Chronic aerobic exercise prevents high-fructose diet-induced impairment in blood pressure in healthy young adults: a double-blind, randomised clinical trial.

The purpose of the study was to verify the effect of 4 weeks of a high-fructose diet (HFD) associated with aerobic training on the risk factors for cardiometabolic diseases. Twenty-one young adults were randomised into three groups: HFD (HFD: 1 g/kg body weight of fructose/day), high-glucose diet (HGD: 1 g/kg body weight of glucose/day) and high-fructose diet and exercise (HFDE: 1 g/kg body weight of fructose/day + 3 weekly 60-minute sessions of aerobic exercise). Before and after the 4 weeks of the intervention, blood samples were taken and flow-mediated dilatation, insulin resistance index, pancreatic beta cell functional capacity index, insulin sensitivity index and 24-h blood pressure were evaluated. HFD showed an increase in uric acid concentrations (P = 0·040), and HGD and HFDE groups showed no changes in this outcome between pre- and post-intervention; however, the HFDE group showed increased uric acid concentrations from the middle to the end of the intervention (P = 0·013). In addition, the HFD group showed increases in nocturnal systolic blood pressure (SBP) (P = 0·022) and nocturnal diastolic blood pressure (DBP) (P = 0·009). The HGD group exhibited decreases in nocturnal SBP (P = 0·028) and nocturnal DBP (P = 0·031), and the HFDE group showed a decrease in 24-h SBP (P = 0·018). The consumption of 1 g/kg of fructose per day may increase uric acid concentrations and blood pressure in adults. Additionally, aerobic exercises along with fructose consumption attenuate changes in uric acid concentrations and prevent impairment in nocturnal blood pressure.

Cardiometabolic health profile of young girls with aesthetic professions.

BACKGROUND: In the literature, professions that impose body standards for daily performance are designated as non-conventional professions (i.e. models, athletes, ballet dancers), with great emphasis on the female population. More than a job, it becomes a lifestyle to those inserted in this environment, thus, thousands of children and adolescents seek inclusion and success in these professions due to financial and media gains. Such professions are associated with several health-related risk factors. The purpose of this study was to identify and compare among physical fitness levels, cardiometabolic health markers, mental health and dietary habits in non-conventional professions. METHODS: The sample consisted of 41 female individuals aged between 14 and 24 years, allocated into four groups, control group composed by university students (UG = 11), models (MG = 11), ballet dancers (BG = 11), and athletes' group (AG = 8). Physical fitness outcomes (cardiorespiratory fitness, flexibility, maximal dynamic strength, muscular endurance and body composition); biochemical outcomes (high-density lipoprotein [HDL], low-density lipoprotein [LDL], total cholesterol [TC], fasting glucose [FG], fasting insulin [FI], C-reactive protein [CRP]), diet quality and mental health were evaluated. RESULTS: No impairments were observed in the health markers evaluated among groups, both for health-related physical fitness and biochemical outcomes. However, low levels of bone mineral density (BMD) were observed. Even with statistically significant differences between the groups for chronological age (p = 0.002), menarche (p = 0.004), career length (p = 0.001), height (p = 0.001), body mass index (p = 0.018), waist-to-height ratio (p < 0.001), %Fat (p = 0.020), VO2peak (p = 0.020), maximal dynamic strength of knee extensors (p = 0.031) and elbow flexors (p = 0,001) and flexibility (p < 0.001), all these values are within the normal range for health. CONCLUSION: The professions analyzed do not seem to interfere in the physical fitness and cardiometabolic health of the girls assessed. However, we identified that exposure to these profession can impair mental health (depressive symptoms in 100% of participants) and body composition (BMD 63% of participants).

Acute moderate-intensity aerobic exercise promotes purinergic and inflammatory responses in sedentary, overweight and physically active subjects.

