Does Sodium-bicarbonate Ingestion Improve Simulated Judo Performance?

International Journal of Sport Nutrition and Exercise Metabolism. Apr, 2007  |  Pubmed ID: 17507744

The aim of the present study was to investigate whether preexercise sodium-bicarbonate ingestion improves judo-related performance. The study used 2 different protocols to evaluate performance: 3 bouts of a specific judo test (n = 9) and 4 bouts of the Wingate test for upper limbs (n = 14). In both protocols athletes ingested 0.3 g/kg of sodium bicarbonate or placebo 2 h before the tests. Blood samples were collected to determine lactate level, and levels of perceived exertion were measured throughout the trials. The study used a double-blind, counterbalanced, crossover design. Ingestion of sodium bicarbonate improved performance in Bouts 2 and 3 of Protocol 1 (P < 0.05), mean power in Bouts 3 and 4 of Protocol 2 (P < 0.05), and peak power in Bout 4 of Protocol 2 (P < 0.05). Ingestion of bicarbonate increased lactate concentration in Protocol 1 (P < 0.05) but not in Protocol 2. Ratings of perceived exertion did not differ between treatments. In conclusion, sodium bicarbonate improves judo-related performance and increases blood lactate concentration but has no effect on perceived exertion.

Effects of Creatine Supplementation on Renal Function: a Randomized, Double-blind, Placebo-controlled Clinical Trial

European Journal of Applied Physiology. May, 2008  |  Pubmed ID: 18188581

Creatine (CR) supplementation is commonly used by athletes. However, its effects on renal function remain controversial. The aim of this study was to evaluate the effects of creatine supplementation on renal function in healthy sedentary males (18-35 years old) submitted to exercise training. A randomized, double-blind, placebo-controlled trial was performed. Subjects (n = 18) were randomly allocated to receive treatment with either creatine (CR) ( approximately 10 g day(-1) over 3 months) or placebo (PL) (dextrose). All subjects undertook moderate intensity aerobic training, in three 40-min sessions per week, during 3 months. Serum creatinine, serum and urinary sodium and potassium were determined at baseline and at the end of the study. Cystatin C was assessed prior to training (PRE), after 4 (POST 4) and 12 weeks (POST 12). Cystatin C levels (mg L(-1)) (PRE CR: 0.82 +/- 0.09; PL: 0.88 +/- 0.07 vs. POST 12 CR: 0.71 +/- 0.06; PL: 0.75 +/- 0.09, P = 0.0001) were decreased over time, suggesting an increase in glomerular filtration rate. Serum creatinine decreased with training in PL but was unchanged with training in CR. No significant differences were observed within or between groups in other parameters investigated. The decrease in cystatin C indicates that high-dose creatine supplementation over 3 months does not provoke any renal dysfunction in healthy males undergoing aerobic training. In addition, the results suggest that moderate aerobic training per se may improve renal function.

Under-reporting of Energy Intake is More Prevalent in a Healthy Dietary Pattern Cluster

The British Journal of Nutrition. Nov, 2008  |  Pubmed ID: 18377688

The aim of the present study was to determine whether under-reporting rates vary between dietary pattern clusters. Subjects were sixty-five Brazilian women. During 3 weeks, anthropometric data were collected, total energy expenditure (TEE) was determined by the doubly labelled water method and diet was measured. Energy intake (EI) and the daily frequency of consumption per 1000 kJ of twenty-two food groups were obtained from a FFQ. These frequencies were entered into a cluster analysis procedure in order to obtain dietary patterns. Under-reporters were defined as those who did not lose more than 1 kg of body weight during the study and presented EI:TEE less than 0.82. Three dietary pattern clusters were identified and named according to their most recurrent food groups: sweet foods (SW), starchy foods (ST) and healthy (H). Subjects from the healthy cluster had the lowest mean EI:TEE (SW = 0.86, ST = 0.71 and H = 0.58; P = 0.003) and EI - TEE (SW = - 0.49 MJ, ST = - 3.20 MJ and H = - 5.08 MJ; P = 0.008). The proportion of under-reporters was 45.2 (95 % CI 35.5, 55.0) % in the SW cluster; 58.3 (95 % CI 48.6, 68.0) % in the ST cluster and 70.0 (95 % CI 61.0, 79) % in the H cluster (P = 0.34). Thus, in Brazilian women, under-reporting of EI is not uniformly distributed among dietary pattern clusters and tends to be more severe among subjects from the healthy cluster. This cluster is more consistent with both dietary guidelines and with what lay individuals usually consider 'healthy eating'.

Does Creatine Supplementation Improve the Plasma Lipid Profile in Healthy Male Subjects Undergoing Aerobic Training?

