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PURPOSE: This study evaluated the effect of aspartate (ASP) and asparagine (ASG) supplementation on fatigue determinants in Wistar rats exercised to exhaustion by swimming. METHODS: The animals were tested for anaerobic threshold (AT) determination and then supplemented with 350 mM ASP + 400 mM ASG x day(-1) (AA group, n = 16) or 2 ml x day(-1) of distillated water (PLC group, n = 16) for 7 days. On the 7th day of supplementation, the animals were divided into 4 new groups and killed at rest (RAA, n = 8; RPLC, n = 8), or immediately after the swimming exercise to exhaustion (EAA, n = 8; EPLC, n = 8). R: No significant differences were observed between amino acids and placebo rest groups for muscle and liver glycogen, blood glucose, lactate, alanine, and glutamine concentrations. However, in the exhaustion groups, the EAA group showed higher exercise time (68.37 +/- 25.42 x 41.12 +/- 13.82 min, p <.05) and lower blood lactate concentration (8.57 +/- 1.92 x 11.28 +/- 2.61 mmol x L(-1), p <.05) than the EPLC group. Moreover, the ASP+ASG supplementation decreased the rate of glycogen degradation of gastrocnemius (1.00 +/- 0.51 x 3.43 +/- 0.99 microg x 100 mg of tissue sample(-1) x min(-1), extensor digitorius longus (5.70 +/- 2.35 x 8.11 +/- 3.97 microg. 100 mg of tissue sample(-1) x min(-1) and liver (0.51 +/- 0.34 x 3.37 +/- 2.31 microg x 100 mg of tissue sample(-1) x min(-1) for EAA. Conclusion: These results suggest that ASP+ASG supplementation may increase the contribution of oxidative metabolism in energy production and delay fatigue during exercise performed above the AT. [ABSTRACT FROM AUTHOR]

Women of childbearing age have variations in substrate oxidation rates that can lead to overweight, type II diabetes, and other conditions that may be associated with metabolic inflexibility and the variations in estrogen concentrations observed during the monthly ovarian cycle., Purpose: This study aimed to verify and compare the influence of eight treadmill high-intensity interval training (HIT) sessions on carbohydrate and lipid oxidation rates (CHOox and LIPox, respectively) and intensities of ventilatory anaerobic thresholds (VATs) of women in different phases of the monthly ovarian cycle., Methods: Eleven irregularly active women performed incremental treadmill exercise testing followed by submaximal work-rate running for 45 min to determine VATs, VO 2peak , peak velocity (V peak ), and substrate oxidation rates, before and after a training period, in different phases of their monthly ovarian cycle (follicular phase group, FL, n = 6; luteal phase group, LT, n = 5). The training period consisted of eight HIT sessions, composed each one of eight sets of 60 s running at 100%V peak interspersed by 75 s recovery every 48 h., Results: Our results showed no significant differences in VATs intensities between groups. The comparison between groups showed significant differences in relative energy derived from CHO pre- and post-training of -61.42% and -59.26%, respectively, and LIP pre- and post-training of 27.46% and 34.41%, respectively. The relative energy derived from CHO after the training period was 18.89% and 25.50% higher for FL and LT, respectively; consequently, the relative energy derived from LIPox after the training period was 8,45% and 3.46% lower for FL and LT, respectively. Over the training period, V peak was ~13.5 km/h, which produced the relative intensities of ~89%VO 2peak e ~93%HR peak for both groups., Conclusion: The monthly ovarian cycle phases promote significant changes in substrate oxidation rates leading to a decrease in CHOox. High-intensity interval training can minimize the differences observed and constitute an alternative intervention.

