 95% CI - 0.05 to 0.16; p = 0.33) or Amyotrophic Lateral Sclerosis Assessment Questionnaire (ALSAQ-40) score (MD - 4.76, 95% CI - 9.56 to 0.03; p = 0.05). The incidence of adverse events (AEs) (risk ratio [RR] 0.09, 95% CI 0.93-1.05; p = 0.65), serious adverse events (SAEs) (RR 0.72, 95% CI 0.52-1.00; p = 0.05) and the number of deaths (risk difference [RD] 0.00, 95% CI - 0.02 to 0.03; p = 0.83) were not statistically different from the placebo group. The quality of evidence was low only for SAEs, and the remaining outcome measures were of moderate quality.

CONCLUSIONS

Compared with placebo, edaravone may provide potential clinical benefits in the treatment of ALS and may not increase the number of AEs and deaths. However, due to the low-quality evidence of the included studies and the small sample size, more high-quality and high-standard research evidence is needed to confirm these results.

PROTOCOL REGISTRATION

This study was registered on PROSPERO (ID: CRD 42022319997).

Differential Diagnosis or Etiology: A Case Report on Amyotrophic Lateral Sclerosis-like Neuropathy Associated with HIV Infection

BACKGROUND

Retroviruses are described as a risk factor for chronic neuropathy. However, it is still unknown if they can work as amyotrophic lateral sclerosis triggers. Over the years, some cases of this association have been described with heterogenous disclosures.

CASE REPRESENTATION

This study aimed to report a case of HIV and ALS-like neuropathy and briefly discuss peculiarities of clinical aspects, such as physiopathology and treatment options. The patient underwent neurological examination associated with blood tests, electromyography, analysis of cerebrospinal fluid, and imaging studies.

DISCUSSION

A non-systematic review was performed in major databases regarding the topic. The case presented mixed upper and lower motor neuron signs and was framed as a probable case of ALS following the present criteria.

CONCLUSION

After a short follow-up and viral load cleansing, neurological stabilization was achieved.

Physical Activity in People With Motor Neuron Disease: Validity of the Physical Activity Scale for the Elderly as a Measuring Tool

OBJECTIVE

This study aimed to investigate whether the physical activity scale for the elderly (PASE) is a valid tool in measuring physical activity (PA) in people with motor neuron disease (MND) and to identify the demographic and clinical factors that predict PA participation in this population.

DESIGN

A prospective, observational study involving 100 ambulant participants with MND.

SETTING

This study was conducted at a multidisciplinary specialist MND clinic. The clinic is fully funded by the local public health system and patients receiving care here are not expected to pay for their consultation.

PARTICIPANTS

190 patients with MND who had a physiotherapy appointment at the specialist clinic between July and October 2018 were screened. Of these, 100 participants (mean age 67 years [SD=12], 64% [n=64] men) who were ambulant (with or without assistance) were recruited (N=100).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

PASE questionnaire, amyotrophic lateral sclerosis functional rating scale-Revised (ALSFRS-r), forced vital capacity (FVC).

RESULTS

The results showed that engagement in PA is generally low, with median PASE score of 57. The PASE had fair-moderate correlation with ALSFRS-R total scores (rho=0.607; P<.000) and FVC (rho=0.250; P=.030). Standard multiple regression analyses showed that disease severity (ALSFRS-R total score) was the strongest predictor of PA levels (β= 0.54; 95% confidence interval 0.02,0.06). The most frequently selected physical activities of choice for people with MND were activities around their homes and the biggest barrier to participation is fatigue.

CONCLUSION

Present findings suggest that the PASE can be used to measure PA participation in people with MND. Details about activity of choice and barriers to participation present important considerations in designing exercise programs in this population to maximize compliance and therefore effectiveness.