NEW FINDING: What is the central question of this study? How does moderate-intensity aerobic exercise affect the behaviour of purinergic enzymes in sedentary, overweight and physically active subjects? What is the relationship between purinergic and inflammatory responses triggered by exercise? What is the main finding and its importance? Moderate-intensity aerobic exercise modifies the activity of purinergic enzymes and the levels of nucleotides and nucleosides. These results are similar in subjects with different biological characteristics. 5'-Nucleotidase activity and adenosine levels are associated with inflammatory responses. This study suggests that a purinergic pathway is related to the inflammatory responses triggered by exercise. ABSTRACT: Purinergic signalling is a mechanism of extracellular communication that modulates events related to exercise, such as inflammation and coagulation. Herein, we evaluated the effects of acute moderate-intensity exercise on the activities of purinergic enzymes and plasma levels of adenine nucleotides in individuals with distinct metabolic characteristics. We analysed the relationship between purinergic parameters, inflammatory responses and cardiometabolic markers. Twenty-four healthy males were assigned to three groups: normal weight sedentary (n = 8), overweight sedentary (n = 8) and normal weight physically active (n = 8). The volunteers performed an acute session of moderate-intensity aerobic exercise on a treadmill at 70% of V̇O2peak ; blood samples were drawn at baseline, immediately post-exercise and at 1 h post-exercise. Immediately post-exercise, all subjects showed increases in ATP, ADP, AMP and p-nitrophenyl thymidine 5'-monophosphate hydrolysis, while AMP hydrolysis remained increased at 1 h after exercise. High-performance liquid chromatography analysis demonstrated lower levels of ATP and ADP at post- and 1 h post-exercise in all groups. Conversely, adenosine and inosine levels increased at post-exercise, but only adenosine remained augmented at 1 h after exercise in all groups. With regard to inflammatory responses, the exercise protocol increased tumour necrosis factor α (TNF-α) and interleukin 8 (IL-8) concentrations in all subjects, but only TNF-α remained elevated at 1 h after exercise. Significant correlations were found between the activity of 5'-nucleotidase, adenosine levels, V̇O2peak , triglyceride, TNF-α and IL-8 levels. Our findings suggest a purinergic signalling pathway that participates, at least partially, in the inflammatory responses triggered by acute moderate-intensity exercise. The response of soluble nucleotidases to acute moderate exercise appears to be similar between subjects of different biological profiles.

Time-restricted eating and circadian rhythms: the biological clock is ticking.

Meal timing may be a critical modulator of health outcomes due to complex interactions between circadian biology, nutrition and human metabolism. As such, approaches that aim to align food consumption with endogenous circadian rhythms are emerging in recent years. Time-restricted eating (TRE) consists of limiting daily nutrient consumption to a period of 4 to 12 hours in order to extend the time spent in the fasted state. TRE can induce positive effects on the health of individuals with overweight and obesity, including sustained weight loss, improvement in sleep patterns, reduction in blood pressure and oxidative stress markers and increased insulin sensitivity. However, it is not fully clear whether positive effects of TRE are due to reduced energy intake, body weight or the truncation of the daily eating window. In addition, null effects of TRE in some populations and on some parameters of cardiometabolic health have been documented. Some evidence indicates that greater promotion of health via TRE may be achieved if the nutrient intake period occurs earlier in the day. Despite some promise of this dietary strategy, the effects of performing TRE at different times of the day on human cardiometabolic health, as well as the safety and efficacy of this dietary approach in individuals with cardiometabolic impairments, need to be evaluated in additional controlled and long-term studies.

Effect of photobiomodulation therapy on performance and running economy in runners: A randomized double-blinded placebo-controlled trial.

The objective of this study was to evaluate effects of photobiomodulation therapy (PBMT) on the 3000 m running performance (primary outcome), running economy (RE), metabolic cost and ratings of perceived exertion during running (secondary outcomes). Twenty male endurance athletes performed 4-min treadmill rectangular test at 12 km.h-1 monitored by a gas analyser. After that, PBMT or placebo in each lower limb was applied, followed performed a maximum test of 3000 m. Immediately after 3000 m test, the athletes repeated the treadmill test. Another application of PBMT/placebo was done after the treadmill test, and athletes went back to the laboratory 24 h later to repeat the treadmill test. After a 72 h interval, athletes repeated all procedures with another treatment intervention (PBMT/placebo). Athletes performed the 3000 m running test ~7s faster when treated with PBMT with similar effort score compared placebo condition. The RE remains unchanged immediately post 3000 m running test, nonetheless RE measured post-24 h improved by 5% with PBMT application without changes in metabolic cost. The PBMT pre- and post-conditioning enhanced the 3000 m running performance and improved RE 24 h following the 3000 m test. However, no changes on ratings of perceived exertion and metabolic cost with the application of PBMT.

Redox balance during exercise in the heat in healthy adults: A systematic review.

