Sedentarism: a concept analysis

Physical exercise and COVID-19 pandemic in PubMed: Two months of dynamics and one year of original scientific production

Our aim was to conduct a narrative review about physical exercise and Corona Virus Disease 2019 (COVID-19). A literature search was completed crossing the keywords “COVID-19” and “physical exercise”, for a narrative review, and physical activity (PA), physical exercise, physical training, sport, physical fitness, for a systematic review; search strategy (Randomized Controlled Trial, in the last 1 year, English). The first search date was closed on 04/26/2020 and 06/26/2020. This strategy was chosen to assess the dynamics of scientific information production for the pandemic. In two months, an increase of 76%, from 12 (19.4%) to 50 (80.64%) COVID-19 articles (n = 62, 100%) was found. The main types of articles published were editorial articles (16.13%, n = 10 of 62 articles) and commentary (9.68%, n = 6 of 62 articles). The most frequent country of origin of the scientific production was the United States (12.90%, n = 8 of 62 articles), the United Kingdom (12.90%, n = 8 of 62 articles), and Brazil (11.29%, n = 7 of 62 articles). However, in 2020, there were only 2 relevant randomized controlled trials on the COVID-19 topic in the context of physical exercise. Scientific information production shows the concern of the PA science community to bring a solution to the increase in physical inactivity generated by the COVID-19 pandemic. Our findings show the dynamics of scientific production on the COVID-19, in a situation so unique such as a pandemic, denotes that the practice of PA is essential to improve and/or maintain physical and mental health.

Deficient muscle regeneration potential in sarcopenic COPD patients: Role of satellite cells

Sarcopenia is a major comorbidity in chronic obstructive pulmonary (COPD). Whether deficient muscle repair mechanisms and regeneration exist in the vastus lateralis (VL) of sarcopenic COPD remains debatable. In the VL of control subjects and severe COPD patients with/without sarcopenia, satellite cells (SCs) were identified (immunofluorescence, specific antibodies, anti-Pax-7, and anti-Myf-5): activated (Pax-7+/Myf-5+), quiescent/regenerative potential (Pax-7+/Myf-5-), and total SCs, nuclear activation (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling [TUNEL]), and muscle fiber type (morphometry and slow- and fast-twitch, and hybrid fibers), muscle damage (hematoxylin-eosin staining), muscle regeneration markers (Pax-7, Myf-5, myogenin, and MyoD), and myostatin levels were identified. Compared to controls, in VL of sarcopenic COPD patients, myostatin content, activated SCs, hybrid fiber proportions, TUNEL-positive cells, internal nuclei, and muscle damage significantly increased, while quadriceps muscle strength, numbers of Pax-7+/Myf-5- and slow- and fast-twitch, and hybrid myofiber areas decreased. In the VL of sarcopenic and nonsarcopenic patients, TUNEL-positive cells were greater, whereas muscle regeneration marker expression was lower than in controls. In VL of severe COPD patients regardless of the sarcopenia level, the muscle regeneration process is triggered as identified by SC activation and increased internal nuclei. Nonetheless, a lower regenerative potential along with significant alterations in muscle phenotype and damage, and increased myostatin were prominently seen in sarcopenic COPD.

Differences in micro-RNA expression profile between vastus lateralis samples and myotubes in COPD cachexia

