A systematic risk assessment and meta-analysis on the use of oral β-alanine supplementation.

β-Alanine supplementation is one of the world's most commonly used sports supplements, and its use as a nutritional strategy in other populations is ever-increasing, due to evidence of pleiotropic ergogenic and therapeutic benefits. Despite its widespread use, there is only limited understanding of potential adverse effects. To address this, a systematic risk assessment and meta-analysis was undertaken. Four databases were searched using keywords and Medical Subject Headings. All human and animal studies that investigated an isolated, oral, β-alanine supplementation strategy were included. Data were extracted according to 5 main outcomes, including 1) side effects reported during longitudinal trials, 2) side effects reported during acute trials, 3) effect of supplementation on circulating health-related biomarkers, 4) effect of supplementation on skeletal muscle taurine and histidine concentration, and 5) outcomes from animal trials. Quality of evidence for outcomes was ascertained using the Grading of Recommendations Assessment Development and Evaluation (GRADE) framework, and all quantitative data were meta-analyzed using multilevel models grounded in Bayesian principles. In total, 101 human and 50 animal studies were included. Paraesthesia was the only reported side effect and had an estimated OR of 8.9 [95% credible interval (CrI): 2.2, 32.6] with supplementation relative to placebo. Participants in active treatment groups experienced similar dropout rates to those receiving the placebo treatment. β-Alanine supplementation caused a small increase in circulating alanine aminotransferase concentration (effect size, ES: 0.274, CrI: 0.04, 0.527), although mean data remained well within clinical reference ranges. Meta-analysis of human data showed no main effect of β-alanine supplementation on skeletal muscle taurine (ES: 0.156; 95% CrI: −0.38, 0.72) or histidine (ES: −0.15; 95% CrI: −0.64, 0.33) concentration. A main effect of β-alanine supplementation on taurine concentration was reported for murine models, but only when the daily dose was ≥3% β-alanine in drinking water. The results of this review indicate that β-alanine supplementation within the doses used in the available research designs, does not adversely affect those consuming it

Self-reported training variables are poor predictors of laboratory measures in cyclists.

Purpose: Cycling is an activity that depends on a range of physiological attributes, as well as genetic, dietary, lifestyle and training factors. The aim of this study was to determine what self-reported training-related factors (e.g. intensity, frequency, supervision, etc) might predict laboratory-measured physiological and performance characteristics of a heterogeneous group of male and female self-classified cyclists. Methods: Forty-eight male and fourteen female cyclists completed all aspects of the study including a training questionnaire, incremental cycling test to determine maximal oxygen uptake (VO2max), 30-s Wingate test and a 4-km cycling time-trial. Principle component analysis and LASSO regression modelling were used to analyse laboratory-measures and training variables and the predictive capacity of the latter. Results: Total distance covered across all intensities was the only training variable included in most bootstrap models (63.8%), although the actual contribution was very low with a median f2 effect size equal to 0.01. Self-reported classification of cycling level was weakly correlated to guideline classification of relative VO2max in men (r=0.396, p=0.004), but not women (r=0.024, p=0.925). Conclusions: Self-reported training variables were poor predictors of laboratory-based physiological and performance variables in this heterogeneous group of cyclists. Total distance covered was the only training variable included in most regression models, but the predictive capability of outcomes was low. This suggests that most of these self-report variables are not useful pre-screening tools for categorising non-elite cyclists or raises the potential that non-elite cyclists cannot accurately quantify their own training intensities. Researchers and coaches should be wary that self-reported classification may not directly reflect the level of the cyclist

Acute cardiometabolic effects of brief active breaks in sitting for patients with rheumatoid arthritis