BACKGROUND: Hyperthermia, induced by exercise in the heat, alters the redox status. The physiological significance of these observations remains uncertain but may justify why the consequences of exercising in the heat span from positive health adaptations to negative and even lethal outcomes. Here, we conducted a systematic review to investigate the redox responses during acute exercise in the heat in healthy adults. METHODS: We searched MEDLINE, Cochrane Wiley, ClinicalTrials.gov, PEDRO and LILACS for clinical trials investigating pro- and antioxidant responses to exercise associated with hyperthermia and/or sweat-induced dehydration in healthy young individuals. Two independent reviewers extracted data and assessed the quality of the included studies. RESULTS: A total of 1,014 records were selected, nine full papers were evaluated for eligibility, and eight studies met the inclusion criteria. Overall, results show that hyperthermia promotes oxidative stress both at the tissue level and in the circulation. Exercising in the heat heightens endogenous antioxidant defense systems, attenuating the negative effects of hyperthermia on oxidative damage. Studies also indicate that sweat-induced dehydration promotes oxidative stress, which is attenuated by rehydration. CONCLUSION: These findings suggest that changes in redox status play a role in determining whether an acute bout of exercise in the heat lead to adaptive or maladaptive outcomes.

Maturity status effects on torque and muscle architecture of young soccer players.

This study investigated the effects of maturity status on knee extensor torque and vastus lateralis architecture of young soccer players. Thirty-four males aged 13-18 years were divided into two groups: pubescent (PUB, n = 15) and postpubescent (POSP, n = 19). Torque by angle interaction was established for absolute [F(2.649, 84.771) = 9.066, p < 0.05] and relative to body mass [F(2.704, 86.533) = 4.050, p < 0.05] isometric torque with the POSP group showing greater values. Muscle volume torque-angle relationship was similar between groups. Absolute, relative to body mass, and relative to muscle volume concentric and eccentric torque-velocity relationship showed a non-significant interaction but a significant group effect in favour the POSP group for absolute and concentric torque relative to body mass. Torque-angle and torque-velocity relationship normalized by body mass allometric exponents showed a non-significant interactions and group effects. Muscle thickness (3.6 ± 0.6 vs. 3.8 ± 0.6 cm), fascicle length (8.3 ± 1.4 vs. 8.9 ± 1.6 cm) and pennation angle (15.0 ± 2.3 vs. 14.3 ± 3.2 degrees) was similar between PUB and POSP groups, respectively. Maturity status did not show a significant effect on muscle architecture and on isometric and dynamic torques when allometrically normalized.

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.

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.

Effects of fructose consumption on postprandial TAG: an update on systematic reviews with meta-analysis.

The aim of this study was to re-examine the chronic effect (>7 d) of fructose consumption on postprandial TAG, in adolescents and adults. The research was carried out in March 2017 and used different electronic databases, such as Medline ® (Pubmed®), Embase® and Cochrane. The review considered clinical trials (parallel or crossed) that evaluated the effect of fructose consumption for a period longer than 7 d, in humans. Two investigators independently performed data extraction. The outcome was the absolute delta of TAG concentration in a 4-h postprandial period. The results were presented with delta mean difference between treatments with 95 % CI. The calculations were made based on random-effect models. Statistical heterogeneity of treatment effects between studies was assessed by Cochrane's 'Q Test' and 'I 2' inconsistency test. The meta-analysis of the twelve selected interventions (n 318) showed that fructose generated larger variation (δ) of TAG concentrations during the postprandial period, compared with other carbohydrates (mean difference: 8·02 (95 % CI 0·46, 15·58) mg/dl (0·09 (95 % CI 0·01, 0·18) mmol/l); I 2: 74 %). High heterogeneity was generated almost exclusively by one study, and its withdrawal did not alter the result. We concluded that chronic consumption of fructose (>7 d) has a negative role on postprandial TAG in healthy adolescents and adults, as well as in overweight/obese individuals, but not in diabetics.

Low-level laser therapy improves the VO2 kinetics in competitive cyclists.

Some evidence supports that low-level laser therapy (LLLT) reduces neuromuscular fatigue, so incrementing sports performance. A previous randomized controlled trial of our group showed increased exercise tolerance in male competitive cyclists treated with three different LLLT doses (3, 6, and 9 J/diode; or 135, 270, and 405 J/thigh) before time-to-exhaustion cycling tests. Now, the present study was designed to evaluate the effects of these LLLT doses on the VO2 kinetics of athletes during cycling tests. Twenty male competitive cyclists (29 years) participated in a crossover, randomized, double-blind, and placebo-controlled trial. On the first day, the participants performed an incremental cycling test to exhaustion to determine maximal oxygen uptake (VO2MAX) and maximal power output (POMAX), as well as a familiarization with the time-to-exhaustion test. In the following days (2 to 5), all participants performed time-to-exhaustion tests at POMAX. Before the exhaustion test, different doses of LLLT (3, 6, and 9 J/diode; or 135, 270, and 405 J/thigh, respectively) or placebo were applied bilaterally to the quadriceps muscle. All exhaustion tests were monitored online by an open-circuit spirometry system in order to analyze the VO2 amplitude, VO2 delay time, time constant (tau), and O2 deficit. Tau and O2 deficit were decreased with LLLT applications compared to the placebo condition (p < 0.05). No differences (p > 0.05) were found between the experimental conditions for VO2 amplitude and VO2 delay time. In conclusion, LLLT decreases tau and O2 deficit during time-to-exhaustion tests in competitive cyclists, and these changes in VO2 kinetics response can be one of the possible mechanisms to explain the ergogenic effect induced by LLLT.