Quadriceps muscle weakness and wasting are common comorbidities in chronic obstructive pulmonary disease (COPD). Micro-RNA expression upregulation may favor muscle mass growth and differentiation. We hypothesized that the profile of muscle-enriched micro-RNAs in cultured myotubes differs between patients with COPD of a wide range of body composition and healthy controls and that expression levels of those micro-RNAs from patients with COPD and controls differ between in vivo and in vitro conditions. Twenty-nine patients with COPD [ n = 15 with muscle wasting and fat-free mass index (FFMI) 15 kg/m² and n = 14 with normal body composition and FFMI 18 kg/m²] and 10 healthy controls (FFMI 19 kg/m²) were consecutively recruited. Biopsies from the vastus lateralis muscle were obtained in all study subjects. A fragment of each biopsy was used to obtain primary cultures, in which muscle cells were first proliferated to be then differentiated into actual myotubes. In both sets of experiments (in vivo biopsies and in vitro myotubes) the following muscle-enriched micro-RNAs from all the study subjects were analyzed using quantitative real-time PCR amplification: micro-RNA (miR)-1, miR-133a, miR-206, miR-486, miR-29b, miR-27a, and miR-181a. Whereas the expression of miR-1, miR-206, miR-486, and miR-29b was upregulated in the muscle biopsies of patients with COPD compared with those of healthy controls, levels of none of the studied micro-RNAs in the myotubes (primary cultured cells) significantly differed between patients with COPD and the controls. We conclude from these findings that environmental factors (blood flow, muscle metabolism, and inflammation) taking place in vivo (biopsies) in muscles may account for the differences observed in micro-RNA expression between patients with COPD and controls. In the myotubes, however, the expression of the same micro-RNAs did not differ between the study subjects as such environmental factors were not present. These findings suggest that therapeutic strategies should rather target environmental factors in COPD muscle wasting as the profile of micro-RNA expression in myotubes was similar in patients to that observed in the healthy controls. NEW & NOTEWORTHY Environmental factors taking place in vivo (biopsies) in the muscles may explain differences observed in micro-RNA expression between patients with chronic obstructive pulmonary disease (COPD) and controls. In the myotubes, however, the expression of the same micro-RNAs did not differ between the study subjects as such environmental factors were not present. These findings suggest that therapeutic strategies should rather target environmental factors in COPD muscle wasting and cachexia as micro-RNA expression profile in myotubes was similar between patients and controls.

The phosphodiesterase-4 inhibitor roflumilast reverts proteolysis in skeletal muscle cells of patients with COPD cachexia

Peripheral muscle weakness and mass loss are characteristic features in severe chronic obstructive pulmonary disease (COPD). We hypothesized that the phosphodiesterase (PDE)-4 inhibitor roflumilast-induced cAMP may ameliorate proteolysis and metabolism in skeletal muscles of COPD patients with severe muscle wasting. In myogenic precursor cells (isolated from muscle biopsies and cultured up to obtain differentiated myotubes) from 10 severe COPD patients and 10 healthy controls, which were treated with 1 μM roflumilast N-oxide (RNO) for three time cohorts (1, 6, and 24 h), genes of antioxidant defense and oxidative stress marker, myogenesis and muscle metabolism, proteolysis (tyrosine release assay) and ubiquitin-proteasome system markers, autophagy, and myosin isoforms were analyzed using RT-PCR and immunoblotting. In COPD patients at 6 h RNO treatment, myotube tyrosine release, total protein ubiquitination, and tripartite motif-containing protein 32 levels were significantly lower than healthy controls, whereas at 24 h RNO treatment, myotube myosin heavy chain ( MyHC) -I and MyHC-IIx expression levels were upregulated in both patients and controls. In the 6-h RNO cohort, in patients and controls, myotube expression of nuclear factor (erythroid-derived 2)-like 2 ( NRF2) and its downstream antioxidants sirtuin-1, FGF-inducible 14, and insulin-like growth factor-1 was upregulated, whereas that of myocyte-specific enhancer factor 2C, myogenic differentiation, myogenin, myostatin, atrogin-1, and muscle RING-finger protein-1 was downregulated. In myotubes of severe COPD patients with cachexia, roflumilast-induced cAMP signaling exerts beneficial effects by targeting muscle protein breakdown (tyrosine release), along with reduced expression of proteolytic markers of the ubiquitin-proteasome system and that of myostatin. In both patients and controls, roflumilast also favored antioxidant defense through upregulation of the NRF2 pathway and that of the histone deacetylase sirtuin-1, whereas it improved the expression of slow- and fast-twitch myosin isoforms. These findings show that muscle dysfunction and wasting may be targeted by roflumilast-induced cAMP signaling in COPD. These results have potential therapeutic implications, as this PDE-4 inhibitor is currently available for the treatment of systemic inflammation and exacerbations in patients with severe COPD. NEW & NOTEWORTHY In myotubes of cachectic chronic obstructive pulmonary disease (COPD) patients, cAMP signaling exerted beneficial effects by targeting muscle proteolysis and reducing gene expression of proteolytic markers of the ubiquitin-proteasome system and that of myostatin. In myotubes of patients and controls, roflumilast also favored antioxidant defense through upregulation of the nuclear factor (erythroid-derived 2)-like 2 pathway, of sirtuin-1, and of gene expression of slow- and fast-twitch isoforms. These findings have potential clinical implications for the treatment of muscle wasting in patients with COPD and cachexia.

