Net Heart Rate for Estimating Oxygen Consumption in Active Adults.

The aim of this study was to verify the accuracy of predicting oxygen consumption (O2) in predominantly aerobic activities based on net heart rate (netHR), sex, and body mass index (BMI) in active adults. NetHR is the value of the difference between the resting HR (HRrest) and the average HR value obtained during a given session or period of physical activity. These activities must be continuous, submaximal, and of a stabilized intensity. The magnitude of the netHR depends mainly on the intensity of the exercise. The HR is measured in beats per minute (bpm). A total of 156 participants, 52 women and 104 men, between the ages of 18 and 81, had their netHR and net oxygen intake (netVO2) assessed. There were 79 participants in group 1 (prediction sample) (52 males and 27 females). There were 77 people in group 2 (validation sample) (52 males and 25 females). The results of the multiple linear regression showed that netVO2 (R2 = 85.2%, SEE = 3.38) could be significantly predicted by sex (p < 0.001), netHR (p < 0.001), and BMI (p < 0.001). The Bland-Altman plots satisfied the agreement requirements, and the comparison of the measured and estimated netVO2 revealed non-significant differences with a trivial effect size. We calculated the formula NetVO2 (mL/(kg·min)) = 16 + 3.67 (sex) + 0.27 (netHR) - 0.57 (BMI) to predict netVO2, where netVO2 is the amount of oxygen uptake (mL/(kg·min)) above the resting value, netHR is the heart rate (beats per minute) above the resting value measured during exercise, sex is equal to zero for women and one for men, and BMI is the body mass index. In addition, based on the knowledge of VO2, it was possible to estimate the energy expenditure from a particular training session, and to determine or prescribe the exercise intensity in MET (metabolic equivalent of task).

Effects of a 16-Week Training Program with a Pyramidal Intensity Distribution on Recreational Male Cyclists.

Different training intensity distributions (TIDs) have been proposed to improve cycling performance, especially for high-competition athletes. The objectives of this study were to analyze the effect of a 16-week pyramidal training intensity distribution on somatic and power variables in recreational cyclists and to explore the training zone with the greatest impact on performance improvement. The sample consisted of 14 male recreational cyclists aged 41.00 ± 7.29 years of age. A number of somatic variables were measured. During an incremental protocol, power at a 4 mMol·L-1 blood lactate concentration (P4), corresponding power to body mass ratio (P/W P4), and heart rate (HR P4) were also measured. Among the somatic variables, the percentage of fat mass showed the greatest improvement between moments (p < 0.001, d = 0.52). Both P4 (p < 0.001, d = 1.21) and P/W P4 (p < 0.001, d = 1.54) presented a significant increase between moments. The relative improvement in P4 (% P4) showed a significant correlation (Rs = 0.661, p = 0.038) and relationship (R2 = 0.61, p = 0.008) mainly with training zone Z2 (blood lactate levels ≥ 2 and <4 mMol·L-1). It seems that spending more time in Z2 promoted an improvement in both somatic and power variables in recreational cyclists.

Prevalence of Type 2 Diabetes, Impaired Fasting Glucose, and Diabetes Risk in an Adult and Older North-Eastern Portuguese Population.

The aims of this study were (1) to evaluate the prevalence of type 2 diabetes (T2D) in a middle-aged north-eastern Portuguese population, (2) to analyze the prevalence of impaired fasting glucose (IFG), and (3) to assess the risk of T2D in this community-based sample. An exploratory, retrospective, and cross-sectional study was conducted from a total of 6570 individuals aged 18-102 years, among which 3865 were women (57.4 ± 18.1 years) and 2705 were men (60.0 ± 16.8 years). T2D diagnosis, IFG, and the diabetes risk score (low to very high risk) were assessed. The prevalence of T2D in this adult and an older north-eastern Portuguese population was 17.4%. A higher prevalence of T2D was reported in men (22.2%) than in women (14.0%); however, this was without significant differences (p = 0.086). Otherwise, the prevalence of T2D was significantly different among the age groups and increased with age (p < 0.001). Regarding IFG, a higher percentage of cases was observed in men (14.1%) than in women (8.4%) (p < 0.001). The risk of developing T2D in the next 10 years showed an association with sex and age group (p < 0.001) with a small-to-moderate effect (V = 0.1-0.3). Men and the elderly had the highest percentage of cases in the moderate-to-very high-risk bands. The current research confirmed a higher prevalence of T2D, IFG, and diabetes risk than previous Portuguese epidemiological reports. The results also suggest potential prediabetes cases, which should be carefully monitored. The current research adds evidence to the worldwide trend of the increasing prevalence of T2D and intermediate hyperglycemia (i.e., prediabetes).