Journal of the International Society of Sports Nutrition. 2008  |  Pubmed ID: 18831767

We aimed to investigate the effects of creatine (Cr) supplementation on the plasma lipid profile in sedentary male subjects undergoing aerobic training.

Underreporting of Energy Intake in Brazilian Women Varies According to Dietary Assessment: a Cross-sectional Study Using Doubly Labeled Water

Journal of the American Dietetic Association. Dec, 2008  |  Pubmed ID: 19027406

Underreporting of energy intake is prevalent in food surveys, but there is controversy about which dietary assessment method provides greater underreporting rates. Our objective is to compare validity of self-reported energy intake obtained by three dietary assessment methods with total energy expenditure (TEE) obtained by doubly labeled water (DLW) among Brazilian women.

The Possible Role of Physical Exercise on the Treatment of Idiopathic Inflammatory Myopathies

Autoimmunity Reviews. Mar, 2009  |  Pubmed ID: 19041955

Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of diseases that share some symptoms such as muscular weakness and inflammation of skeletal muscle. Complete recovery of muscle function with pharmacological treatment does not always occur, suggesting that physical inability is a great concern for these patients. In this context, it has been speculated that physical exercise could result in functional benefits to patients with IIM, leading to an improvement in quality of life. In fact, recent studies of polymyositis (PM) and dermatomyositis (DM) support the notion that exercise training improves or at least stabilizes muscle strength and functional ability without inducing disease flares. Importantly, these benefits were observed not only during the chronic phase, but also in the course of active disease. This positive effect was found to be long term, as demonstrated by a six-month significant improvement in exercise capacity and strength. Together, these findings indicate that a well controlled exercise program can be recommended for patients with DM and PM. The optimal exercise modality training and the underlying mechanism for this encouraging response remain to be determined in future studies.

Physiological, Performance, and Nutritional Profile of the Brazilian Olympic Wushu (kung-fu) Team

Journal of Strength and Conditioning Research / National Strength & Conditioning Association. Jan, 2009  |  Pubmed ID: 19077742

The purpose of the present study was to determine physiological, nutritional, and performance profiles of elite Olympic Wushu (kung-fu) athletes. Ten men and four women elite athletes took part in the study. They completed the following tests: body composition, nutritional assessment, upper-body Wingate Test, vertical jump, lumbar isometric strength, and flexibility. Blood lactate was determined at rest and after the Wingate Test. Blood lactate was also determined during a training session (combat and Taolu training). We found low body fat (men: 9.5 +/- 6.3%; women: 18.0 +/- 4.8%), high flexibility (sit-and-reach-men: 45.5 +/- 6.1 cm; women: 44.0 +/- 6.3 cm), high leg power (vertical jump-men: 37.7 +/- 8.4 cm; women: 32.3 +/- 1.1 cm), high lumbar isometric strength (men: 159 +/- 13 cm; women: 94 +/- 6 cm), moderate arm mean and peak power (Wingate Test-men: 4.1 +/- 0.4 and 5.8 +/- 0.5 Wxkg, respectively; women: 2.5 +/- 0.3 and 3.4 +/- 0.3 W.kg, respectively), and elevated blood lactate after the Wingate Test (men: 10.8 +/- 2.0 mmolxL; women: 10.2 +/- 2.0 mmolxL) and during training (combat: 12.0 +/- 1.8 mmolxL; Taolu: 7.7 +/- 3.3 mmolxL). Men athletes consume a high-fat, low-carbohydrate diet, whereas women consume a moderate, high-carbohydrate diet. Energy consumption was markedly variable. In conclusion, Olympic Wushu seems to be a highly anaerobic-dependent combat sport. Low body fat, high flexibility, leg anaerobic power, isometric strength, and moderately high arm anaerobic power seem to be important for successful competitive performance.

The Role of Beta-alanine Supplementation on Muscle Carnosine and Exercise Performance