Efficacy of high-intensity, low-volume interval training compared to continuous aerobic training on insulin resistance, skeletal muscle structure and function in adults with metabolic syndrome: study protocol for a randomized controlled clinical trial (Intraining-MET)

Background

Evidence of the efficacy of high-intensity, low-volume interval training (HIIT-low volume) in treating insulin resistance (IR) in patients with metabolic disorders is contradictory. In addition, it is unknown whether this effect is mediated through muscle endocrine function, which in turn depends on muscle mass and fiber type composition. Our aims were to assess the efficacy of HIIT-low volume compared to continuous aerobic exercise (CAE) in treating IR in adults with metabolic syndrome (MS) and to establish whether musclin, apelin, muscle mass and muscle composition are mediators of the effect.

Methods

This is a controlled, randomized, clinical trial using the minimization method, with blinding of those who will evaluate the outcomes and two parallel groups for the purpose of showing superiority. Sixty patients with MS and IR with ages between 40 and 60 years will be included. A clinical evaluation will be carried out, along with laboratory tests to evaluate IR (homeostatic model assessment (HOMA)), muscle endocrine function (serum levels of musclin and apelin), thigh muscle mass (by dual energy x-ray absorptiometry (DXA) and thigh muscle composition (by carnosine measurement with proton magnetic resonance spectroscopy (¹H–MRS)), before and after 12 weeks of a treadmill exercise program three times a week. Participants assigned to the intervention (n = 30) will receive HIIT-low volume in 22-min sessions that will include six intervals at a load of 90% of maximum oxygen consumption (VO₂ max) for 1 min followed by 2 min at 50% of VO₂ max. The control group (n = 30) will receive CAE at an intensity of 60% of VO₂ max for 36 min. A theoretical model based on structural equations will be proposed to estimate the total, direct and indirect effects of training on IR and the proportion explained by the mediators.

Discussion

Compared with CAE, HIIT-low volume can be effective and efficient at improving physical capacity and decreasing cardiovascular risk factors, such as IR, in patients with metabolic disorders. Studies that evaluate mediating variables of the effect of HIIT-low volume on IR, such as endocrine function and skeletal muscle structure, are necessary to understand the role of skeletal muscle in the pathophysiology of MS and their regulation by exercise.

Trial registration

NCT03087721. High-intensity Interval, Low Volume Training in Metabolic Syndrome (Intraining-MET). Registered on 22 March 2017, retrospectively registered.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2541-7) contains supplementary material, which is available to authorized users.

Relationship between dual task walking, cognition, and depression in oldest old people

BACKGROUND

The purpose of the study was to investigate the relationship between dual task walking, cognition, and depression in oldest old people living in the community.

METHODS

We conducted an observational cross-sectional study at Federal University of São Carlos (Brazil). We assessed 67 community-dwelling older adults aged 80 years and over, who were able to walk alone and did not present with a risk of dementia (assessed by Mini-Mental State Examination, MMSE). The assessment consisted of anamnesis, dual task using the Timed Up and Go test associated with a motor task (TUGT-motor) and a cognitive task (TUGT-cognitive); cognitive measures using MMSE, Montreal Cognitive Assessment (MoCA), Clock Drawing test (CDT) and verbal fluency, and depressive measures by the Geriatric Depression Scale (GDS).

