Effects of Dancing Associated With Resistance Training on Functional Parameters and Quality of Life of Aging Women: A Randomized Controlled Trial.

The purpose of the present study was to evaluate the effects of a dance intervention associated with resistance training or health education program on functional paramaters and quality of life of aging women. Thirty-six women were allocated to dance plus resistance training group (D + RT) or dance plus health education group (D + HE). Both interventions lasted 8 weeks and were performed twice a week. Dance sessions lasted 60 min. Resistance training was composed by two to three sets of 10-15 repetitions in five exercises. Improvements were found in 30-s chair stand (D + RT: 6 ± 1 repetitions; D + HE: 7 ± 1 repetitions), 30-s arm curl (D + RT: 7 ± 1 repetitions; D + HE: 7 ± 1 repetitions), 6-min walk (D + RT: 43 ± 12 m; D + HE: 55 ± 12 m), timed up and go (D + RT: -1.1 ± 0.3 s; D + HE: -1.4 ± 0.2 s), and psychological domain of quality of life (D + RT: 6 ± 2%; D + HE: 5 ± 3%), with no difference between groups. Both groups improve functional parameters and quality of life of aging women.

Extra and intra cellular HSP70 levels in adults with and without metabolic disorders: a systematic review and meta-analysis.

Metabolic disorders, such as obesity, type 2 diabetes mellitus (T2DM), and metabolic syndrome (MS) are related to chronic pro-inflammatory conditions. Evidence suggests that heat shock proteins are linked to metabolic disorders. Intracellular HSP70 (iHSP70) is mandatory for normal insulin signalling, and proteostasis, and exerts a powerful anti-inflammatory role. On the other hand, the extracellular (eHSP72) is linked with a pro-inflammatory state and induces insulin resistance in humans. Then, we conducted a systematic review with meta-analysis to summarize the data of HSP70 in people with and without metabolic disorders. PubMed, Embase, Scopus, and Web of Science databases were used. Eligibility criteria included observational and baseline data of experimental studies that assessed iHSP70 and/or eHSP72 in adults with metabolic disorders and healthy people. The risk of bias was assessed by the Newcastle-Ottawa scale. Meta-analysis was performed using a random-effect model and the mean difference was estimated for eHSP72 and the standardized mean difference for iHSP70. A total of 11,255 articles were retrieved, 31 articles were assessed for eligibility and 15 were included for data extraction. There was no difference in eHSP72 between metabolic disorders and healthy controls (mean difference (MD) = 0.11; 95% confidence interval (CIs) = -0.05 to 0.27; I2 = 95%). Subgroup analysis showed higher levels of eHSP72 in T2DM people than healthy ones (MD = 0.32; 95% CIs = 0.17 to 0.47; I2 = 92%). For iHSP70 no difference was found (standardized mean difference (SMD) =-0.24; 95% CIs =-1.62 to 1.15; I2 = 86%). Our results suggest that eHSP72 levels may be dependent on metabolic condition and no difference in iHSP70 levels are attributed to high heterogeneity level between studies (PROSPERO REGISTRATION: CRD42022323514).

Effects of dancing on physical activity levels of children and adolescents: a systematic review.

BACKGROUND: Dancing has been suggested to increase the levels of physical activity of the youth. However, it is not clear what are the physiological characteristics of the dance classes for young people, mainly regarding the levels of moderate to vigorous physical activity (MVPA) during classes. It is also unclear if regular engagement in dance practices can contribute with increases in the amounts of daily/weekly MVPA, recommended by health organizations. OBJECTIVES: To conduct a systematic review verifying the amount of time spent at MVPA (primary outcome), by children and adolescents in the following situations: i) During dance classes, and ii) Before and after dance interventions. Secondary outcomes included: markers of exercise intensity during class, such as oxygen consumption (VO2) and heart rate (HR); VO2peak and lipid profile before and after dance interventions. METHODS: Six data sources were accessed (MEDLINE, EMBASE, Cochrane Wiley, PEDRO and SCOPUS). Study selection included different designs (acute, cohort, randomized controlled trials and others). Participants were from 6 to 19 years old, regularly engaged in dance practices. Methodological quality was assessed using the Downs and Black checklist. Two independent reviewers extracted characteristics and results of each study. RESULTS: 3216 articles were retrieved, and 37 included. Studies indicated that dance classes do not achieve 50% of total class time at MVPA. However, there are peaks of HR and VO2 during dance classes, which reach moderate and vigorous intensities. MVPA/daily/weekly did not improve before and after dance interventions for most of the studies, also VO2peak did not. The few results on lipid profile showed improvements only in overweight and obese participants. LIMITATIONS: Lack of meta-analysis, because there were not enough articles to be analyzed on any given outcome of interest, neither under the same study design. CONCLUSIONS: Results of individual studies indicated that dance classes did not active 50% of the total time at MVPA levels. This may be related to the absence of improvements in daily/weekly MVPA before and after dance interventions. VO2 and HR attained peaks of moderateto vigorous intensity during dance classes, suggesting that the structure of the classes may be manipulated to maintain longer periods at MVPA levels. Lack of data on cardiorespiratory fitness and metabolic outcomes limit conclusions on these parameters. IMPLICATIONS OF KEYS FINDS: Considering there are peaks of HR and VO2 during dance classes, we suggest that the structure of a dance class can be manipulate in order to induce cardiorespiratory and metabolic adaptations. Thus, dancing is a potential strategy to contribute with a healthy life style since the earliest ages. Prospero registration: CRD42020144609.