To evaluate the effect of high-intensity interval training (HIT) on the cardiorespiratory performance and substrate oxidation pattern in insulin-resistant and insulin-sensitive obese adolescents., Methods: We recruited 25 obese adolescents in three schools, and trained them in six HIT sessions, comprising of six series at 100% and recovery at 50% peak velocity (Vpeak). For the evaluation, the participants were divided into two groups: insulin-resistant (IR, n = 12; HOMA index ≥3.16) and insulin-sensitive (IS, n = 13). All participants underwent cardiopulmonary and indirect calorimetry testing. We compared the effects of HIT before and after the intervention among the two groups. The data were analyzed using Student's t and Mann-Whitney (intergroup comparisons) and Student's t and Wilcoxon (pre- and post-training comparisons) tests; and Cohen's d (influence of HIT)., Results: There was a significant post-training increase in Vpeak, oxygen consumption (VO2), velocity (V), and heart rate (HR) at the exertion intensity at the first ventilatory anaerobic threshold (VAT1) in both groups ( p < 0.05; d < 0.02). The exercise promoted changes in substrate oxidation rates of the groups, with an increase in carbohydrate oxidation (CHOox) for both IR ( p = 0.064) and IS ( p = 0.034)., Conclusion: Six HIT sessions improved cardiorespiratory performance in both groups and increased CHOox in insulin-sensitive obese adolescents, suggesting its utility for increasing physical fitness and controlling glycemia in these population groups.

Introduction: Neuromuscular electrical stimulation (NMES) is used by athletes to improve muscle performance. However, evidence on the use of NMES in long distance runners is scarce. As such, this study aimed to evaluate the effects of NMES on the muscle torque and sports performance of long-distance recreational runners., Methods: This was a blinded randomized controlled trial. Data from 30 volunteers were analyzed. Participants were randomly allocated to an experimental (n = 15) or control group (n = 15). The experimental group was submitted to running training (RT) and a strengthening protocol with NMES (1 kHz, modulated in 2 ms bursts, 50 Hz modulated burst frequency and 10% duty cycle, 15 min totaling 18 contractions per sessions) for 6 weeks, with 3 sessions per week, while controls were submitted to RT alone. The following variables were analyzed: peak isometric (ISO), concentric (CON), and eccentric (ECC) torque of the quadriceps muscle in voluntary contractions, ventilatory anaerobic thresholds (VATs), maximal oxygen uptake (VO2max), and oxygen cost of transport (OCT)., Results: The NMES group obtained higher values of ISO, 21.04% (p = 0.001), CON, 21.97% (p = 0.001) and ECC, 18.74% (p = 0.001) peak torque and VAT1, 9.56% (p = 0.001), as well as a statistically significant improvement in oxygen cost of transport at VAT1 when compared to controls (p = 0.001)., Conclusion: NMES was effective in improving peak isometric, concentric and eccentric quadriceps muscle torque, in addition to being an interesting resource for enhancing sports performance in long-distance recreational runners and future clinical trials should be performed to compare the use of NMES to different forms of training over longer training periods., Competing Interests: Declaration of competing interest The authors certify that there are no conflicts of interest with any financial organization regarding the material discussed in the manuscript., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Introduction: The characterization of immune and oxidative stress responses to acute and chronic exercise training is important because it may aid in the safety and dose-response prescription of resistance training (RT) in many populations. Purpose: The present study compared changes in acute oxidative stress and markers of apoptosis in immune cells before and after 8 weeks of low-load RT with total or partial blood flow restriction (BFR) versus high-load traditional RT. Methods: Twenty-seven untrained men were randomly divided into three groups: traditional RT [75% one-repetition maximum (1-RM)], RT with partial (20% 1-RM), and total BFR (20% 1-RM). Over an 8-week period, participants performed six sets of arm curls until failure with 90 seconds of recovery for 3 days/week. Blood samples were obtained before and after the first and last training sessions. Results: Data indicated that all training groups showed similar increases in muscular strength ( p < 0.001), reduction in mitochondrial membrane potential (MMP) after exercise in neutrophils ( p < 0.001), and increase in caspase-3 activity after exercise ( p < 0.001). Traditional RT and total BFR showed increased plasma lipid peroxidation ( p < 0.001) and protein carbonyls ( p < 0.001) and lower levels of reduced glutathione (GSH) ( p < 0.001) after exercise. No change was observed in oxidative stress biomarkers in response to partial BFR ( p > 0.05). Conclusion: Data show that RT with partial BFR can increase muscular strength but still does not augment biomarkers of oxidative stress in untrained men. In addition, RT with total BFR promoted similar responses of oxidative stress and markers of immune cell apoptosis versus traditional RT., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 de Lima, Marin, Ferreira, Sousa Filho, Astorino, Prestes, Marquezi and Otton.)

