Salivary testosterone and immunoglobulin A were increased by resistance training in adults with Down syndrome

Impact of exercise on markers of B cell-related immunity: A systematic review

BACKGROUND

B cells represent a crucial component of adaptive immunity that ensures long-term protection from infection by generating pathogen-specific immunoglobulins. Exercise alters B cell counts and immunoglobulin levels, but evidence-based conclusions on potential benefits for adaptive immunity are lacking. This systematic review assessed current literatures on the impact of acute exercise and exercise training on B cells, immunoglobulins, and markers of secretory immunity in human biofluids.

METHODS

According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, MEDLINE, Web of Science, and Embase were searched on March 8, 2023. Non-randomized controlled trials and crossover trials investigating the impact of acute exercise or exercise training on B cell counts and proportions, immunoglobulin levels, salivary flow rate, or secretory immunoglobulin A secretion rate were included. Quality and reporting of exercise training studies were assessed using the Tool for the Assessment of Study Quality and reporting in Exercise. Study characteristics, outcome measures, and statistically significant changes were summarized tabularly.

RESULTS

Of the 67 eligible studies, 22 applied acute exercise and 45 applied exercise training. All included outcomes revealed significant alterations over time in acute exercise and exercise training context, but only a few investigations showed significant differences compared to control conditions. Secretory and plasma immunoglobulin A levels were most consistently increased in response to exercise training.

CONCLUSION

B cell-related outcomes are altered by acute exercise and exercise training, but evidence-based conclusions cannot be drawn with high confidence due to the large heterogeneity in populations and exercise modalities. Well-designed trials with large sample sizes are needed to clarify how exercise shapes B cell-related immunity.

Immunological Response to Exercise in Athletes with Disabilities: A Narrative Review of the Literature

For a person with a disability, participating in sports activities and/or competitions can be a challenge for the immune system. The relationship between exercise and immunity response in disabled athletes is, indeed, extremely complex for several reasons, including (1) the chronic low-grade inflammatory and immunodepression-"secondary immune deficiency"-state imposed by the disability/impairment; (2) the impact of the disability on an array of variables, spanning from physical fitness to well-being, quality of life, sleep, and nutritional aspects, among others, which are known to mediate/modulate the effects of exercise on human health; (3) the variability of the parameters related to the exercise/physical activity (modality, frequency, intensity, duration, training versus competition, etc.); and (4) the intra- and inter-individual variability of the immunological response to exercise. In able-bodied athletes, previously published data described several exercise-induced changes affecting various immunological subsets and subpopulations, ranging from neutrophils to lymphocytes, and monocytes. Broadly, moderate intensity workout is accompanied by optimal immunity and resistance to infections such as upper respiratory tract infections (URTI) in athletes. Periods of intense training with insufficient recovery can cause a temporary state of immunosuppression, which should end with a few days of rest/recovery from exercise. Disabled athletes are relatively overlooked and understudied with respect to their able-bodied counterparts. Findings from the few studies available on paralympic and disabled athletes are here summarized and analyzed utilizing a narrative approach to review and determine the major features of the immunological and inflammatory responses to exercise in this specific population. Moreover, a few studies have reported behavioral, dietary, and training strategies that can be adopted to limit exercise-induced immunosuppression and reduce the risk of infection in people with disabilities. However, given the paucity of data and contrasting findings, future high-quality investigations on paralympic and disabled athletes are urgently needed.

Health Outcomes of Physical Activity Interventions in Adults With Down Syndrome: A Systematic Review

This systematic review examined whether physical activity interventions improve health outcomes in adults with Down syndrome (DS). We searched PubMed, APA PsycInfo, SPORTDiscus, APA PsycARTICLES, and Psychology and Behavioral Sciences Collection using keywords related to DS and physical activity. We included 35 studies published in English since January 1, 1990. Modes of exercise training programs included aerobic exercise, strength training, combined aerobic and strength training, aquatic, sport and gaming, and aerobic and strength exercise interventions combined with health education. The evidence base indicates that aerobic and strength exercise training improve physical fitness variables including maximal oxygen uptake, maximal heart rate, upper and lower body strength, body weight, and body fat percentage. Sport and gaming interventions improve functional mobility, work task performance, and sport skill performance. We concluded that adults with DS can accrue health benefits from properly designed physical activity and exercise interventions.