Effects of a Single Session of High- and Moderate-Intensity Resistance Exercise on Endothelial Function of Middle-Aged Sedentary Men.

Regular resistance exercise is associated with metabolic, neuromuscular and cardiovascular adaptations which improve quality of life and health. However, sedentary subjects have shown acute impairments in endothelial function after high-intensity resistance exercise. The aim of this study was to evaluate endothelial function in sedentary middle-aged men after a single session of resistance exercise at different intensities. Eleven sedentary middle-aged men (40.1 ± 3.9 years; 27.3 ± 1.4 kg/m2) underwent three different conditions of assessment: (1) single knee extension exercise at moderate intensity (MI) [4 sets of 12 repetitions at 50% of one repetition maximum (1RM) for each leg], (2) single knee extension exercise at high intensity (HI) (4 sets of 8 repetitions at 80% of 1RM for each leg), (3) resting for the control condition (CON). Flow-mediated dilation (FMD) was assessed before, 30 and 60 min after exercise. Plasma concentrations of endothelin-1 (ET-1), nitrites and nitrates (NOx) and thiobarbituric acid reactive substances (TBARS) were measured before, immediately after and 60 min after exercise. Blood pressure (BP) was measured prior to the experimental protocols, and in the following times: immediately following, and 2, 5, 10, 15, 30, and 60 min after exertion. There was a significant improvement in FMD 30 min after MI condition (12.5 ± 4.10 vs. 17.2 ± 3.9%; p = 0.016). NOx levels were significantly higher immediately after MI (6.8 ± 3.3 vs. 12.6 ± 4.2 µM; p = 0.007) and there was a significant increase in the concentration of ET-1 immediately after HI (20.02 ± 2.2 vs. 25.4 ± 2.1 pg/mL; p = 0.004). However, there was no significant difference for BP (MI vs. HI) and TBARS among the experimental conditions. Resistance exercise performed at moderate intensity improved vasodilatation via increases on NOx levels and FMD in sedentary middle-aged men.

Superior Effects of High-Intensity Interval vs. Moderate-Intensity Continuous Training on Endothelial Function and Cardiorespiratory Fitness in Patients With Type 1 Diabetes: A Randomized Controlled Trial.

This study aimed to compare the effect of high-intensity interval training (HIIT) with moderate-intensity continuous training (MCT) on endothelial function, oxidative stress and clinical fitness in patients with type 1 diabetes. Thirty-six type 1 diabetic patients (mean age 23.5 ± 6 years) were randomized into 3 groups: HIIT, MCT, and a non-exercising group (CON). Exercise was performed in a stationary cycle ergometers during 40 min, 3 times/week, for 8 weeks at 50-85% maximal heart rate (HRmax) in HIIT and 50% HRmax in MCT. Endothelial function was measured by flow-mediated dilation (FMD) [endothelium-dependent vasodilation (EDVD)], and smooth-muscle function by nitroglycerin-mediated dilation [endothelium-independent vasodilation (EIVD)]. Peak oxygen consumption (VO2peak) and oxidative stress markers were determined before and after training. Endothelial dysfunction was defined as an increase < 8% in vascular diameter after cuff release. The trial is registered at ClinicalTrials.gov, identifier: NCT03451201. Twenty-seven patients completed the 8-week protocol, 9 in each group (3 random dropouts per group). Mean baseline EDVD was similar in all groups. After training, mean absolute EDVD response improved from baseline in HIIT: + 5.5 ± 5.4%, (P = 0.0059), but remained unchanged in MCT: 0.2 ± 4.1% (P = 0.8593) and in CON: -2.6 ± 6.4% (P = 0.2635). EDVD increase was greater in HIIT vs. MCT (P = 0.0074) and CON (P = 0.0042) (ANOVA with Bonferroni). Baseline VO2peak was similar in all groups (P = 0.96). VO2peak increased 17.6% from baseline after HIIT (P = 0.0001), but only 3% after MCT (P = 0.055); no change was detected in CON (P = 0.63). EIVD was unchanged in all groups (P = 0.18). Glycemic control was similar in all groups. In patients with type 1 diabetes without microvascular complications, 8-week HIIT produced greater improvement in endothelial function and physical fitness than MCT at a similar glycemic control.