Muscular Response in ALS Patients during Maximal Bilateral Isometric Work of the Biceps Brachii until Fatigue

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative and fatal disease, characterized by the loss of motor neurons and progressive musculoskeletal deterioration. The clinical onset is mainly bulbar or spinal. Considering that there is no effective medical treatment, there is a need to understand the muscle activation patterns to design better physical exercise routines. The objective of this study was to determine muscle strength and fatigue in patients with ALS performing a unilateral exercise, and according to sex and type of ALS. A cross-sectional, analytical study was conducted with 23 patients. Five maximal unilateral isometric contractions were performed with the right and left biceps brachii. Muscle activation was calculated by surface electromyography bilaterally in the biceps brachii, triceps brachii, rectus femoris anterior, and tibialis anterior. The results showed more accentuated fatigue in men than in women, between the first and last contractions performed and especially on the dominant side (p = 0.016). In addition, there was evidence of a coactivation effect on the muscles around the work joint, which reflects a growing activation of synergists, regardless of sex or type of ALS. These findings support the use of systematic and extensive resistance exercise as a non-invasive option for maintaining the functional capacity of patients with ALS.

Physical therapy for the management of motor symptoms in amyotrophic lateral sclerosis: protocol for a systematic review

INTRODUCTION

The prescription of an intervention plan can be challenging for the physical therapist, considering clinical phenotypes, individual prognosis and the rapid, progressive and deteriorating nature of amyotrophic lateral sclerosis (ALS). In this context, therapeutic exercises (eg, resistance and aerobic exercises) for patients with ALS remain controversial and may influence the treatment plan. Therefore, this review aims to critically assess whether physical therapy interventions are effective for improving functional capacity, quality of life and fatigue of individuals with ALS.

METHODS AND ANALYSIS

Studies will be selected according to eligibility criteria, and language, geographical area or publication date will not be restricted. Four databases will be used: MEDLINE, EMBASE, Cochrane Library (CENTRAL) and Physiotherapy Evidence Database (PEDro). Searches will also be conducted on ClinicalTrials.gov and references from included studies. We plan to conduct the searches between October and December 2022. Two independent authors will examine titles and abstracts and exclude irrelevant studies and duplicates. We will assess the quality of studies and quality of evidence, and disagreements will be resolved with a third researcher. The findings will be presented in the text and tables; if possible, we will perform meta-analyses.

ETHICS AND DISSEMINATION

No ethical approval is required because this study does not involve human beings. We will publish our findings in peer-reviewed journals.

PROSPERO REGISTRATION NUMBER

CRD42021251350.

Effect of Wearable Sensor-Based Exercise on Musculoskeletal Disorders in Individuals With Neurodegenerative Diseases: A Systematic Review and Meta-Analysis

Background

The application of wearable sensor technology in an exercise intervention provides a new method for the standardization and accuracy of intervention. Considering that the deterioration of musculoskeletal conditions is of serious concern in patients with neurodegenerative diseases, it is worthwhile to clarify the effect of wearable sensor-based exercise on musculoskeletal disorders in such patients compared with traditional exercise.

Methods

Five health science-related databases, including PubMed, Cochrane Library, Embase, Web of Science, and Ebsco Cumulative Index to Nursing and Allied Health, were systematically searched. The protocol number of the study is PROSPERO CRD42022319763. Randomized controlled trials (RCTs) that were published up to March 2022 and written in English were included. Balance was the primary outcome measure, comprising questionnaires on postural stability and computerized dynamic posturography. The secondary outcome measures are motor symptoms, mobility ability, functional gait abilities, fall-associated self-efficacy, and adverse events. Stata version 16.0 was used for statistical analysis, and the weighted mean difference (WMD) was selected as the effect size with a 95% confidence interval (CI).

Results

Fifteen RCTs involving 488 participants with mean ages ranging from 58.6 to 81.6 years were included in this review, with 14 of them being pooled in a quantitative meta-analysis. Only five included studies showed a low risk of bias. The Berg balance scale (BBS) was used in nine studies, and the pooled data showed a significant improvement in the wearable sensor-based exercise group compared with the traditional exercise group after 3–12-week intervention (WMD = 1.43; 95% CI, 0.50 to 2.36, P = 0.003). A significant change in visual score was found both post-assessment and at 1-month follow-up assessment (WMD = 4.38; 95% CI, 1.69 to 7.07, P = 0.001; I2 = 0.0%). However, no significant differences were found between the two groups in the secondary outcome measures (all p > 0.05). No major adverse events were reported.