Resistance training and Down Syndrome: A narrative review on considerations for exercise prescription and safety

The current manuscript reviews the literature on the health effects of resistance training (RT) for individuals with Down syndrome (DS), focusing on this training modality’s methodology, application, and safety. The literature has mentioned that early aging in this population is associated with loss of muscle strength, lower lean and bone mass, and increased obesity. It is necessary to propose non-pharmacological measures for prevention and health promotion. Thus, this review suggests a current research-based RT guide for individuals with DS. This review is divided into three sections: Section 2 briefly reviews DS and the effects on structural and functional decline and how exercise and physical activity can influence health aspects in this population; Section 3 summarizes the evidence for RT prescription; Section 4 briefly reviews the health and potential benefits of RT in individuals with DS. The findings from this review suggest that most individuals with DS should engage in moderate-intensity RT at least 2 days a week and perform RT on the major muscle groups and include balance training. The RT program should be modified and adapted according to individuals’ characteristics and limitations. RT promotes positive, health-related benefits such as increasing strength, improving body composition, improving functional capacity and balance, reducing inflammatory status and oxidative stress, and improving the immune system. The RT protocols summarized in this current review provide guidance, critical conclusions, and novel research settings, which could be useful to coaches, clinicians, and researchers to effectively design RT program for individuals with DS.

Prescription and Effects of Strength Training in Individuals with Intellectual Disability-A Systematic Review

The practice of physical exercise (PE), especially strength training (ST), has health benefits in the healthy population; however, the literature is scarce in the recommendations related to the population with intellectual disability (ID). This study represents the first analysis on the topic and aims to examine the structure and efficacy of ST experimental intervention programs in individuals with ID. This systematic review was carried out between January and April 2021, using the PubMed, Web of Science, Scopus, and SPORTDiscus databases, according to the PRISMA guidelines. From a total of 166 studies, eight were included in the present systematic review. The studies included a total of 280 individuals (18.23 ± 2.86 years old). The main features of the exercise programs are: 12 weeks average duration, three weekly sessions of 45–60 min, six to seven exercises targeting the main muscle groups, two to three sets, 6–12 repetitions, and avoiding free weights for safety reasons. The main results showed increments in strength, balance and fat-free mass and decrements in fat mass and waist circumference. It is a useful guideline for PE technicians to prescribe and adjust correctly in order to not only promote physical fitness, but improve the quality of life of individuals with ID.

Effects of Regular Physical Activity on the Immune System, Vaccination and Risk of Community-Acquired Infectious Disease in the General Population: Systematic Review and Meta-Analysis

Background

Regular physical activity is the prime modality for the prevention of numerous non-communicable diseases and has also been advocated for resilience against COVID-19 and other infectious diseases. However, there is currently no systematic and quantitative evidence synthesis of the association between physical activity and the strength of the immune system.

Objective

To examine the association between habitual physical activity and (1) the risk of community-acquired infectious disease, (2) laboratory‐assessed immune parameters, and (3) immune response to vaccination.

Methods

We conducted a systemic review and meta-analysis according to PRISMA guidelines. We searched seven databases (MEDLINE, Embase, Cochrane CENTRAL, Web of Science, CINAHL, PsycINFO, and SportDiscus) up to April 2020 for randomised controlled trials and prospective observational studies were included if they compared groups of adults with different levels of physical activity and reported immune system cell count, the concentration of antibody, risk of clinically diagnosed infections, risk of hospitalisation and mortality due to infectious disease. Studies involving elite athletes were excluded. The quality of the selected studies was critically examined following the Cochrane guidelines using ROB2 and ROBINS_E. Data were pooled using an inverse variance random-effects model.

Results

Higher level of habitual physical activity is associated with a 31% risk reduction (hazard ratio 0.69, 95% CI 0.61–0.78, 6 studies, N = 557,487 individuals) of community-acquired infectious disease and 37% risk reduction (hazard ratio 0.64, 95% CI 0.59–0.70, 4 studies, N = 422,813 individuals) of infectious disease mortality. Physical activity interventions resulted in increased CD4 cell counts (32 cells/µL, 95% CI 7–56 cells/µL, 24 studies, N = 1112 individuals) and salivary immunoglobulin IgA concentration (standardised mean difference 0.756, 95% CI 0.146–1.365, 7 studies, N = 435 individuals) and decreased neutrophil counts (704 cells/µL, 95% CI 68–1340, 6 studies, N = 704 individuals) compared to controls. Antibody concentration after vaccination is higher with an adjunct physical activity programme (standardised mean difference 0.142, 95% CI 0.021–0.262, 6 studies, N = 497 individuals).

Conclusion

Regular, moderate to vigorous physical activity is associated with reduced risk of community-acquired infectious diseases and infectious disease mortality, enhances the first line of defence of the immune system, and increases the potency of vaccination.

Protocol registration

The original protocol was prospectively registered with PROSPERO (CRD42020178825).

Supplementary Information

The online version contains supplementary material available at 10.1007/s40279-021-01466-1.