Exercise is a treatment in rheumatoid arthritis, but participation in moderate-to-vigorous exercise is challenging for some patients. Light-intensity breaks in sitting could be a promising alternative. We compared the acute effects of active breaks in sitting with those of moderate-to-vigorous exercise on cardiometabolic risk markers in patients with rheumatoid arthritis. In a crossover fashion, 15 women with rheumatoid arthritis underwent three 8-h experimental conditions: prolonged sitting (SIT), 30-min bout of moderate-to-vigorous exercise followed by prolonged sitting (EX), and 3-min bouts of light-intensity walking every 30 min of sitting (BR). Postprandial glucose, insulin, c-peptide, triglycerides, cytokines, lipid classes/subclasses (lipidomics), and blood pressure responses were assessed. Muscle biopsies were collected following each session to assess targeted proteins/genes. Glucose [−28% in area under the curve (AUC), P = 0.036], insulin (−28% in AUC, P = 0.016), and c-peptide (−27% in AUC, P = 0.006) postprandial responses were attenuated in BR versus SIT, whereas only c-peptide was lower in EX versus SIT (−20% in AUC, P = 0.002). IL-1β decreased during BR, but increased during EX and SIT (P = 0.027 and P = 0.085, respectively). IL-1ra was increased during EX versus BR (P = 0.002). TNF-α concentrations decreased during BR versus EX (P = 0.022). EX, but not BR, reduced systolic blood pressure (P = 0.013). Lipidomic analysis showed that 7 of 36 lipid classes/subclasses were significantly different between conditions, with greater changes being observed in EX. No differences were observed for protein/gene expression. Brief active breaks in sitting can offset markers of cardiometabolic disturbance, which may be particularly useful for patients who may find it difficult to adhere to exercise. NEW & NOTEWORTHY Exercise is a treatment in rheumatoid arthritis but is challenging for some patients. Light-intensity breaks in sitting could be a promising alternative. Our findings show beneficial, but differential, cardiometabolic effects of active breaks in sitting and exercise in patients with rheumatoid arthritis. Breaks in sitting mainly improved glycemic and inflammatory markers, whereas exercise improved lipidomic and hypotensive responses. Breaks in sitting show promise in offsetting aspects of cardiometabolic disturbance associated with prolonged sitting in rheumatoid arthritis

Physical activity: a strategy to improve antibody response to a SARS-CoV-2 vaccine booster dose in patients with autoimmune rheumatic diseases.

Physical activity associates with improved immunogenicity following a 2-dose schedule of CoronaVac (Sinovac's inactivated SARS-CoV-2 vaccine) in patients with autoimmune rheumatic diseases (ARD). This study evaluates whether physical activity impacts vaccine-induced antibody responses to a booster dose in this population. This was a phase-4 trial conducted in Sao Paulo, Brazil. Patients with ARD underwent a 3-dose schedule of CoronaVac. One month after the booster, we assessed seroconversion rates of anti-SARS-CoV-2 S1/S2 IgG, geometric mean titers of anti-S1/S2 IgG, frequency of positive neutralizing antibodies, and neutralizing activity. Physical activity was assessed through questionnaire. Physically active (n = 362) and inactive (n = 278) patients were comparable for most characteristics; however, physically active patients were younger (P<.01) and had a lower frequency of chronic inflammatory arthritis (P<.01). Adjusted models showed that physically active patients had -2 times odds of seroconversion rates (OR: 2.09; 95% confidence interval, 1.22 to 3.61), -22% greater geometric mean titers of anti-S1/S2 IgG (22.09%; 95% confidence interval, 3.91 to 65.60), and -7% greater neutralizing activity (6.76%; 95% confidence interval, 2.80 to 10.72) than inactive patients. Patients with ARD who are physically active have greater odds of experiencing better immunogenicity to a booster dose of CoronaVac. These results support the recommendation of physical activity to improve vaccination responses, particularly for immunocompromised individuals

No associations between physical activity and immunogenicity in SARS-CoV-2 seropositive patients with autoimmune rheumatic diseases prior to and after vaccination.

