Human metabolism and body composition: prospects for novel studies.

CONTEXT: Most articles on gut microbiota argue the importance of body composition assessment in patients; however, body composition assessments are fragile (ie, with methodological limitations) in the most recent studies. OBJECTIVE: To present two suggestions for further research using the human body composition assessment. METHODS: The methods used in this study are based on a Pinto et al article published in Nutrition Reviews. DATA EXTRACTION: On the basis of data.obtained from the PubMed, SCOPUS, LILACS, and Web of Science databases, Pinto et al provided a current survey of intermittent fasting protocols and an understanding of the outcomes to date in terms of the profile of the intestinal microbiota in obese organisms. DATA ANALYSIS: Of the 82 original articles identified from the databases, 35 were eliminated because of duplication and 32 were excluded for not meeting the inclusion criteria. Two additional articles found in a new search were added, yielding a total of 17 studies to be included in this review. Among the protocols, alternate-day fasting and time-restricted feeding were the most common, and they were shown to have different mechanisms of metabolic signaling. Time-restricted feeding influences body mass control and biochemical parameters by regulating the circadian system and improving satiety control systems by acting on leptin secretion. In contrast, alternate-day fasting leads to a reduction of ±75% of all energy consumption regardless of dietary composition, in addition to promoting hormonal adjustments that promote body mass control. Furthermore, both protocols could remodel the intestinal microbiota by changing the Firmicutes to Bacteroidetes ratio and increasing the abundance of strains such as Lactobacillus spp. and Akkermansia that have a protective effect on metabolism against the effects of body mass gain. CONCLUSION: Changes in adipose tissue (eg, body mass loss, control, gain) should be interpreted via the sum of skinfolds in absolute values, waist perimeter, and patients' body proportionality, because fat is just a fraction of the adipocyte (lipid).

Eccentric, but not concentric muscle contraction induce inflammation and impairs fibrinolysis in healthy young men.

Different types of muscle contraction can cause different damage to the musculature and differences in inflammatory responses. Acute increases in circulatory inflammation markers can influence the crosstalk between coagulation and fibrinolysis processes, increasing the risk of thrombus formation and detrimental cardiovascular events. The aim of this study was to analyze the effects of concentric and eccentric exercise on hemostasis markers, C-reactive protein (CRP), and the relationship between these variables. Eleven healthy subjects with a mean age of 25.4 ± 2.8, non-smokers, with no history of cardiovascular disease and blood type O, randomly performed an isokinetic exercise protocol consisting of 75 concentric (CP) or eccentric (EP) contractions of knee extension, divided into five sets of 15 repetitions combined with 30-s rest. Blood samples for analysis of FVIII, von Willebrand factor, tissue plasminogen activator (t-PA), plasminogen activator inhibitor type-1 (PAI-1), and CRP were collected pre, post, 24 h, and 48 h after each protocol. Increased levels of CRP at 48 h in EP versus CP (p = 0.002), increased PAI-1 activity 48 h in EP versus CP (p = 0.044), and a reduction in t-PA at 48 h when compared with post-protocol in both protocols (p = 0.001). A correlation was found between CRP and PAI-1 at 48 h of PE (r2 = 0.69; p = 0.02). This study showed that both EP and CP increase the clotting process, albeit only the exercise performed eccentrically induces inhibition of fibrinolysis. This is possibly due to the increase in PAI-1 48 h after the protocol, which correlates with the increase in inflammation as demonstrated by the CRP levels.

Fasted exercise does not improve postprandial lipemia responses to different meals in lean and obese subjects: A crossover, randomized clinical trial.