Medicine and Science in Sports and Exercise. Dec, 2009  |  Pubmed ID: 19997023

In this narrative review we present and discuss the current knowledge available on carnosine and beta-alanine metabolism, as well as the effects of beta-alanine supplementation on exercise performance. Intramuscular acidosis has been attributed to be one of the main causes of fatigue during intense exercise. Carnosine has been shown to play a significant role in muscle pH regulation. Carnosine is synthesized in skeletal muscle from the amino acids L-histidine and beta-alanine. The rate-limiting factor of carnosine synthesis is beta-alanine availability. Supplementation with beta-alanine has been shown to increase muscle carnosine content and therefore total muscle buffer capacity, with the potential to elicit improvements in physical performance during high-intensity exercise. Studies on beta-alanine supplementation and exercise performance have demonstrated improvements in performance during multiple bouts of high-intensity exercise and in single bouts of exercise lasting more than 60 s. Similarly, beta-alanine supplementation has been shown to delay the onset of neuromuscular fatigue. While beta-alanine does not improve maximal strength or VO2max, some aspects of endurance performance, such as anaerobic threshold and time to exhaustion, can be enhanced. Symptoms of paresthesia may be observed if a single dose higher than 800 mg is ingested. The symptoms, however, are transient and related to the increase in plasma concentration. They can be prevented by using controlled release capsules and smaller dosing strategies. No important side effect was related to the use of this amino acid so far. In conclusion, beta-alanine supplementation seems to be a safe nutritional strategy capable of improving high-intensity anaerobic performance.

Rapid Weight Loss Followed by Recovery Time Does Not Affect Judo-related Performance

Journal of Sports Sciences. Jan, 2010  |  Pubmed ID: 20035492

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.

Effect of Short-term High-dose Creatine Supplementation on Measured GFR in a Young Man with a Single Kidney

American Journal of Kidney Diseases : the Official Journal of the National Kidney Foundation. Mar, 2010  |  Pubmed ID: 20060630

It currently is unknown whether creatine supplementation is safe for people with or at risk of kidney disease. We report on the short-term effects of creatine supplementation on kidney function in a young man with a single kidney and mildly decreased glomerular filtration rate (GFR). A 20-year-old man who had undergone unilateral nephrectomy and presented with mildly decreased GFR without kidney damage underwent a trial with 35 days of creatine supplementation (20 g/d for 5 days followed by 5 g/d for the next 30 days) and had his kidney function monitored. After the intervention, (51)Cr-EDTA clearance (pre, 81.6 mL/min/1.73 m(2); post, 82.0 mL/min/1.73 m(2)), proteinuria (protein excretion: pre, 130 mg/d; post, 120 mg/d), and electrolyte levels were unchanged. Albuminuria, serum urea level, and estimated creatinine clearance were decreased (pre, 4.6 mg/d; post, 2.9 mg/d; pre, 37 mg/d; post, 28 mg/dL; and pre, 88 mL/min/1.73 m(2); post, 71 mL/min/1.73 m(2), respectively), whereas serum creatinine level was slightly increased (pre, 1.03 mg/dL; post, 1.27 mg/dL), falsely suggesting kidney function impairment. This prospective report suggests that short-term creatine supplementation may not affect kidney function in an individual with a single kidney, mild decreased GFR, and ingesting a high-protein diet (ie, 2.8 g/kg/d). This finding has great relevance considering that creatine-induced kidney disease has been a growing concern, even for healthy people.

Creatine Supplementation Spares Muscle Glycogen During High Intensity Intermittent Exercise in Rats

Journal of the International Society of Sports Nutrition. 2010  |  Pubmed ID: 20205834

The effects of creatine (CR) supplementation on glycogen content are still debatable. Thus, due to the current lack of clarity, we investigated the effects of CR supplementation on muscle glycogen content after high intensity intermittent exercise in rats.

Evidence for Prescribing Exercise As Treatment in Pediatric Rheumatic Diseases

Autoimmunity Reviews. Jun, 2010  |  Pubmed ID: 20388559

There has been an increasing recognition of adverse short-, mid-, or long-term effects associated with the treatment as well as the disease itself that impair the health-related quality of life and functional capacity of children and adolescents with rheumatic diseases. Interestingly, cumulative evidence has suggested that exercise training may benefit patients with juvenile idiopathic arthritis, juvenile systemic lupus erythematosus, juvenile dermatomyositis and juvenile fibromyalgia, attenuating several clinical symptoms related to physical disability. Remarkably, recent evidence also suggests that exercise may have direct effects on the pathogenesis of autoimmune diseases by attenuating chronic low-grade systemic inflammation. It is also important to emphasize that no exercise-related adverse effects have been reported. This short review provides the evidence for physical training as a treatment of pediatric rheumatic diseases, introducing a novel concept that exercise is a treatment for these populations.