Conclusion

The wearable sensor-based exercise had advantages in improving balance in patients with neurodegenerative diseases, while there was a lack of evidence in motor symptoms, mobility, and functional gait ability enhancement. Future studies are recommended to construct a comprehensive rehabilitation treatment system for the improvement in both postural control and quality of life.

Systematic Review Registration

http://www.crd.york.ac.uk/prospero/, identifier CRD42022319763.

Effects of Ten Different Exercise Interventions on Motor Function in Parkinson’s Disease Patients—A Network Meta-Analysis of Randomized Controlled Trials

Objective: The aim of this study was to evaluate ten exercise interventions (YOGA: yoga training, RT: resistance training, AQU: aquatic training, TAI: Taiji Qigong training, TRD: treadmill training, VR: virtual reality training, DANCE: musical dance training, WKT: walking training, CYC: cycling training, BDJ: Baduanjin Qigong training) on motor function in Parkinson’s disease (PD) patients. Design: Through searching PubMed, Embase, Cochrane Library, Web of Science, and CNKI, only randomized controlled trials (RCTs) were collected to study the effects of the ten exercise interventions on motor function in patients with Parkinson’s disease. The included studies were evaluated for methodological quality by the Cochrane bias risk assessment tool. Results: The RCTs were collected between the earliest available date and April 2022. Sixty RCTs were included and the total sample size used in the study was 2859. The results of the network meta-analysis showed that DANCE can significantly improve patients’ Berg Balance Scale (BBS) (SUCRA = 78.4%); DANCE can significantly decline patients’ Unified Parkinson’s Disease Rating Scale score (UPDRS) (SUCRA = 72.3%) and YOGA can significantly decline patients’ Timed-Up-and-Go score (TUGT) (SUCRA = 78.0%). Conclusion: Based on the network meta-analysis and SUCRA ranking, we can state that dance, yoga, virtual reality training and resistance training offers better advantages than other exercise interventions for patients’ motor function.

The Short and Intensive Rehabilitation (SHAiR) Program Improves Dropped Head Syndrome Caused by Amyotrophic Lateral Sclerosis: A Case Report

Background and Objectives: Dropped head syndrome (DHS) is a syndrome that presents with correctable cervical kyphotic deformity as a result of weakening cervical paraspinal muscles. DHS with amyotrophic lateral sclerosis (ALS) is a relatively rare condition, and there is no established treatment. This is the first case report describing the improvement of both dropped head (DH) and cervical pain after the short and intensive rehabilitation (SHAiR) program in an ALS patient with DHS. Case Report: After being diagnosed with ALS in June 2020, a 75-year-old man visited our hospital in October 2020 to receive treatment for DHS. At the initial visit, the patient’s DH was prominent during standing and walking. The pain intensity of the neck was 9 out of 10 on the numerical rating scale (NRS), which was indicative of severe pain. The patient was hospitalized for 2 weeks and admitted into the SHAiR program. DH began to decrease one week after undergoing the SHAiR program and improved two weeks later. Neck pain decreased from 9 to 6 on the NRS. Results: The SHAiR program is a rehabilitation program aimed at improving DH in patients with idiopathic DHS. The program was designed to improve neck extensor and flexor function and global spinal alignment, and the program may have contributed to the improvement of DH and neck pain. Currently, reports of conservative therapies for this disease are limited to the use of cervical orthosis. Although further research is needed on the safety and indications of treatment, the SHAiR program may be a viable treatment option.

Robot-assisted training using hybrid assistive limb ameliorates gait ability in patients with amyotrophic lateral sclerosis

OBJECTIVE

The Hybrid Assistive Limb (HAL; CYBERDYNE, Inc., Japan) is a wearable robot device that provides effective gait assistance according to voluntary intention by detecting weak bioelectrical signals of neuromuscular activity on the surface of the skin. We used HAL for patients with amyotrophic lateral sclerosis (ALS) to determine whether HAL training had an effect on their gait ability.

