Marina Yazigi Solis

Rapid weight loss followed by recovery time does not affect judo-related performance

Abstract In this study, we investigated the effects of rapid weight loss followed by a 4-h recovery on judo-related performance. Seven weight-cycler athletes were assigned to a weight loss group (5% body weight reduction by self-selected regime) and seven non-weight-cyclers to a control group (no weight reduction). Body composition, performance, glucose, and lactate were assessed before and after weight reduction (5–7 days apart; control group kept weight stable). The weight loss group had 4 h to re-feed and rehydrate after the weigh-in. Food intake was recorded during the weight loss period and recovery after the weigh-in. Performance was evaluated through a specific judo exercise, followed by a 5-min judo combat and by three bouts of the Wingate test. Both groups significantly improved performance after the weight loss period. No interaction effects were observed. The energy and macronutrient intake of the weight loss group were significantly lower than for the control group. The weight loss group consumed large amounts of food and carbohydrate during the 4-h recovery period. No changes were observed in lactate concentration, but a significant decrease in glucose during rest was observed in the weight loss group. In conclusion, rapid weight loss did not affect judo-related performance in experienced weight-cyclers when the athletes had 4 h to recover. These results should not be extrapolated to inexperienced weight-cyclers.

An overview of the therapeutic effects of leucine supplementation on skeletal muscle under atrophic conditions

The characterization of the mechanisms underlying skeletal muscle atrophy under different conditions has been a constant focus of research. Among anti-atrophic therapies, amino acid supplementation, particularly with leucine, has received a lot of attention. Supplementation has been shown to have remarkable effects on muscle remodeling through protein turnover modulation. This may then impact physiological parameters related to muscle function, and even quality of life. In light of this, leucine supplementation could be a useful therapy for mitigating the atrophic effects of catabolic conditions. The purpose of this review is to present the major results of human studies evaluating the effects of leucine supplementation on structure and function of skeletal muscle in atrophic conditions such as muscle disuse, sarcopenia, and cancer.

Efeitos terapêuticos do treinamento físico em pacientes com doenças reumatológicas pediátricas

Over the past decades, the role of exercise training in rheumatic diseases has been largely explored. Currently, physical activity is well known to benefit patients with osteoporosis, osteoarthritis, systemic lupus erythematosus, systemic sclerosis, idiopathic inflammatory myopathy, fibromyalgia and rheumatoid arthritis. Therefore, exercise training has been considered a valuable tool for treating rheumatic patients. The therapeutic effects of exercise training have also been investigated in pediatric rheumatic diseases. Collectively, studies have revealed the therapeutic potential of exercise in juvenile idiopathic arthritis, juvenile systemic lupus erythematosus, juvenile dermatomyositis, juvenile fibromyalgia and other causes of chronic pain. The aim of this review is to familiarize the pediatric rheumatologist with the exercise science field; discuss the potential benefits of exercise training in pediatric rheumatic diseases, emphasize both research and clinical perspectives of this promising field; and propose practical models of pre-participation examinations and contraindications to exercise.

Liposuction Induces a Compensatory Increase of Visceral Fat Which Is Effectively Counteracted by Physical Activity: A Randomized Trial

CONTEXT Liposuction is suggested to result in long-term body fat regain that could lead to increased cardiometabolic risk. We hypothesized that physical activity could prevent this effect. OBJECTIVE Our objective was to investigate the effects of liposuction on body fat distribution and cardiometabolic risk factors in women who were either exercise trained or not after surgery. DESIGN, SETTING, AND PARTICIPANTS Thirty-six healthy normal-weight women participated in this 6-month randomized controlled trial at the University of Sao Paulo, Sao Paulo, Brazil. INTERVENTIONS Patients underwent a small-volume abdominal liposuction. Two months after surgery, the subjects were randomly allocated into two groups: trained (TR, n = 18, 4-month exercise program) and nontrained (NT, n = 18). MAIN OUTCOME MEASURES Body fat distribution (assessed by computed tomography) was assessed before the intervention (PRE) and 2 months (POST2), and 6 months (POST6) after surgery. Secondary outcome measures included body composition, metabolic parameters and dietary intake, assessed at PRE, POST2, and POST6, and total energy expenditure, physical capacity, and sc adipocyte size and lipid metabolism-related gene expression, assessed at PRE and POST6. RESULTS Liposuction was effective in reducing sc abdominal fat (PRE vs. POST2, P = 0.0001). Despite the sustained sc abdominal fat decrement at POST6 (P = 0.0001), the NT group showed a significant 10% increase in visceral fat from PRE to POST6 (P = 0.04; effect size = -0.72) and decreased energy expenditure (P = 0.01; effect size = 0.95) when compared with TR. Dietary intake, adipocyte size, and gene expression were unchanged over time. CONCLUSION Abdominal liposuction does not induce regrowth of fat, but it does trigger a compensatory increase of visceral fat, which is effectively counteracted by physical activity.