INTRODUCTION: Persistent episodes of postprandial hyperlipemia (PPL) and hyperglycemia (PPG) are considered risk factors for coronary heart disease (CHD) and premature death; whereas physical exercise improves lipid profile and glucose tolerance thus decreasing cardiovascular risks. OBJECTIVE: To investigate the effects of low-intensity fasted aerobic exercise on the magnitude of the PPL and PPG responses to meals with different energy content, in normal and obese subjects. METHODS: The study used a randomized crossover design. Twenty-one male (Lean: n = 9, BMI: 24.3 ± 2.2; and obese: n = 12, BMI 32.31 ± 2.1) volunteers aged 20-30 years, performed three interventions, separated by 7 days each: (i) 45 min at rest and isocaloric high-fat meal (60% lipids, 30% carbohydrates and 10% protein); (ii) fasted low-intensity aerobic exercise (50% VO2max) for 45 min followed by an isocaloric or (iii) calorie deficit high-fat meal. Subjects were serially assessed for blood triglycerides, and glucose levels. RESULTS AND CONCLUSIONS: Low-intensity fasted aerobic exercise had no acute effect on PPL in lean and obese subjects. Glucose concentrations were reduced only in lean subjects. There is a significant difference in PPL values when comparing lean to obese subjects, implying that the nutritional status influences lipid and carbohydrate after fasted low-intensity aerobic exercise. Registered under ClinicalTrials.gov Identifier no. NCT00929890.

Occurrence and patterns of orofacial injury in CrossFit practitioners.

BACKGROUND: CrossFit is an activity that can provide positive influences on body composition and physical fitness. However, the occurrence or pattern of possible injuries, especially in the orofacial region, has not yet been studied. The aim of this study was to investigate the occurrence and patterns of orofacial injuries in CrossFit practitioners. MATERIAL AND METHODS: This was a cross-sectional study carried out using an online questionnaire on the Google Forms platform. The volunteers were self-selected men and women who practice CrossFit and reside in Brazilian municipalities. The online survey was conducted during April 2020 and comprised 12 questions. The data were analyzed, categorized, and presented as percentages. RESULTS: These were 65 (27.8%) participants who reported having suffered at least one episode of orofacial trauma and they were more prevalent during training sessions 58 (89.2%). Among the regions with the highest frequency of injuries, the head 23 (21%), mental protuberance 22 (19.6%), upper lip 19 (16.9%), and maxillary teeth 14 (12.5%) were the most cited. CONCLUSIONS: The prevalence of injuries in the head region indicates a potential concern. Preference should be given to making mouthguards for the maxillary teeth, as they are significantly more affected by trauma during CrossFit when compared to the mandibular teeth.

Correction to: Periodontal Disease Impairs Muscle Recovery by Modulating the Recruitment of Leukocytes.

The original version of this article contained mistakes, and the authors would like to correct them.

Periodontal Disease Impairs Muscle Recovery by Modulating the Recruitment of Leukocytes.

The purpose of this study is to analyze the impact of periodontal disease (PD) associated with physical exercise on inflammatory mediators and muscle repair. Twenty-four Wistar rats were divided into four groups: control (SH), healthy trained (TH), sedentary with PD (SP), and trained with PD (TP). PD was induced in groups SP and TP while the trained groups performed treadmill exercises for 8 weeks. For the analysis of IL-6, IL-10, TNF-α, and leukocyte count, we collected blood samples. Cryolesions were induced in the tibialis anterior and gastrocnemius, which were analyzed for morphological changes. The presence of PD modified leukocyte counts, while exercise showed an additive role. PD increased levels of IL-6, IL-10, and TNF-α, and physical exercise changed only values of IL-10. The association between physical exercise and PD was responsible for an increased concentration of leukocytes in the region of the inflammation. Serum levels of inflammatory markers were modified by PD and, when combined with exercise, may negatively modulate inflammation. The association between PD and physical exercise showed the most significant changes in the number of inflammatory cells and may negatively influence the process of muscle repair.

Combined and Isolated Effects of Alcohol Intake and One Night of Sleep Deprivation on Mood States, Hormonal and Inflammatory Responses in Healthy Male Adults: a Crossover Randomized Controlled Trial.