To investigate the association between physical activity and immunogenicity among SARS-CoV-2 seropositive patients with autoimmune rheumatic diseases prior to and following a 2-dose schedule of CoronaVac (Sinovac inactivated vaccine). This was a prospective cohort study within an open-label, single-arm, phase 4 vaccination trial conducted in Sao Paulo, Brazil. In this substudy, only SARS-CoV-2 seropositive patients were included. Immunogenicity was assessed by seroconversion rates of total anti-SARS-CoV-2 S1/S2 immunoglobulin G (IgG), geometric mean titers of anti-S1/S2 IgG, frequency of positive neutralizing antibodies, and neutralizing activity before and after vaccination. Physical activity was assessed through a questionnaire. Model-based analyses were performed controlling for age (30 kg/m2), and use of prednisone, immunosuppressants, and biologics. A total of 180 seropositive autoimmune rheumatic disease patients were included. There was no association between physical activity and immunogenicity before and after vaccination. This study suggests that the positive association between physical activity and greater antibody responses seen in immunocompromised individuals following vaccination is overridden by previous SARS-CoV-2 infection, and does not extend to natural immunity

Dietary β-alanine intake assessed by food records does not associate with muscle carnosine content in healthy, active, omnivorous men and women.

β-alanine (BA) is one of the most widely used sport supplements, due to its capacity to improve high intensity exercise performance by increasing muscle carnosine (MCarn) content, and consequently, the buffering capacity of the muscle. BA is also available in a variety of animal foods, but little is currently known about the influence of dietary BA intake on MCarn. The aim of the current study was to compile a detailed summary of available data on the BA content of commonly consumed foods, and to explore whether associations could be detected between self-reported dietary BA intake and skeletal MCarn in a group of 60 healthy, active, omnivorous men and women. Dietary BA intake was assessed via 3-day food records and MCarn content assessed by high performance liquid chromatography. A series of univariate and multivariate linear regression models were used to explore associations between estimated dietary BA and MCarn. No evidence of associations between dietary BA intake and MCarn were identified, with effect sizes close to zero calculated from models accounting for key demographic variables (f2 ≤ 0.02 for all analyses). These findings suggest that capacity to increase MCarn via dietary strategies may be limited, and that supplementation may be required to induce increases of the magnitude required to improve performance

Ultra-processed food consumption associates with higher cardiovascular risk in rheumatoid arthritis

To investigate the association between food consumption stratified by processing level and cardiovascular risk factors in rheumatoid arthritis. In this cross-sectional study, 56 patients (age: 62.5 +/- 7.9 years, BMI: 28.4 +/- 5.1 kg/m(2)) had food consumption evaluated according to the processing level (e.g., unprocessed or minimally processed foods, processed foods, and ultra-processed foods) and associated with cardiovascular risk factors. The most prevalent food processing level was unprocessed or minimally processed foods (42.6 +/- 12.6% of total energy intake [TEI]), followed by processed (24.2 +/- 11.9%TEI), ultra-processed (18.1 +/- 11.8%TEI), and culinary ingredients (15.1 +/- 6.4%TEI). Adjusted regression models showed that higher consumption of ultra-processed foods was positively associated with Framingham risk score (beta = 0.06, CI: 95% 0.001, 0.11, p = 0.045) and glycated hemoglobin (beta = 0.04, CI: 95% 0.01, 0.08, p = 0.021). In contrast, higher consumption of unprocessed or minimally processed foods was associated with lower 10-year risk of developing cardiovascular diseases (beta = -0.05, CI: 95% - 0.09, -0.003, p = 0.021) and LDL (beta = -1.09, CI: 95% - 1.94, -0.24, p = 0.013). Patients with rheumatoid arthritis consuming more ultra-processed foods showed worse metabolic profile, whereas those consuming more unprocessed or minimally processed foods had lower cardiovascular risks. A food pattern characterized by a high ultra-processed food consumption appears to emerge as a novel, modifiable risk factor for cardiovascular diseases in rheumatoid arthritisCNPQ - Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPESP – Fundação de Amparo à Pesquisa Do Estado De São Paulo301571/2017-1; 309514/2018-52017/17837-1; 2016/23319-0; 2017/13552-2; 2015/26937-