METHODS

We conducted a single-center, single-arm, observational study. Patients with ALS underwent HAL training once per day (20-40 min per session) for 9-10 days for at least 4 weeks. Gait ability was evaluated using the 2-minute walk test, the 10-meter walk test without the assistance of HAL, and activities of daily living (ADL) using the Barthel Index and Functional Independence Measures before and after a full course of HAL training.

RESULTS

There were no dropouts or adverse events during the observation period. Gait function improved after HAL training. The 2-minute walk test revealed a mean gait distance of 73.87 m (36.65) at baseline and 89.9m (36.70) after HAL training (p = 0.004). The 10-meter walk test showed significantly improved cadence, although gait speed, step length on the 10-m walk, or ADL measurements did not change significantly.

CONCLUSIONS

Although HAL is not a curative treatment for ALS, our data suggest that HAL may be effective in ameliorating and preserving gait ability in patients with ALS.

Cognitive and Physical Intervention in Metals’ Dysfunction and Neurodegeneration

Metals—especially iron, copper and manganese—are important elements of brain functions and development. Metal-dysregulation homeostasis is associated with brain-structure damage to the motor, cognitive and emotional systems, and leads to neurodegenerative processes. There is more and more evidence that specialized cognitive and motor exercises can enhance brain function and attenuate neurodegeneration in mechanisms, such as improving neuroplasticity by altering the synaptic structure and function in many brain regions. Psychological and physical methods of rehabilitation are now becoming increasingly important, as pharmacological treatments for movement, cognitive and emotional symptoms are limited. The present study describes physical and cognitive rehabilitation methods of patients associated with metal-induced neurotoxicity such as Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, Huntington’s disease and Wilson’s disease. In our review, we describe physical (e.g., virtual-reality environments, robotic-assists training) and psychological (cognitive training, cognitive stimulation, neuropsychological rehabilitation and cognitive-behavioral and mindfulness-based therapies) methods, significantly improving the quality of life and independence of patients associated with storage diseases. Storage diseases are a diverse group of hereditary metabolic defects characterized by the abnormal cumulation of storage material in cells. This topic is being addressed due to the fact that rehabilitation plays a vital role in the treatment of neurodegenerative diseases. Unfortunately so far there are no specific guidelines concerning physiotherapy in neurodegenerative disorders, especially in regards to duration of exercise, type of exercise and intensity, as well as frequency of exercise. This is in part due to the variety of symptoms of these diseases and the various levels of disease progression. This further proves the need for more research to be carried out on the role of exercise in neurodegenerative disorder treatment.

Organ on a Chip: A Novel in vitro Biomimetic Strategy in Amyotrophic Lateral Sclerosis (ALS) Modeling

Amyotrophic lateral sclerosis is a pernicious neurodegenerative disorder that is associated with the progressive degeneration of motor neurons, the disruption of impulse transmission from motor neurons to muscle cells, and the development of mobility impairments. Clinically, muscle paralysis can spread to other parts of the body. Hence it may have adverse effects on swallowing, speaking, and even breathing, which serves as major problems facing these patients. According to the available evidence, no definite treatment has been found for amyotrophic lateral sclerosis (ALS) that results in a significant outcome, although some pharmacological and non-pharmacological treatments are currently applied that are accompanied by some positive effects. In other words, available therapies are only used to relieve symptoms without any significant treatment effects that highlight the importance of seeking more novel therapies. Unfortunately, the process of discovering new drugs with high therapeutic potential for ALS treatment is fraught with challenges. The lack of a broad view of the disease process from early to late-stage and insufficiency of preclinical studies for providing validated results prior to conducting clinical trials are other reasons for the ALS drug discovery failure. However, increasing the combined application of different fields of regenerative medicine, especially tissue engineering and stem cell therapy can be considered as a step forward to develop more novel technologies. For instance, organ on a chip is one of these technologies that can provide a platform to promote a comprehensive understanding of neuromuscular junction biology and screen candidate drugs for ALS in combination with pluripotent stem cells (PSCs). The structure of this technology is based on the use of essential components such as iPSC- derived motor neurons and iPSC-derived skeletal muscle cells on a single miniaturized chip for ALS modeling. Accordingly, an organ on a chip not only can mimic ALS complexities but also can be considered as a more cost-effective and time-saving disease modeling platform in comparison with others. Hence, it can be concluded that lab on a chip can make a major contribution as a biomimetic micro-physiological system in the treatment of neurodegenerative disorders such as ALS.