Effects of resistance training interventions on muscular strength in adults with intellectual disability: a systematic review and meta-analysis

PURPOSE

Muscular strength is critical for adults with an intellectual disability (ID) to promote their mobility, cardiovascular capacity, and performance of daily living/recreational/vocational activities. This article reports the results of the first systematic review and meta-analysis of peer-reviewed clinical trials that evaluated the effects of resistance training (RT) interventions on muscular strength in adults with ID.

METHODS

The protocol was registered with PROSPERO (CRD42020184905). The review focuses on clinical trials that recorded quantitative measures of maximum muscular strength. Eleven electronic databases were searched from their earliest available record up to May 2020. After screening 1996 search records, 11 clinical trials were reviewed.

RESULTS

The RT interventions, while heterogeneous, had an overall significant (p ≤ 0.05) effect on muscular strength in adults with ID, ages 25-58 years. The findings were more significant and less heterogeneous for non-combined RT interventions than for interventions that combined RT exercises with aerobic or balance exercises. The TESTEX overall score was 8.3 ± 3.6.

CONCLUSIONS

RT interventions (particularly when not combined with other exercises) are effective in promoting muscular strength in adults with ID. The limited number of studies and the low study quality scores indicate a potential risk of bias, which limits the interpretation of the findings and warrants further investigation.IMPLICATIONS FOR REHABILITATIONMuscular strength is critical for adults with an intellectual disability (ID) to promote their mobility, cardiovascular capacity, and performance of daily living/recreational/vocational activities.RT interventions are an effective means of improving muscular strength in adults with ID, especially when not combined with other forms of exercise.Testing and assessment protocols used in RT programs should be individualized for adults with ID to accommodate their characteristics and should be implemented under conditions similar to those experienced during the training regimen.It is important to implement familiarization sessions before carrying out muscular strength testing or initiating an RT program to ensure safety, accuracy, and effectiveness of the program for adults with ID.

Salivary IgA as a Useful Biomarker for Dental Caries in Down's Syndrome Patients: A Systematic Review and Meta-analysis

The objective of this systematic review and meta-analysis is to critically analyze and summarize studies reporting association of salivary immunoglobulin A (IgA) levels as a biomarker for dental caries in Down syndrome (DS) patients. Using the keywords salivary [All Fields] AND IgA [All Fields] AND ("down syndrome" [MeSH Terms] OR ("down"[All Fields] AND "syndrome" [All Fields]) OR "down syndrome" [All Fields]), an electronic search was conducted via PubMed and Scopus databases by two authors, H. H. and Z. K. independently. Retrieved studies were screened against the predefined exclusion and inclusion criteria. To estimate the risk of bias, quality assessment of included studies was carried using the Newcastle-Ottawa quality assessment scale for observational studies. Primary search resulted in 10 articles from PubMed and 13 articles from Scopus. Ten studies fulfilled the defined selection criteria and evaluated the salivary IgA (sIgA) level in DS patients with dental caries. Five articles were further analyzed in a quantitative synthesis presented in the meta-analysis. Due to a modified lifestyle and compromised oral hygiene in DS patients, understandably, it is still postulated in the literature that the presence of sIgA can have a protective effect on the occurrence of dental caries as compared with healthy counterparts. As indicated by the present meta-analysis, no conclusions can be drawn as to definitively label sIgA as a biomarker for dental caries. Further, well-designed longitudinal clinical studies and translational research are therefore required before the benchmarking of sIgA as a useful biomarker for dental caries in DS patients with preferable molecular insights.

Testosterone, cortisol, and secretory immunoglobulin-A within a single day and across two sequential days among trans- and cis-gender men

BACKGROUND

Previous research on the association between testosterone (T) and immunity has produced conflicting results.

OBJECTIVES

We address two potential reasons for these empirical inconsistencies in the present research. First, the association between T and immunity may depend on which branch of the immune system is considered. Here, we examine secretory IgA (sIgA), a measure of mucosal immunity functionally related to respiratory infection risk. Second, the association between T and immunity may depend on a third regulatory variable. Therefore, we examine the interaction between T and cortisol (CORT) as well as their independent and combined effects on mucosal immunity. To do this, we explore intra-individual associations between sIgA, CORT, and T within a single day (i.e., morning vs. evening) and across 2 sequential mornings. We target two samples of men: (1) cisgender (i.e., born and identifying as men), and (2) transgender (i.e., born female but identifying as men) undergoing T therapy for gender realignment.

MATERIALS AND METHODS

One hundred and forty-eight adult men (transgender n = 29) provided saliva samples at three time points: (1) upon waking, (2) before sleep on the same day, and (3) upon waking the following day. Samples were assayed in duplicate for sIgA, T and CORT.