The rating of perceived exertion (RPE) can be used to monitor the exercise intensity during laboratory and specific tests, training sessions, and to estimate the internal training load of the athletes. The aim of the present study was to develop and validate a specific pictorial perceived exertion scale for soccer players (indoor, field, and beach soccer) called GOAL Scale. The pictorial GOAL Scale (six drawings; 1 "low exertion" to 6 "exhaustion") was validated for twenty under-17 soccer players (16.4 ± 0.68 years; 175.4 ± 9 cm; 66.4 ± 7.7 kg; % fat mass 12.4 ± 3.3). In the validation phase, the athletes were evaluated in a progressive protocol involving stimuluses of 3 min with 1 min for the rest into the stages until the voluntary exhaustion in Maximal Cardiopulmonary Effort Test (MCET), and in the Yo Yo Intermittent Recovery Test - Level 1 (Yo-Yo). The RPE identified by the GOL Scale, by the Borg Scale 6 - 20 and by the Cavasini Scale, as well as the heart rate (HR), perceptual of the heart rate (%HR max ) and the blood lactate concentration ([La]) were immediately evaluated after each stage of both tests. Spearman's correlation coefficient ( p < 0.05) was used. Construct scale validity was examined by regressing GOAL Scale against Borg Scale 6 - 20 and Cavasini Scale and concurrent scale validity was investigated by regressing GOAL Scale against HR, beats/min and blood lactate concentration (mmol/L) during two progressive tests. There was a significant correlation values of the GOAL Scale with Borg Scale ( r = 0.93; r = 0.88), Cavasini Scale ( r = 0.91; r = 0.90), %HR max ( r = 0.91; r = 0,86), HR ( r = 0.87; r = 0.83) and lactate ( r = 0.68; r = 0.83) during tests (Maximal Incremental Cardiopulmonary Test and Yo-Yo test, respectively). The results evidenced concurrent and construct validity of the GOAL Scale across a wide range of exercise intensity. The absence of verbal anchors makes the use of this instrument to soccer, futsal and beach soccer athletes of different languages and different literacy levels possible., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Polito, Marquezi, Marin, Villas Boas Junior and Brandão.)

New Findings: What is the topic of this review? A meta-analysis of the efficacy of high intensity interval training (HIIT) in reducing weight, total fat mass (FM) and (intra)-abdominal FM in normal-weight and overweight/obese women before and after menopause. What advances does it highlight? HIIT programmes in women significantly decrease body weight and total and abdominal FM. Their effects are more evident in pre- than in postmenopausal women. Cycling HIIT seems more effective than running, especially in postmenopausal women, and training interventions longer than 8 weeks comprising three sessions a week should be promoted., Abstract: High-intensity interval training (HIIT) is a stimulating modality for reducing body weight and adipose tissue. The purpose of this meta-analysis was to assess the efficacy of HIIT in reducing weight, total fat mass (FM) and (intra)-abdominal FM in normal-weight and overweight/obese women before and after menopause. A structured electronic search was performed to find all publications relevant to our review. Stratified analyses were made of hormonal status (pre- vs. postmenopausal state), weight, HIIT modalities (cycling vs. running), programme duration (< or ≥8 weeks) and the methods used to measure body composition (dual-energy X-ray absorptiometry vs. computed tomography, Magnetic Resonance Imaging and others). A total of 38 studies involving 959 subjects were included. Our meta-analysis showed that overall HIIT programmes significantly decrease weight, total and abdominal FM in women. Both normal weight and overweight/obese women lost total FM after HIIT protocols whereas HIIT was only effective in decreasing abdominal FM in women with excess adiposity. When pre- and postmenopausal women were considered separately, the effect of HIIT on weight, total and abdominal FM were only significant before menopause. Cycling HIIT seemed more effective than running, especially in postmenopausal women, and training interventions longer than 8 weeks comprising three sessions were more efficient. HIIT is a successful strategy to lose weight and FM in normal weight and overweight/obese women. However, further studies are still needed to draw meaningful conclusions about the real effectiveness of HIIT protocols in postmenopausal women., (© 2020 The Authors. Experimental Physiology © 2020 The Physiological Society.)