Effect of rapid weight loss on performance in combat sport male athletes: does adaptation to chronic weight cycling play a role?

Background Studies failing to show a negative effect of rapid weight loss (RWL) on performance have been conducted in athletes who have been cycling weight for years. It has been suggested that chronic weight cycling could lead combat athletes to become resistant to the stresses associated with weight loss. To investigate the effects of RWL up to 5% of body mass on high-intensity intermittent performance in weight cyclers (WC) and non-weight cyclers (non-WC). Methods Eighteen male combat athletes (WC: n=10; non-WC: n=8) reduced up to 5% of their body mass in 5 days. Body composition, high-intensity performance and plasma lactate were assessed preweight loss and postweight loss. Athletes had 4 h to re-feed and rehydrate following the weigh-in. Food intake was recorded during the weight loss and the recovery periods. Results Athletes significantly decreased body mass, lean body mass (most likely due to fluid loss) and fat mass following weight loss. No significant changes in performance were found from preweight loss to postweight loss in both groups. Plasma lactate was significantly elevated after exercise in both groups, but no differences were found between groups and in response to RWL. For all these variables no differences were observed between groups. Athletes from both groups ingested high amounts of energy and carbohydrates during the recovery period after the weigh-in. Conclusions Chronic weight cycling does not protect athletes from the negative impact of RWL on performance. The time to recover after weigh-in and the patterns of food and fluid ingestion during this period is likely to play the major role in restoring performance to baseline levels.

Brain creatine depletion in vegetarians? A cross-sectional 1 H-magnetic resonance spectroscopy ( 1 H-MRS) study

The present cross-sectional study aimed to examine the influence of diet on brain creatine (Cr) content by comparing vegetarians with omnivores. Brain Cr content in the posterior cingulate cortex was assessed by proton magnetic resonance spectroscopy (¹H-MRS). Dietary Cr intake was assessed by 3 d food recalls. Vegetarians had lower dietary Cr intake than omnivores (0.03 (SD 0.01) v. 1.34 (SD 0.62) g/d, respectively; P=0.005). However, vegetarians and omnivores had comparable brain total Cr content (5.999 (SD 0.811) v. 5.917 (SD 0.665) IU, respectively; P=0.77). In conclusion, dietary Cr did not influence brain Cr content in healthy individuals, suggesting that in normal conditions brain is dependent on its own Cr synthesis.

Anthropometric, physiological, performance, and nutritional profile of the Brazil National Canoe Polo Team

Abstract The purpose of this study was to determine the physiological, anthropometric, performance, and nutritional characteristics of the Brazil Canoe Polo National Team. Ten male canoe polo athletes (age 26.7 ± 4.1 years) performed a battery of tests including assessments of anthropometric parameters, upper-body anaerobic power (Wingate), muscular strength, aerobic power, and nutritional profile. In addition, we characterized heart rate and plasma lactate responses and the temporal pattern of the effort/recovery during a simulated canoe polo match. The main results are as follows: body fat, 12.3 ± 4.0%; upper-body peak and mean power, 6.8 ± 0.5 and 4.7 ± 0.4 W · kg−1, respectively; 1-RM bench press, 99.1 ± 11.7 kg; peak oxygen uptake, 44.3 ± 5.8 mL · kg−1 · min−1; total energy intake, 42.8 ± 8.6 kcal · kg−1; protein, carbohydrate, and fat intakes, 1.9 ± 0.1, 5.0 ± 1.5, and 1.7 ± 0.4 g · kg−1, respectively; mean heart rate, 146 ± 11 beats · min−1; plasma lactate, 5.7 ± 3.8 mmol · L−1 at half-time and 4.6 ± 2.2 mmol · L−1 at the end of the match; effort time (relative to total match time), 93.1 ± 3.0%; number of sprints, 9.6 ± 4.4. The results of this study will assist coaches, trainers, and nutritionists in developing more adequate training programmes and dietary interventions for canoe polo athletes.