Dancing for Healthy Aging: Functional and Metabolic Perspectives.

CONTEXT: Dancing has been used as a form of exercise to improve functional and metabolic outcomes during aging. The field lacks randomized, clinical trials (RCTs) evaluating metabolic outcomes related to dance interventions, but dancing may be a form of exercise that could induce positive effects on the metabolic health of older adults. However, primary studies seem very heterogonous regarding the trial designs, characteristics of the interventions, the methods for outcomes assessments, statistical powers, and methodological quality. OBJECTIVE: The current research team intended to review the literature on the use of dance as a form of intervention to promote functional and metabolic health in older adults. Specifically, the research team aimed to identify and describe the characteristics of a large range of studies using dance as an intervention, summarizing them and putting them into perspective for further analysis. DESIGN: The research team searched the following data sources-MEDLINE, Cochrane Wiley, Clinical Trials.gov, the Physiotherapy Evidence Database (PEDRO), and the Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS)-for RCTs, quasi-experimental studies, and observational trials that compared the benefits of any style of dancing, combined with other exercises or alone, to nonexercising controls and/or controls practicing other types of exercise. SETTING: The study took place at the Federal University of Rio Grande do Sul (Porto Alegre, Brazil). PARTICIPANTS: Participants were aging individuals, >55 y, both with or without health conditions. INTERVENTIONS: Interventions should be supervised, taking form as group classes, in a dance setting environment. Dance styles were divided into 5 categories for the review: (1) cultural dances developed by groups of people to reflect the roots of a certain region, such as Greek dance; (2) ballroom dance (ie, dances with partners performed socially or competitively in a ballroom, such as foxtrot); (3) aerobic dance with no partner required, which mixes aerobic moves with dance moves; (4) dance therapies, whichare special dance programs including emotional and physical aspects; and (5) classical dances, which are dances with a unique tradition and technique, such as ballet or jazz dance. OUTCOME MEASURES: Studies needed to have evaluated functional and/or metabolic outcomes. Functional outcomes included (1) static and/or dynamic balance, (2) gait ability, (3) upper and/or lower muscle strength or power, (4) cardiorespiratory fitness, (5) flexibility, (6) risk of falls, and (7) quality of life. Metabolic outcomes included (1) lipid and glycemic profile; (2) systolic and diastolic blood pressure; (3) body composition; and (4) other specific cardiovascular risk factors or inflammatory or oxidative stress markers. RESULTS: The research team retrieved 1042 articles, with 88 full texts assessed for eligibility, and 50 articles included in the analysis. Of the analyzed studies, 22 were RCTs evaluating dancing vs controls, and 3 were RCTs evaluating dancing vs other exercise. Regarding the participants of the reviewed studies: (1) 31 evaluated healthy individuals, (2) 7 evaluated patients suffering from Parkinson's disease, (3) 4 evaluated postmenopausal women, (4) 2 evaluated obese women, (5) 2 evaluated patients with chronic heart failure, (6) 1 evaluated frail older adults, (7) 1 evaluated individuals with visual impairments, (8) 1 evaluated persons with metabolic syndrome, and (9) 1 evaluated individuals with severe pain in the lower extremities. Regarding the interventions, most interventions were 12 wk long, 3 ×/wk, for 60 min each session. The dance styles most used were ballroom and cultural dances. Regarding the outcomes, functional and metabolic benefits were described in most of the included studies. Balance was the functional outcome most often assessed. CONCLUSIONS: Any dance style can induce positive functional adaptations in older adults, especially related to balance. Metabolic improvements may also be a result of dancing; however, more RCTs are needed. Dancing may be a potential exercise intervention to promote health-related benefits for aging individuals.