Morais L. OUP accepted manuscript

Recent research has been uncovering the role of the gut microbiota for brain health and disease. These studies highlight the role of gut microbiota on regulating brain function and behavior through immune, metabolic, and neuronal pathways. In this review we provide an overview of the gut microbiota axis pathways to lay the groundwork for upcoming sessions on the links between the gut microbiota and neurogenerative disorders. We also discuss how the gut microbiota may act as an intermediate factor between the host and the environment to mediate disease onset and neuropathology. Based on the current literature, we further examine the potential for different microbiota-based therapeutic strategies to prevent, to modify, or to halt the progress of neurodegeneration.

The Second Wind in McArdle Patients: Fitness Matters

Background: The “second wind” (SW) phenomenon—commonly referring to both an initial period of marked intolerance to dynamic exercise (e.g., brisk walking) that is not followed by perceived improvement and disappearance of previous tachycardia (i.e., the actual “SW”) until 6–10 min has elapsed—is an almost unique feature of McArdle disease that limits adherence to an active lifestyle. In this regard, an increase in the workload eliciting the SW could potentially translate into an improved patients’ exercise tolerance in daily life. We aimed to determine whether aerobic fitness and physical activity (PA) levels are correlated with the minimum workload eliciting the SW in McArdle patients—as well as with the corresponding heart rate value. We also compared the SW variables and aerobic fitness indicators in inactive vs. active patients.

Methods: Fifty-four McArdle patients (24 women, mean ± SD age 33 ± 12 years) performed 12-min constant-load and maximum ramp-like cycle-ergometer tests for SW detection and aerobic fitness [peak oxygen uptake (VO_2peak) and workload and ventilatory threshold] determination, respectively. They were categorized as physically active/inactive during the prior 6 months (active = reporting ≥150 min/week or ≥75 min/week in moderate or vigorous-intensity aerobic PA, respectively) and were also asked on their self-report of the SW.

Results: Both peak and submaximal indicators of aerobic fitness obtained in the ramp tests were significantly correlated with the workload of the SW test, with a particularly strong correlation for the VO_2peak and peak workload attained by the patients (both Pearson’s coefficients > 0.70). Twenty (seven women) and 24 patients (18 women) were categorized as physically active and inactive, respectively. Not only the aerobic fitness level [∼18–19% higher values of VO_2peak (ml⋅kg^–1⋅min^–1)] but also the workload of the SW tests was significantly higher in active than in inactive patients. All the inactive patients reported that they experienced the SW during walking/brisk walking in daily life, whereas active patients only reported experiencing this phenomenon during more strenuous activities (very brisk walking/jogging and bicycling).

Conclusion: A higher aerobic fitness and an active lifestyle are associated with a higher workload eliciting the so-called SW phenomenon in patients with McArdle disease, which has a positive impact on their exercise tolerance during daily living.

Exercise mimetics: harnessing the therapeutic effects of physical activity

Exercise mimetics are a proposed class of therapeutics that specifically mimic or enhance the therapeutic effects of exercise. Increased physical activity has demonstrated positive effects in preventing and ameliorating a wide range of diseases, including brain disorders such as Alzheimer disease and dementia, cancer, diabetes and cardiovascular disease. This article discusses the molecular mechanisms and signalling pathways associated with the beneficial effects of physical activity, focusing on effects on brain function and cognitive enhancement. Emerging therapeutic targets and strategies for the development of exercise mimetics, particularly in the field of central nervous system disorders, as well as the associated opportunities and challenges, are discussed.