Alcohol (ALC) intake and sleep deprivation (SDP) are conditions that cause changes in the physiological status. However, the relationship between biological markers and mood states is not entirely clear yet. The purpose of the study was to compare isolated and combined effects of ALC intake and SDP on hormonal and inflammatory responses and in changes in the state of mood. Also, we intended to explain possible changes in mood states through biochemical variations using multiple stepwise regression analysis. Ten healthy male were randomized in four situations: (1) placebo intake + normal sleep (PLA + SLE); (2) ALC intake + SLE; (3) PLA intake + SDP; (4) ALC intake + SDP. While subjects ingested ALC (1 g/kg of beer), PLA intake was a non-alcoholic beer. The subjects had one night of SLE or were subjected to SDP in the lab for 8 h. After each experimental condition, morning blood samples were taken for assessments of serum levels of glucose, cortisol, testosterone, epinephrine, interleukin-6 (IL-6), interleukin-10 (IL-10) and C-reactive protein (CRP). The subjects were also asked to fill in a Profile of Mood State questionnaire. The results showed that the glucose level was significant lower in ALC + SDP compared to the PLA + SLE condition. Total Mood Disturbance was lower in ALC + SDP and PLA + SDP compared to the PLA + SLE condition. Fatigue was higher under SDP conditions compared to PLA + SLE. Vigor was lower under the ALC + SDP condition compared to the PLA + SLE condition. Regression analysis showed that Total Mood Disturbance and fatigue under ALC + SDP were associated with changes in the cortisol levels. Our results showed that combined and isolated ALC intake and one night of SDP did not change the hormonal and inflammatory responses tested, and the combined effects caused a reduction in the glucose levels. Vigor, fatigue and Total Mood Disturbance were affected by each condition. Furthermore, Total Mood Disturbance and fatigue were possibly explained by changes in the cortisol levels in the combined condition.

Maturity Status Does Not Exert Effects on Aerobic Fitness in Soccer Players After Appropriate Normalization for Body Size.

The present study investigated the effects of pubertal status on peak oxygen uptake (VO2peak), respiratory compensation point (RCP), and ventilatory threshold (VT) in young soccer players using different body size descriptors. Seventy-nine soccer players (14 prepubescent, 38 pubescent and 27 postpubescent) participated in this study. A maximal exercise test was performed to determine the VO2peak, RCP, and VT. Ultrasonography was used to measure lower limb muscle volume (LLMV). LLMV (mL-b) was rated as the most effective body size descriptor to normalize VO2peak (mLO2·mL-0.43·min-1), RCP (mLO2·mL-0.48·min-1), and VT (mLO2·mL- 0.40·min-1). The values of VO2peak, RCP, and VT relative to allometric exponents derived by LLMV were similar among groups (p > .05; 0.025 < η2 < 0.059) when the effect of chronological age was controlled. Allometric VO2peak, RCP, and VT values were: 100.1 ± 7.9, 107.5 ± 9.6, and 108.0 ± 10.3 mLO2.mL-0.43·min-1; 51.8 ± 5.3, 54.8 ± 4.7, and 57.3 ± 5.8 mLO2·mL-0.48·min-1; and 75.7 ± 7.1, 79.4 ± 7.0, and 80.9 ± 8.3 mLO2·mL- 0.40·min-1 for prepubertal, pubertal, and postpubertal groups, respectively. Maturity status showed no positive effect on VO2peak, RCP, and VT when the data were properly normalized by LLMV in young soccer players. Allometric normalization using muscle volume as a body size descriptor should be used to compare aerobic fitness between soccer players heterogeneous in chronological age, maturity status, and body size.

Supersets do not change energy expenditure during strength training sessions in physically active individuals.

