Purpose:
This study assessed the biological reliability of peripheral human cytokines and adipokines, and the influence of participant characteristics on total error. This has essential application ...to interventional cytokine measurement to ensure that reported results are interpreted with confidence.
Methods:
Participants (49% female, 18–85 years,
n
= 84) completed two consecutive-day testing sessions. Participants provided a venous blood sample at the same time of day across two consecutive days, under standardized participant presentation, including 24-h rested and 12-h fasted conditions. Multiplex immunoassay was used to assess inflammatory analytes from samples (predominantly plasma). Repeat measurements were conducted between-day for total precision quantification, and technical (technique) error was negated from the total to provide an estimate of biological (attributed to participant presentation) error.
Results:
Whilst there was no evidence of statistically significant biological error, a small amount of biological error was consistently present across most analytes (∼3.3%/0.07 pg/ml), which was largest for measurement of leptin (7.3%/210 pg/ml). There was also an influence of sex on reliability of leptin and adiponectin (total model explained 6–7% of error variation), where females demonstrated the greatest error.
Conclusion:
Biological error reported in this study should be applied to any future study or individual with a repeated measurement of cytokine concentrations over time that maintain best practice procedures (12-h fasted, 24-h rested). In most cases, raw error should be used, with exceptions for women for measurement of leptin and adiponectin. This approach will ensure that results are reported with certainty for improved reporting of intervention efficacy.
Abstract Objectives Fluctuating endogenous and exogenous ovarian hormones may influence exercise parameters; yet control and verification of ovarian hormone status is rarely reported and limits ...current exercise science and sports medicine research. The purpose of this study was to determine the effectiveness of an individualised three-step method in identifying the mid-luteal or high hormone phase in endogenous and exogenous hormone cycles in recreationally-active women and determine hormone and demographic characteristics associated with unsuccessful classification. Design Cross-sectional study design. Methods Fifty-four recreationally-active women who were either long-term oral contraceptive users (n = 28) or experiencing regular natural menstrual cycles (n = 26) completed step-wise menstrual mapping, urinary ovulation prediction testing and venous blood sampling for serum/plasma hormone analysis on two days, six to 12 days after positive ovulation prediction to verify ovarian hormone concentrations. Results Mid-luteal phase was successfully verified in 100% of oral contraceptive users, and 70% of naturally-menstruating women. Thirty percent of participants were classified as luteal phase deficient; when excluded, the success of the method was 89%. Lower age, body fat and longer menstrual cycles were significantly associated with luteal phase deficiency. Conclusions A step-wise method including menstrual cycle mapping, urinary ovulation prediction and serum/plasma hormone measurement was effective at verifying ovarian hormone status. Additional consideration of age, body fat and cycle length enhanced identification of luteal phase deficiency in physically-active women. These findings enable the development of stricter exclusion criteria for female participants in research studies and minimise the influence of ovarian hormone variations within sports and exercise science and medicine research.
Chronic inflammation is independently associated with the incidence and progression of chronic disease. Exercise has been found to reduce chronic inflammation, however the role of exercise intensity ...(work rate) is unknown. This review aimed to determine the pooled effect of higher- compared to lower-intensity aerobic and resistance exercise on chronic inflammation in adults.
Systematic review and meta-analysis.
Five electronic databases were searched. Intervention trials that assessed the effect of ≥2 different exercise intensities on peripheral markers of chronic inflammation c-reactive protein (CRP), interleukin (IL)-6, tumour necrosis factor (TNF)-α and IL-10 in adults were included. Random-effect meta-analyses were conducted to calculate the mean difference in change scores between groups effect size (ES). Sub-group analyses were performed to explore the influence of age, chronic disease, body mass index and intervention duration on inflammation heterogeneity.
Of 3952 studies identified, 27 were included. There were no significant effects of exercise intensity on IL-6 (ES=-0.039, 95%CI=-0.353–0.275; p=0.806), TNF-α (ES=0.296, 95%CI=-0.184–0.777; p=0.227) and IL-10 (ES=0.007, 95%CI=-0.904–0.919; p=0.987). A significant pooled ES was observed for higher- versus lower-intensity exercise on CRP concentrations, in studies of middle-aged adults (ES=-0.412, 95%CI=-0.821– -0.004, p=0.048) or interventions >9 weeks in duration (ES=-0.520, 95%CI=-0.882–-0.159, p=0.005).
Exercise intensity did not influence chronic inflammatory response. However, sub-analyses suggest that higher-intensity training may be more efficacious than lower-intensity for middle-aged adults, or when longer duration interventions are implemented (>9 weeks), in the most commonly-reported analyte (CRP).