Swim Training Ameliorates Hyperlocomotion of ALS Mice and Increases Glutathione Peroxidase Activity in the Spinal Cord

(1) Background: Amyotrophic lateral sclerosis (ALS) is an incurable, neurodegenerative disease. In some cases, ALS causes behavioral disturbances and cognitive dysfunction. Swimming has revealed a neuroprotective influence on the motor neurons in ALS. (2) Methods: In the present study, a SOD1-G93A mice model of ALS were used, with wild-type B6SJL mice as controls. ALS mice were analyzed before ALS onset (10th week of life), at ALS 1 onset (first symptoms of the disease, ALS 1 onset, and ALS 1 onset SWIM), and at terminal ALS (last stage of the disease, ALS TER, and ALS TER SWIM), and compared with wild-type mice. Swim training was applied 5 times per week for 30 min. All mice underwent behavioral tests. The spinal cord was analyzed for the enzyme activities and oxidative stress markers. (3) Results: Pre-symptomatic ALS mice showed increased locomotor activity versus control mice; the swim training reduced these symptoms. The metabolic changes in the spinal cord were present at the pre-symptomatic stage of the disease with a shift towards glycolytic processes at the terminal stage of ALS. Swim training caused an adaptation, resulting in higher glutathione peroxidase (GPx) and protection against oxidative stress. (4) Conclusion: Therapeutic aquatic activity might slow down the progression of ALS.

The Skeletal Muscle Emerges as a New Disease Target in Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder that leads to progressive degeneration of motor neurons (MNs) and severe muscle atrophy without effective treatment. Most research on ALS has been focused on the study of MNs and supporting cells of the central nervous system. Strikingly, the recent observations of pathological changes in muscle occurring before disease onset and independent from MN degeneration have bolstered the interest for the study of muscle tissue as a potential target for delivery of therapies for ALS. Skeletal muscle has just been described as a tissue with an important secretory function that is toxic to MNs in the context of ALS. Moreover, a fine-tuning balance between biosynthetic and atrophic pathways is necessary to induce myogenesis for muscle tissue repair. Compromising this response due to primary metabolic abnormalities in the muscle could trigger defective muscle regeneration and neuromuscular junction restoration, with deleterious consequences for MNs and thereby hastening the development of ALS. However, it remains puzzling how backward signaling from the muscle could impinge on MN death. This review provides a comprehensive analysis on the current state-of-the-art of the role of the skeletal muscle in ALS, highlighting its contribution to the neurodegeneration in ALS through backward-signaling processes as a newly uncovered mechanism for a peripheral etiopathogenesis of the disease.

Effects of a 12-week combined aerobic and strength training program in ambulatory patients with amyotrophic lateral sclerosis: a randomized controlled trial

OBJECTIVE

To compare the effectiveness of a combined aerobic, strength, and flexibility training program with flexibility alone on disease-specific and health-related symptoms in ambulatory amyotrophic lateral sclerosis (ALS) patients.

METHODS

Thirty-two ambulatory patients with ALS were equally randomized into a combined aerobic-strength intervention group or a stretching control group. The intervention period for both groups was identical, 12 consecutive weeks, two sessions per week. The combined intervention program consisted of aerobic training by recumbent cycling, flexibility achieved by stretching and passive exercises, and strength training via functional exercises. Patients in the control group performed basic stretching exercises of the upper and lower limb at home. Outcome measures included the ALS Functional Rating Scale-Revised (ALSFRS-R), respiratory function, mobility, fatigue, and quality of life and were collected 1-week prior to the intervention, after 6-weeks of training, and at the completion of the intervention.

RESULTS

Twenty-eight participants (17 males, 11 females); mean age (S.D.) = 58.5 (13.2) years; mean disease duration (S.D.) = 7.3 (12.0) years, completed the study. According to the group X time analysis, significant differences were found in respiratory function, mobility, and the ALSFRS-R in favor of the aerobic-strength group. These patients maintained their abilities, whereas, a significant decrease was observed in the flexibility training group. Scores of the SF-36 categories "physical functioning", "energy fatigue" and "wellbeing" were higher following the intervention in the aerobic-strength group compared with the stretching control group.

CONCLUSIONS

A 12-week combined aerobic and strength training program is far superior to flexibility alone in improving respiratory function, mobility, and wellbeing in ambulatory ALS patients.