Acute and residual effects of aerobic exercise on fructose-induced postprandial lipemia on lean male subjects.

PURPOSE: The addition of fructose to one or more meals daily may lead to increased postprandial lipemia (PPL). Aerobic exercise has been successful in preventing those increases; however, the duration of exercise effects is still unknown. The aim of this study was to evaluate the acute and residual effects of aerobic exercise and fructose ingestion on PPL. METHODS: Twelve young and sedentary men completed a crossover blinded randomized trial. On day 0, they performed 45 min of aerobic exercise at 60% of VO2peak, or 45 min of resting. On day 1, they received a high-fat meal together with one of the following conditions: (a) a fructose-rich beverage (FRUCT), or (b) exercise performed 13 h before the fructose-rich beverage ingestion (FRUCTEX), or (c) a dextrose-based beverage (DEX). On day 2, all subjects received a high-fat meal plus dextrose. Five blood samples were taken on days 1 and 2, to measure triglycerides (TG), HDL cholesterol, VLDL, total cholesterol (TC), glucose and insulin. RESULTS: On day 1, the delta of the TG peak was higher for FRUCT compared to DEX condition (+ 73.7%; p = 0.019). Total area under the curve (AUC) of TG was lower on the condition FRUCTEX compared to FRUCT (+ 30%; p = 0.001). There was no effect of the beverages or the exercise on VLDL, TC, HDL and non-HDL cholesterol (p > 0.05). There were no differences found in any of the parameters assessed on day 2 (p > 0.05). CONCLUSIONS: Fructose consumption (0.5 g/kg) severely increased postprandial TG on day 1, but not on day 2. Previous exercise performance could lead to ~ 30% reduction on the AUC of postprandial TG in 13 h, but not after 37 h followed by fructose consumption. The regularity of physical exercise practice seems to be essential to promote a constant hypolipemic effect.

Association of l-Arginine Supplementation with Markers of Endothelial Function in Patients with Cardiovascular or Metabolic Disorders: A Systematic Review and Meta-Analysis.

l-Arginine supplementation is a potential therapy for treating cardiovascular and metabolic diseases. However, the use of distinct l-arginine sources, intervened populations, and treatment regimens may have yielded confusion about their efficacy. This research constitutes a systematic review and meta-analysis summarizing the effects of l-arginine supplementation compared to placebo in individuals with cardiovascular disease (CVD), obesity, or diabetes. Eligibility criteria included randomized clinical trials and interventions based on oral supplementation of l-arginine with a minimum duration of three days; comparison groups consisted of individuals with the same disease condition receiving an oral placebo substance. The primary outcome was flow-mediated dilation, and secondary outcomes were nitrite/nitrate (NOx) rate and asymmetric dimethylarginine (ADMA). Statistical heterogeneity among studies included in the meta-analyses was assessed using the inconsistency index (I2). Fifty-four full-text articles from 3761 retrieved references were assessed for eligibility. After exclusions, 13 studies were included for data extraction. There was no difference in blood flow after post-ischemic hyperemia between the supplementation of l-arginine and placebo groups before and after the intervention period (standardized mean difference (SMD) = 0.30; 95% confidence intervals (CIs) = -0.85 to 1.46; I2 = 96%). Sensitivity analysis showed decreased heterogeneity when the studies that most favor arginine and placebo were removed, and positive results in favor of arginine supplementation were found (SMD = 0.59; 95% CIs = 0.10 to 1.08; I2 = 75%). No difference was found in meta-analytical estimates of NOx and ADMA responses between arginine or placebo treatments. Overall, the results indicated that oral l-arginine supplementation was not associated with improvements on selected variables in these patients (PROSPERO Registration: CRD42017077289).

Effects of dancing compared to walking on cardiovascular risk and functional capacity of older women: A randomized controlled trial.