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.

Altered extracellular ATP, ADP, and AMP hydrolysis in blood serum of sedentary individuals after an acute, aerobic, moderate exercise session.

Nucleotidases participate in the regulation of physiological and pathological events, such as inflammation and coagulation. Exercise promotes distinct adaptations, and can influence purinergic signaling. In the present study, we investigated soluble nucleotidase activities in the blood serum of sedentary young male adults at pre- and post-acute moderate aerobic exercise. In addition, we evaluated how this kind of exercise could influence adenine nucleotide concentrations in the blood serum. Sedentary individuals were submitted to moderate aerobic exercise on a treadmill; blood samples were collected pre- and post-exercise, and serum was separated for analysis. Results showed increases in ATP, ADP, and AMP hydrolysis post-exercise, compared to pre-exercise values. The ecto-nucleotide pyrophosphatase/phosphodiesterase was also evaluated, showing an increased activity post-exercise, compared to pre-exercise. Purine levels were analyzed by HPLC in the blood serum, pre- and post-exercise. Decreased levels of ATP and ADP were found post-exercise, in contrast with pre-exercise values. Conversely, post-exercise levels of adenosine and inosine increased compared to pre-exercise levels. Our results indicate an influence of acute exercise on ATP metabolism, modifying enzymatic behavior to promote a protective biological environment.

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.

The effect of prior walking on coronary heart disease risk markers in South Asian and European men.

PURPOSE: Heart disease risk is elevated in South Asians possibly due to impaired postprandial metabolism. Running has been shown to induce greater reductions in postprandial lipaemia in South Asian than European men, but the effect of walking in South Asians is unknown. METHODS: Fifteen South Asian and 14 white European men aged 19-30 years completed two, 2-day trials in a randomised crossover design. On day 1, participants rested (control) or walked for 60 min at approximately 50 % maximum oxygen uptake (exercise). On day 2, participants rested and consumed two high-fat meals over a 9-h period during which 14 venous blood samples were collected. RESULTS: South Asians exhibited higher postprandial triacylglycerol [geometric mean (95 % confidence interval) 2.29 (1.82 to 2.89) vs. 1.54 (1.21 to 1.96) mmol L(-1) h(-1)], glucose [5.49 (5.21 to 5.79) vs. 5.05 (4.78 to 5.33) mmol L(-1) h(-1)], insulin [32.9 (25.7 to 42.1) vs. 18.3 (14.2 to 23.7) µU mL(-1) h(-1)] and interleukin-6 [2.44 (1.61 to 3.67) vs. 1.04 (0.68 to 1.59) pg mL(-1) h(-1)] than Europeans (all ES ≥ 0.72, P ≤ 0.03). Between-group differences in triacylglycerol, glucose and insulin were not significant after controlling for age and percentage body fat. Walking reduced postprandial triacylglycerol [1.79 (1.52 to 2.12) vs. 1.97 (1.67 to 2.33) mmol L(-1) h(-1)] and insulin [21.0 (17.0 to 26.0) vs. 28.7 (23.2 to 35.4) µU mL(-1) h(-1)] (all ES ≥ 0.23. P ≤ 0.01), but group differences were not significant. CONCLUSIONS: Healthy South Asians exhibited impaired postprandial metabolism compared with white Europeans, but these differences were diminished after controlling for potential confounders. The small-moderate reduction in postprandial triacylglycerol and insulin after brisk walking was not different between the ethnicities.

High-volume resistance training reduces postprandial lipaemia in postmenopausal women.