Role of Beta-alanine Supplementation on Muscle Carnosine and Exercise Performance

Medicine and Science in Sports and Exercise. Jun, 2010  |  Pubmed ID: 20479615

In this narrative review, we present and discuss the current knowledge available on carnosine and beta-alanine metabolism as well as the effects of beta-alanine supplementation on exercise performance. Intramuscular acidosis has been attributed to be one of the main causes of fatigue during intense exercise. Carnosine has been shown to play a significant role in muscle pH regulation. Carnosine is synthesized in skeletal muscle from the amino acids l-histidine and beta-alanine. The rate-limiting factor of carnosine synthesis is beta-alanine availability. Supplementation with beta-alanine has been shown to increase muscle carnosine content and therefore total muscle buffer capacity, with the potential to elicit improvements in physical performance during high-intensity exercise. Studies on beta-alanine supplementation and exercise performance have demonstrated improvements in performance during multiple bouts of high-intensity exercise and in single bouts of exercise lasting more than 60 s. Similarly, beta-alanine supplementation has been shown to delay the onset of neuromuscular fatigue. Although beta-alanine does not improve maximal strength or VO2max, some aspects of endurance performance, such as anaerobic threshold and time to exhaustion, can be enhanced. Symptoms of paresthesia may be observed if a single dose higher than 800 mg is ingested. The symptoms, however, are transient and related to the increase in plasma concentration. They can be prevented by using controlled release capsules and smaller dosing strategies. No important side effect was related to the use of this amino acid so far. In conclusion, beta-alanine supplementation seems to be a safe nutritional strategy capable of improving high-intensity anaerobic performance.

Low and Moderate, Rather Than High Intensity Strength Exercise Induces Benefit Regarding Plasma Lipid Profile

Diabetology & Metabolic Syndrome. 2010  |  Pubmed ID: 20492685

The effects of chronic aerobic exercise upon lipid profile has been previously demonstrated, but few studies showed this effect under resistance exercise conditions.

Exploring the Therapeutic Role of Creatine Supplementation

Amino Acids. Jan, 2010  |  Pubmed ID: 19253023

Creatine (Cr) plays a central role in energy provision through a reaction catalyzed by phosphorylcreatine kinase. Furthermore, this amine enhances both gene expression and satellite cell activation involved in hypertrophic response. Recent findings have indicated that Cr supplementation has a therapeutic role in several diseases characterized by atrophic conditions, weakness, and metabolic disturbances (i.e., in the muscle, bone, lung, and brain). Accordingly, there has been an evidence indicating that Cr supplementation is capable of attenuating the degenerative state in some muscle disorders (i.e., Duchenne and inflammatory myopathies), central nervous diseases (i.e., Parkinson's, Huntington's, and Alzheimer's), and bone and metabolic disturbances (i.e., osteoporosis and type II diabetes). In light of this, Cr supplementation could be used as a therapeutic tool for the elderly. The aim of this review is to summarize the main studies conducted in this field and to highlight the scientific and clinical perspectives of this promising therapeutic supplement.

Resistance Training with Vascular Occlusion in Inclusion Body Myositis: a Case Study

Medicine and Science in Sports and Exercise. Feb, 2010  |  Pubmed ID: 19927034

Inclusion body myositis (IBM) is a rare idiopathic inflammatory myopathy that produces remarkable muscle weakness. Resistance training with vascular occlusion has been shown to improve muscle strength and cross-sectional area in other muscle wasting conditions.

Prevalence, Magnitude, and Methods of Rapid Weight Loss Among Judo Competitors

Medicine and Science in Sports and Exercise. Mar, 2010  |  Pubmed ID: 19952804

To identify the prevalence, magnitude, and methods of rapid weight loss among judo competitors.

Responsiveness to Exercise Training in Juvenile Dermatomyositis: a Twin Case Study

BMC Musculoskeletal Disorders. 2010  |  Pubmed ID: 21106107

Patients with juvenile dermatomyositis (JDM) often present strong exercise intolerance and muscle weakness. However, the role of exercise training in this disease has not been investigated.

Efficacy and Safety of Concurrent Training in Systemic Sclerosis

Journal of Strength and Conditioning Research / National Strength & Conditioning Association. May, 2011  |  Pubmed ID: 21116202

The optimal training model for patients with systemic sclerosis (SSc) is unknown. In this study, we aimed to investigate the effects of a 12-week combined resistance and aerobic training program (concurrent training) in SSc patients. Eleven patients with no evidence of pulmonary involvement were recruited for the exercise program. Lower and upper limb dynamic strengths (assessed by 1 repetition maximum [1RM] of a leg press and bench press, respectively), isometric strength (assessed by back pull and handgrip tests), balance and mobility (assessed by the timed up-and-go test), muscle function (assessed by the timed-stands test), Rodnan score, digital ulcers, Rayland's phenomenon, and blood markers of muscle inflammation (creatine kinase and aldolase) were assessed at baseline and after the 12-week program. Exercise training significantly enhanced the 1RM leg press (41%) and 1RM bench press (13%) values and back pull (24%) and handgrip strength (11%). Muscle function was also improved (15%), but balance and mobility were not significantly changed. The time-to-exhaustion was increased (46.5%, p = 0.0004), the heart rate at rest condition was significantly reduced, and the workload and time of exercise at ventilatory thresholds and peak of exercise were increased. However, maximal and submaximal &OV0312;o2 were unaltered (p > 0.05). The Rodnan score was unchanged, and muscle enzymes remained within normal levels. No change was observed in digital ulcers and Raynaud's phenomenon. This is the first study to demonstrate that a 12-week concurrent training program is safe and substantially improves muscle strength, function, and aerobic capacity in SSc patients.