Low-grade systemic inflammation is a key driver of muscle degeneration in older adults, and diets with pro-inflammatory properties may further contribute to loss of muscle mass, strength and ...function. Therefore, this research aimed to explore the associations between the inflammatory potential of the diet and measures of sarcopenia symptomology in community-dwelling older adults. Upper (handgrip strength, HGS) and lower extremity (sit-to-stand) muscle strength, physical performance (timed-up-and-go, TUG) and appendicular skeletal muscle mass (ASM) was assessed according to the European Working Group on Sarcopenia in Older People version 2 (EWGSOP2) criteria. Multiple 24-hr dietary recalls were used to calculate the Dietary Inflammatory Index (DII), which was then used to group participants into anti- and pro-inflammatory dietary groups. Multiple linear regression investigated associations between DII, muscle strength, physical performance, and muscle quantity adjusted for age, gender, comorbidities, waist circumference and physical activity. Adults 65-85 years (n = 110, 72.1 ± 4.7 years, 76.4% female) were recruited. One participant was identified with sarcopenia, 35.2% were pre-frail, or frail. More participants with a pro-inflammatory DII score had low muscle quantity than those with anti-inflammatory DII (3.4% vs. 6.4%, x
= 4.537,
= 0.043) and DII was negatively associated with HGS (β = -0.157,
= 0.016) and ASM (β = -0.176,
= 0.002) which remained significant after adjusting for covariates. In this population, DII was associated with less favorable muscle strength, physical performance, and muscle quantity.
PURPOSEThis study aimed to determine whether 1) consumption of caffeine improves endurance cycling performance in women and 2) sex differences exist in the magnitude of the ergogenic and plasma ...responses to caffeine supplementation.
METHODSTwenty-seven (11 women and 16 men) endurance-trained cyclists and triathletes participated in this randomized, double-blind, placebo-controlled, crossover study. Participants completed an incremental exercise test to exhaustion, two familiarization trials, and two performance trials. Ninety minutes before the performance trials, participants ingested opaque capsules containing either 3 mg·kg body mass of anhydrous caffeine or a placebo. They then completed a set amount of work (75% of peak sustainable power output) in the fastest possible time. Plasma was sampled at baseline, preexercise, and postexercise for caffeine. Strict standardization and verification of diet, hydration, training volume and intensity, and contraceptive hormone phase (for women) were implemented.
RESULTSPerformance time was significantly improved after caffeine administration in women (placebo3863 ± 419 s, caffeine3757 ± 312 s; P = 0.03) and men (placebo3903 ± 341 s, caffeine3734 ± 287 s; P < 0.001). The magnitude of performance improvement was similar for women (mean = 4.3%, 95% CI = 0.4%–8.2%) and men (4.6%, 2.3%–6.8%). Plasma caffeine concentrations were similar between sexes before exercise, but significantly greater in women after exercise (P < 0.001).
CONCLUSIONSIngestion of 3 mg·kg body mass of caffeine enhanced endurance exercise performance in women. The magnitude of the performance enhancement observed in women was similar to that of men, despite significantly greater plasma caffeine concentrations after exercise in women. These results suggest that the current recommendations for caffeine intake (i.e., 3–6 mg·kg caffeine before exercise to enhance endurance performance), which are derived almost exclusively from studies on men, may also be applicable to women.
Exercise has been shown to improve physical and psychosocial outcomes for people across the cancer care continuum. A proposed mechanism underpinning the relationship between exercise and cancer ...outcomes is exercise-induced immunomodulation via secretion of anti-inflammatory myokines from skeletal muscle tissue. Myokines have the potential to impair cancer growth through modulation of natural killer (NK) cells and CD8+ T cells while improving the effectiveness of cancer therapies. Interleukin-15 (IL-15), one of the most abundant myokines found in skeletal muscle, has a key immunoregulatory role in supporting the proliferation and maturation of T cells and NK cells, which have a key role in the host's immune response to cancer. Furthermore, IL-15 is being explored clinically as an immunotherapy agent with doses similar to the IL-15 concentrations released by skeletal muscle during exercise. Here we review the role of IL-15 within the immune system, examine how IL-15 is produced as a myokine during exercise, and how it may improve outcomes for people with cancer, specifically as an adjuvant or neoadjuvant to immunotherapy. We summarize the available evidence showing changes in IL-15 in response to both acute exercise and training, and the results are inconsistent; higher quality research is needed to advance the understanding of how exercise-mediated increases in IL-15 potentially benefit those who are being treated for, or who have had, cancer.
Dementia prevention: the time to act is now Chong, Terence Wh; Macpherson, Helen; Schaumberg, Mia A ...