Validation of StepTest4all for Assessing Cardiovascular Capacity in Young Adults.

BACKGROUND: Cardiovascular capacity, expressed as maximal oxygen uptake (VO2max), is a strong predictor of health and fitness and is considered a key measure of physiological function in the healthy adult population. The purpose of this study was to validate a specific step test (StepTest4all) as an adequate procedure to estimate cardiovascular capacity in young adults. METHODS: The sample was composed of 56 participants, including 19 women (aged 21.05 ± 2.39 years, body mass = 57.50 ± 6.64 kg, height = 1.62 ± 0.05 m, body mass index = 22.00 ± 2.92 kg/m2) and 37 men (aged 22.05 ± 3.14 years, body mass = 72.50 ± 7.73 kg, height = 1.76 ± 0.07 m, body mass index = 23.34 ± 2.17 kg/m2). Participants were included in one of the following groups: (i) the group used to predict the VO2max, and (ii) the group used to validate the prediction model. All participants performed the StepTest4all protocol. The step height and the intensity of the effort was determined individually. Heart rate and oxygen uptake were measured continuously during rest, effort, and recovery phases. The validation process included the following three stages: (i) mean data comparison, (ii) simple linear regression, and (iii) Bland-Altman analysis. RESULTS: The linear regression retained, as significant predictors of the VO2max, sex (p < 0.001) and heart rate recovery for one minute (p = 0.003). The prediction equation revealed a high relationship between measurements (R2 = 63.0%, SEE = 5.58). The validation procedure revealed non-significant differences (p > 0.05) between the measured and estimated maximal oxygen uptake, high relationship (R2 = 63.3%), and high agreement with Bland-Altman plots. Thus, VO2max can be estimated with the formula: VO2max = 22 + 0.3 · (HRR1min) + 12 · (sex), where HRR1min is the magnitude of the HR decrease (bpm) in one minute immediately after the step was stopped, and sex: men = 1, women = 0. CONCLUSIONS: The StepTest4all is an adequate procedure to estimate cardiovascular capacity, expressed as VO2max, in young adults. In addition, it is possible to determine the qualitative level of cardiovascular capacity from the heart rate recovery for one minute, more specifically, poor: <20, moderate: 20 to 34, good: 35 to 49, and excellent: ≥50. This procedure has the benefit of being simple to apply and can be used by everyone, even at home, without specialist supervision.

Structural Equation Modelling for Predicting the Relative Contribution of Each Component in the Metabolic Syndrome Status Change.

Understanding the factor weighting in the development of metabolic syndrome (MetS) may help to predict the progression for cardiovascular and metabolic diseases. Thus, the aim of this study was to develop a confirmatory model to describe and explain the direct and indirect effect of each component in MetS status change. A total of 3581 individuals diagnosed with MetS, aged 18−102 years, were selected between January 2019 and December 2020 from a community-representative sample of Portuguese adults in a north-eastern Portuguese region to test the model's goodness of fit. A structural equation modelling (SEM) approach and a two-way ANOVA (age × body composition) were performed to compare the relative contribution of each MetS component using joint interim statement (JIS). Waist circumference (ß = 0.189−0.373, p < 0.001), fasting glucose (ß = 0.168−0.199, p < 0.001) and systolic blood pressure (ß = 0.140−0.162, p < 0.001) had the highest direct effect on the change in MetS status in the overall population and concerning both sexes. Moreover, diastolic blood pressure (DBP), triglycerides (TG) and high-density lipoprotein cholesterol (HDL-c) had a low or non-significant effect. Additionally, an indirect effect was reported for age and body composition involving the change in MetS status. The findings may suggest that other components with higher specificity and sensitivity should be considered to empirically validate the harmonised definition of MetS. Current research provides the first multivariate model for predicting the relative contribution of each component in the MetS status change, specifically in Portuguese adults.

Prediction of body fat in adolescents: validity of the methods relative fat mass, body adiposity index and body fat index.

OBJECTIVE: To verify the validity of anthropometric methods body adiposity index (BAI), relative fat mass (RFM) and body fat index (BFI) to estimate body fat percentage (%BF) in adolescents. METHODS: A cross-sectional study was carried out with 420 Brazilian adolescents aged 15-19 years, stratified by age (< 18 years, n = 356; ≥ 18 years, n = 64) and sex (boys, n = 216; girls, n = 204). The Anthropometric measurements height, body weight, hip circumference and waist circumference were collected to calculate the %BF by BAI, RFM, BFI methods. Subsequently, %BF was measured by dual emission X-ray absorptiometry (DXA), adopted as a reference method. In the statistical analysis of the data, the Pearson correlation test and the paired t test between %BF obtained by the equations and by the DXA were performed. The method validation criterion was that 68% of individuals should be within an acceptable error range of ± 3.5% of BF and Cohen's Kappa index ≥ 0.61. Additionally, the Bland-Altman graphical analysis was performed. RESULTS: All methods showed a high correlation with DXA. For the Kappa index, only the RFM reached the criterion in the total sample (0.67) and in the sample < 18 years (0.68). None of the methods reached the criterion of 68% of the sample within the error range of ± 3.5% of BF. CONCLUSION: The BAI, RFM and BFI equations were not valid for predicting BF in the studied sample according to the criteria adopted regardless of sex or age. LEVEL OF EVIDENCE: Level V, cross-sectional descriptive study.