INTRODUCTION: Aging is characterized by reductions in lean mass simultaneously to increases in visceral adipose tissue, elevating cardiovascular risk (CVR) and physical dependence. Dancing has been recommended for improving fall-risk and CVR, however, comparisons with traditional exercises are limited. This study aimed to compare the effects of dancing with walking on CVR and functionality of older women. METHODS: Thirty sedentary women (65 ±â€¯5 years, BMI 27 ±â€¯4 kg/m2) were randomized into three groups (n = 10/group): dancing, walking or stretching (active control). All interventions lasted 8 weeks (60 min sessions): dancing/walking 3×/week, stretching 1×/week. Dancing: several styles, no partner. Walking: treadmill, 60% peak oxygen consumption (VO2peak). Stretching: large muscle groups, no discomfort. Before and after interventions assessments: VO2peak (primary outcome), total cholesterol, HDL-C, LDL-C, glucose, insulin, CRP, TNF-α, waist and hip circumferences, visceral adipose tissue (VAT), muscle thickness, maximal muscle strength/power, static and dynamic balance, gait ability, flexibility, chair-raise and level of physical activity (PA). STATISTICS: generalized estimating equations, post-hoc LSD (p < 0.05), SPSS 22.0. RESULTS: (Mean-CI): (before vs after): group vs time interaction showed increases in VO2peak (mL·kg-1·min-1) for dancing 23.3 (20.8-25.8) vs 25.6 (23.4-27.8), and walking 23.4 (21.3-25.5) vs 27.0 (25.4-28.6), with no differences for stretching 23.5 (21.3-25.7) vs 23.0 (21.0-24.9). Lower body muscle power and static balance also improved for dancing and walking, but not for stretching. Main time effect showed improvements in CRP, TNF-α, LDL-C, HDL-C, VAT, waist, hip, chair raise, flexibility and level of daily PA for all groups. CONCLUSION: Dancing induced similar increases in VO2peak, lower body muscle power and static balance as walking, while the stretching group remained unchanged. Pooled effects showed improvements in body composition, lipid and inflammatory profile, which are supported by increased PA levels. TRIAL REGISTRATION: NCT03262714.

Heat-induced extracellular HSP72 release is blunted in elderly diabetic people compared with healthy middle-aged and older adults, but it is partially restored by resistance training.

Recent evidence suggests that the anti-inflammatory heat shock response (HSR) is reduced in aging and diabetes. In this study we compared HSR between healthy middle-aged adults, healthy elderly and type 2 diabetic (T2DM) elderly, and tested whether resistance training (RT) could improve the HSR in T2DM group. Thirty sedentary participants volunteered for this study. HSR (assessed as the capacity to export HSP72 during heat stress) was measured in the blood and compared between the groups. HSR was similar between healthy middle-aged and healthy elderly volunteers, but diminished in elderly T2DM (p < 0.001). Hence, T2DM subjects (n = 12) were submitted to a 12-week RT program, because exercise is a physiological HSR inducer. HSR, cytokines, metabolic parameters and visceral adipose tissue (VAT) were measured before and after the RT. Remarkably, VAT was negatively correlated with HSR (r = - 0.49, p < 0.01) while RT improved the HSR and reduced inflammation [TNF-α: from 51.5 ±â€¯9 to 40.7 ±â€¯4 pg/mL and TNF-α/IL-10 ratio: from 1.55 ±â€¯0.3 to 1.16 ±â€¯0.2 (p < 0.001)], without affecting other parameters. All together, these findings confirm the hypothesis that the anti-inflammatory HSR is depressed in elderly diabetic people, but can be partially restored by RT.

Effects of Two Combined Exercise Designs Associated With High-Fat Meal Consumption on Postprandial Lipemia, Insulinemia, and Oxidative Stress.

Farinha, JB, Macedo, CEO, Rodrigues-Krause, J, Krüger, RL, Boeno, FP, Macedo, RCO, Queiroz, JN, Teixeira, BC, and Reischak-Oliveira, A. Effects of two combined exercise designs associated with high-fat meal consumption on postprandial lipemia, insulinemia, and oxidative stress. J Strength Cond Res 32(5): 1422-1430, 2018-Impaired postprandial lipemia (PPL) response after the consumption of a high-fat meal (HFM) is linked to diabetes, oxidative stress, and cardiovascular events. The aim of this study was to investigate lipid and glucose metabolism and oxidative stress responses of 2 different combined exercise designs associated with HFM consumption. Eleven healthy and physically active men (27.36 ± 5.04 years) participated in this study. After the pretrial visits, participants were randomly assigned to perform 2-day trials in 3 different conditions (interspaced by at least 1 week): resting (REST), circuit combined exercise (CIRC), or traditional combined exercise (COMB), on the evening of day 1. On the morning of day 2, an HFM was provided and blood samples were obtained before and after 1, 3, and 5 hours of HFM consumption. No differences were found with respect to glucose, thiobarbituric acid-reactive substances, or total thiol levels in between time points or conditions. One-way analysis of variance demonstrated a difference between REST and CIRC (p = 0.029; reduction of 35.29%) and between REST and COMB (p = 0.041; reduction of 33.41%) conditions with incremental area under the curve (iAUC) for triacylglycerol levels. A difference between REST and CIRC (p = 0.03; reduction of 34.22%) conditions in terms of iAUC for insulin was also found. Both CIRC and COMB exercise designs can reduce PPL associated with HFM consumption. Moreover, CIRC reduces the iAUC for insulin, suggesting additional benefits for prescribing this type of exercise.