This study investigated the acquisition of a serial motor skill in individuals with Down syndrome with two levels of handicap, mild group (mean age = 14.5 years, SD = 2.3, 7 individuals) and moderate group (mean age = 15.2 years, SD = 3.2, 7 individuals). The task involved single-arm sequential movements to five. The measures to access performance were overall sequence error, reaction time, and total movement time. To evaluate action program, formation variability of sequencing and relative timing variability were considered. Although there was no clear practice effect, the results showed that the level of handicap led to different strategies to plan and control the actions. The moderate group presented a less stable action program expressed in the variability in sequencing and timing. Their longer reaction times also suggest a heavy demand on central processing in accord with the one-target advantage hypothesis and also due to memory deficits to select and plan movements.

A chemotherapeutic protocol using carmustine in combination with vincristine and prednisone was tested in dogs with multicentric malignant lymphosarcoma. Of seven dogs treated, six (85.7%) achieved complete remission. A partial response occurred in one dog. Median survival time was 224 days (mean 386 days), and median duration of remission was 183 days (mean 323 days). Marked neutropenia was observed following carmustine administration. There were no significant alterations in platelets and red blood cell counts during treatment, and no abnormalities attributable to the chemotherapy were found in serum biochemical profiles. Results of this study showed that carmustine is an effective alternative option in the treatment of canine lymphosarcoma.

The aim of this study was to evaluate the accuracy of serum beta-hydroxybutyrate (beta-OHB) measurements for the diagnosis of diabetic ketoacidosis (DKA) in dogs. One hundred sixteen diabetic dogs were prospectively enrolled in the study: 18 insulin-treated (IT) diabetic dogs that had a positive urine ketone test and 88 untreated, newly diagnosed diabetic dogs. Venous blood gas tensions and pH, serum glucose and urea nitrogen (SUN), and electrolyte (Na+, Cl-, and K+) and urine acetoacetate (AA) concentrations were measured concurrently with serum beta-OHB concentrations. On the basis of laboratory findings, the patients were assigned to I of 3 groups: diabetic ketoacidosis (n = 43); diabetic ketosis (DK, n = 41); and nonketotic diabetes (NDK, n = 31). Serum beta-OHB concentrations differed significantly (P < .001) among the study groups. Although marked differences in beta-OHB concentrations were found, a considerable overlap exists between the distributions of dogs with DK and those with DKA. The overall accuracy of beta-OHB determination as a diagnostic test for DKA, determined by the area under the receiver operating characteristic (ROC) curve, was 0.92. In the 1.9- to 4.8-mmol/L range, serum beta-OHB determination sensitivity varied from 100 to 35.7%, whereas specificity varied from 39 to 100%. The cutoff value of 3.8 mmol/L showed the best equilibrium between specificity (95%), sensitivity (72%), and likelihood ratio (14.8). We concluded that the quantitative measurement of serum beta-OHB may be a potential tool for diagnosing and monitoring ketosis and ketoacidosis in diabetic dogs.