Lack of impact of dietary inclusion of dried Artemisia annua leaves for cattle on infestation by Rhipicephalus (Boophilus) microplus ticks.

The present study evaluated whether a natural dietary additive, dried Artemisia annua leaves, may be useful to control Rhipicephalus (Boophilus) microplus on naturally infested cattle. Twenty heifers of the Canchim breed, weighing around 250 kg, were divided into two equally sized experimental groups: 1) control animals and 2) animals receiving 200 g/day of dried A. annua leaves for two months. Before treatment began, the animals were homogeneously distributed in control and treatment groups based on their pre-treatment weight and tick infestation level. Counts of engorged female ticks then occurred weekly during the two-month experimental period. We also monitored cattle weight gain and packed cell volume (PCV). Artemisinin (0.96%) was quantified in the plant material by high-performance liquid chromatography with refractive index detector (HPLC-IR). No statistical differences between the control and treatment groups were observed for engorged female counts (log averages of 1.3 ticks and 1.4 ticks per animal, respectively), daily cattle weight gain (0.910 kg and 0.888 kg, respectively) or PCV (33.5% and 33.0%, respectively). We conclude that the oral supplementation of cattle feed with dried A. annuna leaves did not control natural infestation of R. (B.) microplus. The hypothesis of artemisinin's action on cattle ticks by ingestion through the animals' blood was not confirmed at the evaluated dose.

Anthelmintic activity of Artemisia annua L. extracts in vitro and the effect of an aqueous extract and artemisinin in sheep naturally infected with gastrointestinal nematodes.

There is no effective natural alternative control for gastrointestinal nematodes (GIN) of small ruminants, with Haemonchus contortus being the most economically important GIN. Despite frequent reports of multidrug-resistant GIN, there is no new commercial anthelmintic to substitute failing ones. Although trematocidal activity of artemisinin analogs has been reported in sheep, neither artemisinin nor its plant source (Artemisia annua) has been evaluated for anthelmintic activity in ruminants. This study evaluated the anthelmintic activity of A. annua crude extracts in vitro and compared the most effective extract with artemisinin in sheep naturally infected with H. contortus. A. annua leaves extracted with water, aqueous 0.1% sodium bicarbonate, dichloromethane, and ethanol were evaluated in vitro by the egg hatch test (EHT) and with the bicarbonate extract only for the larval development test (LDT) using H. contortus. The A. annua water, sodium bicarbonate (SBE), ethanol, and dichloromethane extracts tested in vitro contained 0.3, 0.6, 4.4, and 9.8% of artemisinin, respectively. The sodium bicarbonate extract resulted in the lowest LC99 in the EHT (1.27 µg/mL) and in a LC99 of 23.8 µg/mL in the LDT. Following in vitro results, the SBE (2 g/kg body weight (BW)) and artemisinin (100 mg/kg BW) were evaluated as a single oral dose in naturally infected Santa Inês sheep. Speciation from stool cultures established that 84-91% of GIN were H. contortus, 8.4-15.6 % were Trichostrongylus sp., and 0.3-0.7% were Oesophagostomum sp. Packed-cell volume and eggs per gram (EPG) of feces were used to test treatment efficacy. The SBE tested in vivo contained no artemisinin, but had a high antioxidant capacity of 2,295 µmol of Trolox equivalents/g. Sheep dosed with artemisinin had maximum feces concentrations 24 h after treatment (126.5 µg/g artemisinin), which sharply decreased at 36 h. By day 15, only levamisole-treated sheep had a significant decrease of 97% in EPG. Artemisinin-treated and SBE-treated sheep had nonsignificant EPG reductions of 28 and 19%, respectively, while sheep in infected/untreated group had an average EPG increase of 95%. Sheep treated with artemisinin and A. annua SBE maintained blood hematocrits throughout the experiment, while untreated/infected controls had a significant reduction in hematocrit. This is the first time oral dose of artemisinin and an aqueous extract of A. annua are evaluated as anthelmintic in sheep. Although oral dose of artemisinin and SBE, at single doses, were ineffective natural anthelmintics, artemisinin analogs with better bioavailability than artemisinin should be tested in vivo, through different routes and in multiple doses. The maintenance of hematocrit provided by artemisinin and A. annua extract and the high antioxidant capacity of the latter suggest that they could be combined with commercial anthelmintics to improve the well-being of infected animals and to evaluate potential synergism.