Medical journal of Australia,
04/2021, Letnik:
214, Številka:
7
Journal Article
Community-based exercise programs for older adults play a potentially important role in mitigating the decline in functional outcomes, body composition, psychosocial outcomes, and cardiovascular ...health outcomes that commonly occurs with advancing age. There is a limited understanding of the characteristics and effectiveness of community-based exercise programs, particularly when those programs are offered outside metropolitan areas. Rural/regional settings face unique challenges, such as limited access to equipment/resources, transportation, and services, as well as significant costs to run programs. The objective of this scoping review was to characterise studies in the field that have aimed to implement community-based programs in settings identified as rural / regional. A secondary aim was to establish guidance for future exercise programs in this setting and highlight future research directions. A total of 12 studies were conducted in settings identified as rural/regional areas in various countries across the world were included. Of the included studies, five were randomised controlled trials. The majority of included studies reported on functional outcomes (83%) and psychosocial outcomes (75%), yet only 42% reported body composition, 17% reported cardiovascular health and 17% reported dietary outcomes. Low male representation was observed, with women outnumbering men in 7 of 12 studies. There was also minimal investigation of qualitative outcomes in existing community-based exercise programs in rural/regional settings, presenting a key gap for future research to address. Study Protocol:
https://osf.io/txpm3/
. Date of registration: 20 July 2020.
Reliability of body composition measurement techniques is essential to the accurate reporting of intervention outcomes. However, the between-day precision error of commonly used techniques, as well ...as the reference multi-compartment model, in a population-representative sample are currently unknown.
To quantify technical and biological precision error of body composition techniques in comparison to the referent 4-compartment (4C) model.
Men and women (1:1 ratio; 18–85 years old; n = 90) completed 2 consecutive-day body composition testing sessions, including individual components of the referent 4C model. Testing was undertaken in accordance with best practice guidance for each technique, including standardized presentation and a consistent time of day. Repeat measurements were conducted on day 1 for technical precision, and between-day measurements were conducted for biological precision quantification.
On average, all measurements met acceptable error limits and presented typically low technical and biological error <2% fat-free mass (FFM) and < 3% fat mass (FM) precision error. For technical precision of FFM, all techniques met a priori cut points (80%; CV = 0.45–0.81%). For FM, all techniques were equivalent to the best-rating method on average (CV = 0.78–1.35%), except air displacement plethysmography (CV = 2.13%). For biological precision, only 3-compartment (3C) and 4C equations sufficiently met the a priori determined cut point for estimates for FFM (CV = 0.77–0.79%), and only DXA met the 80% cut point (CV = 1.17%) for FM.
The primary purpose of a study design is imperative when deciding on body composition assessment techniques used for longitudinal measurements. If reliable longitudinal assessments of FFM are central, a 3C or 4C model may be indicated. If FM is a primary outcome, DXA may be preferable. However, considering the low error rates presented within the current study across a broad age span of healthy adults with implementation of best-practice guidelines, any technique assessed here may be used, provided that strict protocols are adhered to.
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Clinical practice guidelines recommend that adults with type 2 diabetes (T2D) sit less and move more throughout the day. The 18-month OPTIMISE Your Health Clinical Trial was developed to support ...desk-based workers with T2D achieve these recommendations. The two-arm protocol consists of an intervention and control arms. The intervention arm receives 6 months health coaching, a sit-stand desktop workstation and an activity tracker, followed by 6 months of text message support, then 6 months maintenance. The control arm receives a delayed modified intervention after 12 months of usual care. This paper describes the methods of a randomised controlled trial (RCT) evaluating the effectiveness and cost-effectiveness of the intervention, compared to a delayed intervention control.
This is a two-arm RCT being conducted in Melbourne, Australia. Desk-based workers (≥0.8 full-time equivalent) aged 35-65 years, ambulatory, and with T2D and managed glycaemic control (6.5-10.0% HbA1c), are randomised to the multicomponent intervention (target n = 125) or delayed-intervention control (target n = 125) conditions. All intervention participants receive 6 months of tailored health coaching assisting them to "sit less" and "move more" at work and throughout the day, supported by a sit-stand desktop workstation and an activity tracker (Fitbit). Participants receive text message-based extended care for a further 6-months (6-12 months) followed by 6-months of non-contact (12-18 months: maintenance). Delayed intervention occurs at 12-18 months for the control arm. Assessments are undertaken at baseline, 3, 6, 12, 15 and 18-months. Primary outcomes are activPAL-measured sitting time (h/16 h day), glycosylated haemoglobin (HbA1c; %, mmol/mol) and, cognitive function measures (visual learning and new memory; Paired Associates Learning Total Errors adjusted). Secondary, exploratory, and process outcomes will also be collected throughout the trial.
The OPTIMISE Your Health trial will provide unique insights into the benefits of an intervention aimed at sitting less and moving more in desk-bound office workers with T2D, with outcomes relevant to glycaemic control, and to cardiometabolic and brain health. Findings will contribute new insights to add to the evidence base on initiating and maintaining behaviour change with clinical populations and inform practice in diabetes management.
ANZCTRN12618001159246 .