Efficacy and safety of creatine supplementation in childhood-onset systemic lupus erythematosus: a randomized, double-blind, placebo-controlled, crossover trial

Introduction Creatine supplementation has emerged as a promising non-pharmacological therapeutic strategy to counteract muscle dysfunction and low lean mass in a variety of conditions, including in pediatric and rheumatic diseases. The objective of this study was to examine the efficacy and safety of creatine supplementation in childhood systemic lupus erythematosus (C-SLE). Methods C-SLE patients with mild disease activity (n = 15) received placebo or creatine supplementation in a randomized fashion using a crossover, double-blind, repeated-measures design. The participants were assessed at baseline and after 12 weeks in each arm, interspersed by an eight-week washout period. The primary outcomes were muscle function, as assessed by a battery of tests including one-maximum repetition (1-RM) tests, the timed-up-and-go test, the timed-stands test, and the handgrip test. Secondary outcomes included body composition, biochemical markers of bone remodeling, aerobic conditioning, quality of life, and physical capacity. Possible differences in dietary intake were assessed by three 24-hour dietary recalls. Muscle phosphorylcreatine content was measured through phosphorus magnetic resonance spectroscopy (31 P-MRS). The safety of the intervention was assessed by laboratory parameters, and kidney function was measured by 51Cr-EDTA clearance. Additionally, self-reported adverse events were recorded throughout the trial. Results Intramuscular phosphorylcreatine content was not significantly different between creatine and placebo before or after the intervention (creatine-Pre: 20.5 ± 2.6, Post: 20.4 ± 4.1, placebo-Pre: 19.8 ± 2.0; Post: 20.2 ± 3.2 mmol/kg wet muscle; p = 0.70 for interaction between conditions). In addition, probably as a consequence of the lack of change in intramuscular phosphorylcreatine content, there were no significant changes between placebo and creatine for any muscle function and aerobic conditioning parameters, lean mass, fat mass, bone mass, and quality of life scores (p > 0.05). The 51Cr-EDTA clearance was not altered by creatine supplementation and no side effects were noticed. Conclusion A 12-week creatine supplementation protocol at 0.1 g/kg/d is well tolerated and free of adverse effects but did not affect intramuscular phosphorylcreatine, muscle function, free-fat mass or quality of life in non-active C-SLE patients. Trial registration Clinicaltrials.gov number: NCT01217320.

Efficacy and safety of creatine supplementation in juvenile dermatomyositis: A randomized, double‐blind, placebo‐controlled crossover trial

Introduction: It has been suggested that creatine supplementation is safe and effective for treating idiopathic inflammatory myopathies, but no pediatric study has been conducted to date. The objective of this study was to examine the efficacy and safety of creatine supplementation in juvenile dermatomyositis (JDM) patients. Methods: In this study, JDM patients received placebo or creatine supplementation (0.1 g/kg/day) in a randomized, crossover, double‐blind design. Subjects were assessed at baseline and after 12 weeks. The primary outcome was muscle function. Secondary outcomes included body composition, aerobic conditioning, health‐related quality of life, and muscle phosphocreatine (PCr) content. Safety was assessed by laboratory parameters and kidney function measurements. Results: Creatine supplementation did not affect muscle function, intramuscular PCr content, or any other secondary outcome. Kidney function was not affected, and no side effects were reported. Conclusions: Twelve weeks of creatine supplementation in JDM patients were well‐tolerated and free of adverse effects, but treatment did not affect muscle function, intramuscular PCr, or any other parameter. Muscle Nerve 53: 58–66, 2016

Can creatine supplementation form carcinogenic heterocyclic amines in humans

There is a long‐standing concern that creatine supplementation could be associated with cancer, possibly by facilitating the formation of carcinogenic heterocyclic amines (HCAs). This study provides compelling evidence that both low and high doses of creatine supplementation, given either acutely or chronically, does not cause a significant increase in HCA formation. HCAs detection was unrelated to creatine supplementation. Diet was likely to be the main factor responsible for HCAs formation after either placebo (n = 6) or creatine supplementation (n = 3). These results directly challenge the recently suggested biological plausibility for the association between creatine use and risk of testicular germ cell cancer.