BACKGROUND/OBJECTIVE: The energy expenditure (EE) in strength training (ST) is analyzed both during and after each training session. However, little information exists about the influence of strength exercises supersets on EE. We aimed to determine whether supersets of ST exercises influenced EE during and after one strength exercise session. METHODS: Twenty men were randomly divided to perform either a session with grouped exercises for the same muscle (GE: 26.6 ± 3.4 years; 17.4 ± 3.4 body fat) or a session with separated exercises (SE: 24.9 ± 2.6 years; 15.4 ± 5.9 body fat). Four exercises (5 sets of 8-10 maximum repetitions) for knee extensor muscles and shoulder horizontal flexor muscles were executed in both training sessions. The EE of each experimental session was obtained through the analysis of oxygen uptake during and after exercise (60 minutes postsession). RESULTS: Total work during the session and increases in lactate concentrations were similar between the GE and SE Groups. During exercise, EE was greater in the SE Group when compared with the GE Group (GE: 123.8 ± 14.36 kcal vs. SE: 131.77 ± 20.91 kcal). During the postexercise period, GE induced greater EE when compared with SE (GE: 25.12 ± 7.86 kcal vs. SE: 19.76 ± 5.53 kcal). However, the exercise sequence did not influence overall EE (GE: 148.92 ± 18.72 kcal vs. SE: 151.53 ± 17.97 kcal, p = 0.920). CONCLUSION: Our findings indicate that, in physically active men, ST supersets do not influence total EE during and 60 minutes after a single session.

Validation of predictive equations for basal metabolic rate in eutrophic and obese subjects / Validação de equações de predição da taxa metabólica basal em sujeitos eutróficos e obesos

Prediction equations for basal metabolic rate (BMR) continue to be the most common clinical tool for diet prescription; however, the values estimated may differ from those measured by indirect calorimetry (IC), especially in obese subjects. The objective of this study was to determine the BMR of obese and eutrophic subjects by IC, and to compare the results obtained with those estimated by prediction equations in order to identify whether differences exist between predicted values and those measured by IC. Forty men aged 18 to 30 years were evaluated; of these, 20 were grade 1 obese and 20 were eutrophic. The agreement between the prediction equations and IC was evaluated using Bland-Altman (1986) plots. The results showed a variation between the prediction equations and IC of -19.6% to -91% in obese subjects and of 4.2% to 4.4% in eutrophic subjects. In both groups, the Mifflin-St. Jeor equation (1990) was the most accurate, with a difference of -9.1% compared to IC in obese subjects and of 0.9% in eutrophic subjects. This study indicates the Mifflin-St. Jeor equation to be the most adequate to estimate BMR. However, it is important to measure the BMR of obese subjects more accurately and safely in order to establish the best intervention based on physical exercise and healthy eating.

Equações de predição para taxa metabólica basal (TMB) são amplamente utilizadas para prescrição dietética, porém podem apresentar valores diferentes daqueles medidos por calorimetria indireta (CI), principalmente, em indivíduos obesos. O objetivo deste estudo foi verificar os valores de TMB por meio da CI em indivíduos obesos de grau I e eutróficos e comparar com os resultados obtidos pelas equações de predição, a fim de identificar se existe discrepância nos valores obtidos entre o medido pela CI e o estimado pelas equações. O estudo avaliou 40 homens entre 18 e 30 anos, sendo 20 eutróficos e 20 obesos grau I. Foi verificado o grau de concordância entre as equações e CI por meio da metodologia sugerida por Bland e Altman (1986). Os resultados mostram a variação entre os métodos de predição de -19,6% a -9,1%, quando comparadas a CI nos sujeitos obesos, e de -4,2% a 4,4% nos eutróficos. Em ambos os grupos, a equação que mais se aproxima da estimativa real é a de Miflin St. Jeor (1990), com -9,1% de diferença da CI nos sujeitos obesos e 0,9% nos eutróficos. Desta forma, o presente estudo indica a utilização da equação de Mifflin St. Jeor (1990) para estimar a TMB. Entretanto, é fundamental que se consiga medir a TMB de sujeitos obesos de maneira mais precisa e segura, para melhor conduzir a intervenção baseada em exercícios físicos e boa alimentação.