The effects of combining Artemisia annua and Curcuma longa ethanolic extracts in broilers challenged with infective oocysts of Eimeria acervulina and E. maxima.

Due to an increasing demand for natural products to control coccidiosis in broilers, we investigated the effects of supplementing a combination of ethanolic extracts of Artemisia annua and Curcuma longa in drinking water. Three different dosages of this herbal mixture were compared with a negative control (uninfected), a positive control (infected and untreated), chemical coccidiostats (nicarbazin+narazin and, later, salinomycin), vaccination, and a product based on oregano. Differences in performance (weight gain, feed intake, and feed conversion rate), mortality, gross intestinal lesions and oocyst excretion were investigated. Broilers given chemical coccidiostats performed better than all other groups. Broilers given the two highest dosages of the herbal mixture had intermediate lesion scores caused by Eimeria acervulina, which was higher than in broilers given coccidiostats, but less than in broilers given vaccination, oregano and in negative controls. There was a trend for lower mortality (P = 0·08) in the later stage of the growing period (23-43 days) in broilers given the highest dosage of herbal mixture compared with broilers given chemical coccidiostats. In conclusion, the delivery strategy of the herbal extracts is easy to implement at farm level, but further studies on dose levels and modes of action are needed.

Chemical and technological evaluation of the Phyllanthus niruri aerial parts as a function of cultivation and harvesting conditions

Tea from Phyllanthus niruri L., Phyllanthaceae, aerial parts is commonly used by Brazilian folk medicine for its benefits on the treatment of genitourinary disorders, for what the polyphenolic compounds are mainly responsible. The yield of such compounds may be influenced by several variables related with the plant growth. The effects of planting periods and harvesting conditions are investigated in this work, including four different seasons. The cultivation was characterized by dry mass yield of aerial parts, and the effect of pruning was analyzed. Leaves, stems and their mixtures were analyzed after drying and milling. Loss on drying and water soluble extractives were used as physical parameters for quality control. Flavonoid content and gallic acid were chosen as chemical markers for this work. The spectrophotometric trial based on the aluminum chloride complexes was applied to evaluate the total flavonoids content. Gallic acid contents were measured from the water extractive solutions by high-performance liquid chromatography. The pruning caused a positive influence on the amount of leaves and stems. The highest flavonoids and gallic acid contents were found in the leaves, which were developed over the summer and the winter, respectively, both from the second harvesting (after pruning). Chomatographic profile by HPLC was characterizes by the presence of gallic acid and two other major peaks (not identified substances), which relation was peculiar to each aerial part. In conclusion, these results suggest that even under less favorable climatic conditions, in winter, the pruning seems to cause a strong influence over the P. niruri polyphenolics production. Indeed, the total flavonoids content, as well as the HPLC profile, can be used as indicative parameters of the ratio of leaves and stem in the vegetal raw material.

New hybrid lines of the antimalarial species Artemisia annua L. guarantee its growth in Brazil

Malaria is still one of the greatest causes of mortality in the world; in Brazil there are over 500,000 reported cases each year. Malaria, caused by the protozoan Plasmodium, has been aggravated by the increasing resistance of Plasmodium to the traditional drugs chloroquine and mefloquine. The study of new drugs resulted in the identification of antimalarial activities of an endoperoxide sesquiterpene lactone, called qinghaosu or atemisinin, extracted from the leaves of Artemisinin annua L., of the Asteraceae family. The research work developed at MEDIPLANT (Switzerland) and CPQBA-UNICAPM (Brazil) involved the selection and breeding of genotypes rich in artemisinin and presenting high biomass followed by a second selection for adaptation to Brazilian climatic conditions. Through controlled hybridization between selected genotypes from China and Vietnam, genetic gain was obtained in terms of artemisinin content and population uniformity. Through the increase of biomass and artemisinin content (estimated by analytical monitoring), it was possible to increase the artemisinin production of 5 Kg/ha for the base population to approximately 25 Kg/ha for the genetically bred population. In the cultivation carried out in Brazil, 3 of 7 hybrid lines, 2/39 x 1V, Ch x Viet.55 and 1V x 2/43 produced respectively 25.43, 23.05 and 21.27 Kg of artemisinin/ha/cut, with 2 harvests possible per year. The cultivation of these new hybrid lines in Brazil is technically feasible and highly competitive, due to the production obtained.