RESULTS

There was a correlation with higher magnitude between cognitive tests and TUGT-cognitive, compared to TUGT-motor. For TUGT-motor, the highest correlations with cognitive tests were found between time and MMSE, MoCA (total score), and MoCA visuospatial/executive domain. For TUGT-cognitive, the highest correlations with cognitive tests were between number of steps and MMSE and between time and MMSE. GDS showed a significant weak correlation with number of steps taken in TUGT-motor, wrong words, and correct/time of TUGT-cognitive.

CONCLUSIONS

Dual task performances are associated with cognition in oldest old. Furthermore, dual task tests have less influence of educational level, are functional, fast, and easily applicable in clinical practice. Future studies are needed to confirm if dual task test is useful for cognitive screening in oldest old.

A case control study investigating the effects of levels of physical activity at work as a risk factor for prostate cancer

BACKGROUND

A potential risk factor for prostate cancer is occupational physical activity. The occupational aetiology of prostate cancer remains unclear. The purpose of this research was to examine associations between the level of exposure to various measures of physical activity at work and the risk of Prostate Cancer.

METHODS

Using the Finnish Job Exposure Matrix and the occupational history of 1,436 cases and 1,349 matched controls from an Australian case control study; we investigated five related exposure variables considered to be risk factors by comparing odds ratios.

RESULTS

Modestly increasing odds ratios were detected with increasing levels of workload but there was no difference in this trend between moderate and high grade tumours. In regard to occupational physical workload no statistically significant association was observed overall but an increasing trend with level of exposure was observed for high grade compared with moderate grade tumours.

CONCLUSION

Both workload and physical workload merit further investigation, particularly for the latter in relation to grade of tumour.

Sedentarism: the effects of Internet use on human obesity in the United States

This paper analyzes the impact of Internet use on human obesity in the United States. The United States is facing a skyrocketing obesity epidemic among adults and children. The authors hypothesize that the more individuals use the Internet, the more they increase their risks of becoming obese. The explanation is that Internet use may cause sedentarism, which refers to decreased energy expenditure or, simply, physical inactivity. Sedentarism, in turn, may increase obesity.

Dietary attitudes and diseases of comfort

This article reviews Western dietary attitudes and lifestyle choices by identifying the environmental, social and personal factors that determine said attitudes and choices. Environmental factors exert a major influence on, and complicate, dietary behavior, primarily by facilitating the consumption of meals away from home and by minimizing time dedicated to meal preparation and consumption. Social factors, from mass media to advertising and cultural traditions, also influence food intake, to an extent that is still underestimated. Ignorance of the real influence of environment and society on food choices could well blind consumers to the real significance of such choices. Accordingly, this review discusses differing aspects of emerging dietary trends and/or philosophies, and underlines their potentially harmful influence on health. Western countries are increasingly witnessing a dichotomy between the findings of nutritional science and the choices that dietary trends propose and impose. Coinciding with the obesity epidemic and the spread of other food-related diseases, this dichotomy calls for the development of effective preventive strategies.

Physical activity as primary prevention to address cancer disparities

OBJECTIVE

To review the research literature on physical activity (PA) intervention trials, with an emphasis on underserved populations.

DATA SOURCE

Research studies, review articles, and books.

CONCLUSION

PA intervention studies have generally shown statistically significant but modest outcomes. Comprehensive intervention designs combining individual-level and physical environmental changes have posted the largest effect sizes, and emerging models are incorporating sociocultural and organizational environmental changes with promising results. Research including or targeting underserved populations poses unique challenges at each stage of the intervention process: design, recruitment, implementation, and evaluation. Synthesis of evidence-based approaches to address these challenges is presented.

IMPLICATIONS FOR NURSING PRACTICE

Promoting PA in underserved communities is essential in improving population-level cancer outcomes. Additional resources are becoming available to nursing researchers and practitioners to aid in the conduct of PA intervention in understudied groups.