Cardiorespiratory Considerations in Dance: From Classes to Performances.

When attempting to ascertain dancers' fitness levels, essential parameters, such as aerobic and anaerobic capacity, muscular power and strength, flexibility, and body composition, must be considered. Dance is characterized as an intermittent type of exercise, demanding energy from different metabolic pathways (aerobic and anaerobic, lactic or alactic). A dancer's maximum aerobic capacity (ranging from 37 to 57 ml·kg(-1)·min(-1)) is related to his or her dance style, gender, level of technical ability, and status in a dance company. However, dancers' cardiorespiratory requirements during dance classes (essentially designed for the development of technical skills) are significantly lower than during dance performances, indicating that there is a divergence between dance training and performance with regard to demands on dancers' physical fitness. It follows that supplementary fitness training is needed in order to optimize dancers' technical and artistic performance and to reduce the incidence of injury. Traditional aerobic and strength training have been proposed to cover dancers' lack of conditioning; however, it seems likely that high-intensity interval training would more properly meet the requirements of today's choreography. Therefore, with an approach that applies basic exercise physiology to dance characteristics, this review covers the following topics: 1. dance as physical exercise; 2. dancers' aerobic capacity; 3. cardiorespiratory demands of dance classes and performances; 4. supplementary fitness training for dancers; and 5. fitness testing and assessment for dancers.

Oxygen consumption and heart rate responses to isolated ballet exercise sets.

Ballet stage performances are associated with higher cardiorespiratory demand than rehearsals and classes. Hence, new interest is emerging to create periodized training that enhances dancers' fitness while minimizing delayed exercise-induced fatigue and possible injuries. Finding out in what zones of intensity dancers work during different ballet movements may support the use of supplemental training adjusted to the needs of the individual dancer. Therefore, the main purpose of this study was to describe dancers' oxygen consumption (VO2) and heart rate (HR) responses during the performance of nine isolated ballet exercise sets, as correlated with their first and second ventilatory thresholds (VT1 and VT2). Twelve female ballet dancers volunteered for the study. Their maximum oxygen consumption (VO2max), VT1, and VT2 were determined by use of an incremental treadmill test. Nine sets of ballet movements were assessed: pliés, tendus, jetés, rond de jambes, fondus, grand adage (adage), grand battements, temps levés, and sautés. The sets were randomly executed and separated by 5 minute rest periods. ANOVA for repeated measurements followed by the Bonferroni Post-hoc test were applied (p < 0.05). VO2 responses were as follows: pliés (17.6 ± 1.6 ml·kg(-1)·min(-1)); tendus and adage were not significantly greater than VT1; rond de jambes (21.8 ± 3.1 ml·kg(-1) ·min(-1)); fondus and jetés were higher than VT1 and the previous exercises; grand battements (25.8 ± 2.9 ml·kg(-1)·min(-1)) was greater than all the other exercises and VT1; and VT2 was significantly higher than all ballet sets. This stratification followed closely, but not exactly, the variation in HR. For example, rond de jambes (156.8 ± 19 b·min(-1)) did not show any significant difference from all the other ballet sets, nor VT1 or VT2. It is concluded that the workloads of isolated ballet sets, based on VO2 responses, vary between low and moderate aerobic intensity in relation to dancers' VT1 and VT2. However, ballet set workloads may be higher when based on HR responses, due to the intermittent and isometric components of dance.

Ballet dancers cardiorespiratory, oxidative and muscle damage responses to classes and rehearsals.