RESULTS

For cisgender men, sIgA, T, and CORT exhibited clear circadian rhythms and were significantly related within and between samples. For transgender men, evidence for circadian change was found for sIgA and CORT, but not T. Further, sIgA was associated with CORT, but not T.

DISCUSSION AND CONCLUSIONS

This study provides the first evidence that salivary T and sIgA concentrations are associated within a single day and across sequential days for cisgender men. Differences between cis- and transgender men suggest that this may only be true for T levels driven by endogenous production; however, future studies should employ a larger sample size.

Testosterone is positively and estradiol negatively associated with mucosal immunity in Amazonian adolescents

OBJECTIVES

A core assumption of life history theory and the immunocompetence handicap hypothesis (ICHH) is that testosterone (T) upregulates energetic investment in mating effort at the expense of immunity. This tenet, along with observed positive relationships between estrogens and immunity, may contribute to the higher observed morbidity and mortality of males. In the present study, we examine the association between sex steroid hormones and mucosal immunity as well as sex differences in immunity in a rural Amazonian population of immune-challenged Bolivian adolescents.

METHODS

Salivary steroid hormones (T [males only] and estradiol [E₂ , females only]), Tsimane-specific age-standardized BMI z-scores, and salivary mucosal immunity (sIgA, secretory IgA) were measured in 89 adolescent males and females.

RESULTS

Males had significantly higher sIgA levels than females, which may be due to the observed immune-endocrine associations found in the present study. Controlling for age and phenotypic condition, higher T significantly predicted higher sIgA; whereas higher E₂ was associated with lower sIgA in females.

CONCLUSIONS

Results stood in contrast to common interpretations of the ICHH, that is, that T should be inversely associated with immunity. Findings from the present study support the notion that the endocrine system likely affects immunity in a regulatory fashion, upregulating certain aspects of immunity while downregulating others. An important remaining question is the adaptive reason(s) for sex differences in endocrine-mediated immuno-redistribution.

Psychological effects of exercise on community-dwelling older adults

Background

In recent years, there have been an increasing number of older adults who suffer from mental disorders globally.

Objective

The objective of this study was to examine the effect of an intervention that consisted of an exercise program to improve the mental health of community-dwelling older adults.

Participants and methods

The recruited participants of this study were community-dwelling older adults aged ≥60 years who participated in a comprehensive health promotion program in Kakogawa, Japan. Participants in the intervention group received an exercise program that was developed for older adults using Thera-Band. To measure participants’ mental health status, a Japanese version of the short form of the Profile of Mood States (POMS-SF) was used. Stress markers were measured, such as salivary cortisol, alpha-amylase, and sIgA levels. All participants provided salivary samples and completed psychological questionnaires at baseline and 6-month follow-up.

Results

No significant differences were observed between the intervention and control groups with respect to POMS-SF score and salivary biomarker profile at baseline. After the intervention, the intervention group showed a significant decrease in the POMS-SF “fatigue” score and cortisol level. No significant changes were observed in the control group.

Conclusion

Simultaneous changes in feelings of fatigue and cortisol levels were observed among subjects who had received the intervention of regular exercise. Further research is needed to investigate the effectiveness of exercise intervention in improving mental health among older adults.

A systematic review of the methodological and practical challenges of undertaking randomised-controlled trials with cognitive disability populations

Approximately 10% of the world's population have a cognitive disability. Cognitive disabilities can have a profound impact on a person's social, cognitive or mental functioning, requiring high levels of costly health and social support. Therefore, it is imperative that interventions and services received are based upon a sound evidence-base. For many interventions for this population, this evidence-base does not yet exist and there is a need for more Randomised Controlled Trials (RCTs). The process of conducting RCTs with disabled populations is fraught with methodological challenges. We need a better understanding of these methodological barriers if the evidence-bases are to be developed. The purpose of this study was to explore the methodological and practical barriers to conducting trials with adults with cognitive disabilities. As a case example, the literature regarding RCTs for people with intellectual disabilities (ID) was used to highlight these pertinent issues. A systematic literature review was conducted of RCTs with adults with ID, published from 2000 to 2017. A total of 53 papers met the inclusion criteria and were reviewed. Some of the barriers reported were specific to the RCT methodology and others specific to people with disabilities. Notable barriers included; difficulties recruiting; obtaining consent; resistance to the use of control groups; engaging with carers, staff and stakeholders; the need to adapt interventions and resources to be disability-accessible; and staff turnover. Conducting RCTs with people with cognitive disabilities can be challenging, however with reasonable adjustments, many of these barriers can be overcome. Researchers are not maximising the sharing of their experience-base. As a result, the development of evidence-bases remains slow and the health inequities of people with disabilities will continue to grow. The importance of the MRC guidelines on process evaluations, together with implications for the dissemination of 'evidence-base' and 'experience-base' are discussed.