The aim of this study was to compare the effects of 11 weeks of low-volume resistance training (LVRT) and high-volume resistance training (HVRT) on muscle strength, muscle thickness (MT), and postprandial lipaemia (PPL) in postmenopausal women. Thirty-six healthy and untrained postmenopausal women (age, 58.9 ± 5.8 years; 68.6 ± 10.3 kg; and BMI, 26.9 ± 4.8 kg · m(-2)) participated in resistance training 3× per week for 11 weeks (HVRT = 12; LVRT = 13; and control group = 11). Biochemical variables, both pretraining and post-training, were evaluated 16 h after the administration of an oral fat tolerance test (OFTT) and metabolic variable during [energy expenditure (EE)] and after training session [excess postexercise oxygen consumption (EPOC)]. Muscle strength (1 RM) and MT were also calculated, and no significant differences were observed between the groups for PPL (mmol · L(-1) per 5 h) as measured by glucose, high-density lipoprotein, low-density lipoprotein, and total cholesterol. EE total (EE + EPOC; 6.12 ± 1.21 MJ vs. 2.26 ± 0.85 MJ), resting fat oxidation (5.52 ± 1.69 g · h(-1) vs. 4.11 ± 1.12 g · h(-1)); MT (vastus medialis, 21.4 ± 1.8 mm vs. 18.4 ± 1.2 mm and vastus lateralis 22.3 ± 1.2 mm vs. 20.8 ± 1.3 mm); triacylglycerol (TAG) 0, 1, 2, 4; and 5 h after OFTT, TAG area under the curve (AUC) (5.79 ± 0.42 vs. 7.78 ± 0.68), and incremental AUC (-46.21 ± 14.42% vs. 7.78 ± 4.68%) were all significantly different post-training for HVRT versus LVRT, respectively (P < 0.05). The results of this investigation suggest that HVRT reduces PPL in postmenopausal women.

Effects of resistance training on heat shock response (HSR), HSP70 expression, oxidative stress, inflammation, and metabolism in middle-aged people.

Resistance training (RT) can increase the heat shock response (HSR) in the elderly. As middle-aged subjects already suffer physiological declines related to aging, it is hypothesized that RT may increase the HSR in these people. To assess the effects of resistance training on heat shock response, intra and extracellular HSP70, oxidative stress, inflammation, body composition, and metabolism in middle-aged subjects. Sixteen volunteers (40 - 59 years) were allocated to two groups: the trained group (n = 7), which performed 12 weeks of RT; and the physically inactive-control group (n = 9), which did not perform any type of exercise. The RT program consisted of 9 whole-body exercises (using standard gym equipment) and functional exercises, carried out 3 times/week. Before and after the intervention, body composition, muscle mass, strength, functional capacity, and blood sample measurements (lipid profile, glucose, insulin, oxidative damage, TNF-α, the HSR, HSP70 expression in leukocytes, and HSP72 in plasma) were performed. The HSR analysis demonstrated that this response is maintained at normal levels in middle-aged people and that RT did not cause any improvement. Also, RT increases muscle mass, strength, and functional capacity. Despite no additional changes of RT on the antioxidant defenses (catalase, glutathione peroxidase, and reductase) or inflammation, lipid peroxidation was diminished by RT (group x time interaction, p = 0.009), indicating that other antioxidant defenses may be improved after RT. HSR is preserved in middle-aged subjects without metabolic complications. In addition, RT reduces lipid peroxidation and can retard muscle mass and strength loss related to the aging process.

Impact of weight loss with or without exercise on abdominal fat and insulin resistance in obese individuals: a randomised clinical trial.

Evidence supports an important contribution of abdominal obesity and inflammation to the development of insulin resistance (IR) and CVD. Weight loss in obese individuals can reduce inflammation and, consequently, IR, but the role of training remains unclear. The aim of this study was to evaluate the effects of body weight reduction with and without exercise over abdominal fat tissue (primary outcome) and IR. In this randomised clinical trial, forty-eight obese individuals (age 31·8 (SD 6·0) years, BMI 34·8 (SD 2·7) kg/m2) were randomised to either a diet-only group (DI) or a diet and exercise group (DI þ EXE). Treatment was maintained until 5% of the initial body weight was lost. At baseline and upon completion, the following parameters were analysed: biochemical parameters such as glycaemia and insulin for the determination of homeostasis model assessment of insulin resistance (HOMA-IR), high-sensitivity C-reactive protein (hs-CRP) and abdominal computed tomography for the determination of visceral and subcutaneous adipose tissue. A total of thirteen individuals dropped out before completing the weight-loss intervention and did not repeat the tests. In both the DI (n 18) and DI þ EXE (n 17) groups, we observed significant and similar decreases of visceral adipose tissue (difference between means: 7·9 (95% CI 29·5, 25·2) cm2, P»0·36), hs-CRP (difference between means: 20·06 (95% CI 20·19, 0·03) mg/l, P»0·39) and HOMA (difference between means: 20·04 (95% CI 20·17, 0·08), P»0·53). In the present study, 5% weight loss reduced abdominal fat and IR in obese individuals and exercise did not add to the effect of weight loss on the outcome variables.

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.