This study aimed to describe and compare ballet dancers' cardiorespiratory responses, muscle damage and oxidative stress levels during a ballet class (practice of isolated ballet exercises performed with barre/hand-rail support and across-the-floor movements to improve technical skills) and rehearsal (practice of ballet choreography involving technical-artistic skills to improve dancers' performance for shows). The 12 advanced female ballet dancers undertook three exercise sessions: maximum effort test, class and rehearsal. Heart rate (HR) and oxygen consumption (VO2) were continuously measured. Lactate was determined before 15 min and after class and rehearsal. Blood was sampled pre, post and 48 h after class and rehearsal for creatine kinase (CK), lipid peroxides (LPO) and glutathione analysis (GSSG/GSH). Class was of lower intensity than rehearsal as shown by VO2, HR and lactate values: VO2 (mL.kg(-1).min(-1)): 14.5±2.1 vs. 19.1±1.7 (p < 0.001); HR (bpm.min(-1)): 145.7±17.9 vs. 174.5±13.8 (p < 0.001); lactate (mmol.L(-1)): 4.2±1.1 vs. 5.5±2.7 (p = 0.049). CK (IU) increased following class and rehearsal, remaining high 48 h after: class (pre = 109.3±48.5; post = 144±60; 48 h = 117.2±64.6); rehearsal (pre = 78.6±52.1; post = 122±70.7; 48 h = 104.9±89.5). LPO (µM) increased from pre-class (1.27±0.19) to post-class (1.41±0.19) and went down after 48 h (1.20±0.22). No LPO time-course changes followed the rehearsal. GSSG/GSH decreased 48 h after class and rehearsal. Greater increases in LPO post-class suggest it promotes CK release by an oxidative membrane-damage mechanism. Physiological increases of LPO and CK in class indicate it prepares the dancers for exercise-induced oxidative stress and muscle damage during rehearsals. Ballet dancers' muscle damage and oxidative stress responses seem not to be dependent on exercise intensity based on VO2 responses.

Effects of L-arginine supplementation on blood flow, oxidative stress status and exercise responses in young adults with uncomplicated type I diabetes.

BACKGROUND AND AIMS: Vascular disease is the principal cause of death and disability in patients with diabetes, and endothelial dysfunction seems to be the major cause in its pathogenesis. Since L-arginine levels are diminished in conditions such as type 1 and type 2 diabetes, in this work we aimed to verify the effects of L-arginine supplementation (7 g/day) over the endothelial function and oxidative stress markers in young male adults with uncomplicated type 1 diabetes. We also investigated the influences of L-arginine administration on vascular/oxidative stress responses to an acute bout of exercise. METHODS: Ten young adult male subjects with uncomplicated type 1 diabetes and twenty matched controls volunteered for this study. We analysed the influence of L-arginine supplementation (7 g/day during 1 week) over lower limb blood flow (using a venous occlusion plethysmography technique), oxidative stress marker (TBARS, Carbonyls), anti-oxidant parameters (uric acid and TRAP) and total tNOx in rest conditions and after a single bout of submaximal exercise (VO2 at 10 % below the second ventilatory threshold). Data described as mean ± standard error (SE). Alpha level was P < 0.05. RESULTS: Glycaemic control parameters were altered in type 1 diabetic subjects, such as HbA1c (5.5 ± 0.03 vs. 8.3 ± 0.4 %) and fasted glycaemia (94.8 ± 1.4 vs. 183 ± 19 mg/dL). Oxidative stress/damage markers (carbonyls and TBARS) were increased in the diabetic group, while uric acid was decreased. Rest lower limb blood flow was lower in type 1 diabetic subjects than in healthy controls (3.53 ± 0.35 vs. 2.66 ± 0.3 ml 100 ml⁻¹ min⁻¹). L-Arginine supplementation completely recovered basal blood flow to normal levels in type 1 diabetics' subjects (2.66 ± 0.3 to 4.74 ± 0.86 ml 100 ml⁻¹ min⁻¹) but did not interfere in any parameter of redox state or exercise. CONCLUSION: Our findings highlight the importance of L-arginine for the improvement of vascular function in subjects with diabetes, indicating that L-arginine supplementation could be an essential tool for the treatment for the disease complications, at least in non-complicated diabetes. However, based on our data, it is not possible to draw conclusions regarding the mechanisms by which L-arginine therapy is inducing improvements on cardiovascular function, but this important issue requires further investigations.