Beneficial Effect of Creatine Supplementation in Knee Osteoarthritis

Medicine and Science in Sports and Exercise. Aug, 2011  |  Pubmed ID: 21311365

The aim of this study was to investigate the efficacy of creatine (CR) supplementation combined with strengthening exercises in knee osteoarthritis (OA).

The Effect of Carbohydrate Mouth Rinse on Maximal Strength and Strength Endurance

European Journal of Applied Physiology. Sep, 2011  |  Pubmed ID: 21336838

It has been previously reported that carbohydrate (CHO) mouth rinse can improve exercise performance. The proposed mechanism involves increased activation of brain regions believed to be responsible for reward/motivation and motor control. Since strength-related performance is affected by central drive to the muscles, it seems reasonable to hypothesize that the positive CNS response to oral CHO sensing may counteract the inhibitory input from the muscle afferent pathways minimizing the drop in the central drive. The purpose of the current study was to test if CHO mouth rinse affects maximum strength and strength endurance performance. Twelve recreationally strength-trained healthy males (age 24.08 ± 2.99 years; height 178.09 ± 6.70 cm; weight 78.67 ± 8.17 kg) took part in the study. All of the tests were performed in the morning, after an 8 h overnight fasting. Subjects were submitted to a maximum strength test (1-RM) and a strength endurance test (six sets until failure at 70% of 1-RM), in separate days under three different experimental conditions (CHO mouth rinse, placebo-PLA mouth rinse and control-CON) in a randomized crossover design. The CHO mouth rinse (25 ml) occurred before every attempt in the 1-RM test, and before every set in the endurance strength test. Blood glucose and lactate were measured immediately before and 5 min post-tests. There were no significant differences in 1-RM between experimental conditions (CHO 101 ± 7.2 kg; PLA 101 ± 7.4 kg; CON 101 ± 7.2 kg; p = 0.98). Furthermore, there were no significance between trial differences in the number of repetitions performed in each set (p = 0.99) or the total exercise volume (number of repetitions × load lifted [kg]) (p = 0.98). A main effect for time (p < 0.0001) in blood lactate concentration was observed in both tests (1-RM and strength endurance). Blood glucose concentration did not differ between conditions. In conclusion, CHO mouth rinse does not affect maximum strength or strength endurance performance.

Effects of Creatine Supplementation on Muscle Wasting and Glucose Homeostasis in Rats Treated with Dexamethasone

Amino Acids. Mar, 2011  |  Pubmed ID: 21373767

We aimed to investigate the possible role of creatine (CR) supplementation in counteracting dexamethasone-induced muscle wasting and insulin resistance in rats. Also, we examined whether CR intake would modulate molecular pathways involved in muscle remodeling and insulin signaling. Animals were randomly divided into four groups: (1) dexamethasone (DEX); (2) control pair-fed (CON-PF); (3) dexamethasone plus CR (DEX-CR); and (4) CR pair-fed (CR-PF). Dexamethasone (5 mg/kg/day) and CR (5 g/kg/day) were given via drinking water for 7 days. Plantaris and extensor digitorum longus (EDL) muscles were removed for analysis. Plantaris and EDL muscle mass were significantly reduced in the DEX-CR and DEX groups when compared with the CON-PF and CR-PF groups (P < 0.05). Dexamethasone significantly decreased phospho-Ser(473)-Akt protein levels compared to the CON-PF group (P < 0.05) and CR supplementation aggravated this response (P < 0.001). Serum glucose was significantly increased in the DEX group when compared with the CON-PF group (DEX 7.8 ± 0.6 vs. CON-PF 5.2 ± 0.5 mmol/l; P < 0.05). CR supplementation significantly exacerbated hyperglycemia in the dexamethasone-treated animals (DEX-CR 15.1 ± 2.4 mmol/l; P < 0.05 vs. others). Dexamethasone reduced GLUT-4 translocation when compared with the CON-PF and CR-PF (P < 0.05) groups and this response was aggravated by CR supplementation (P < 0.05 vs. others). In conclusion, supplementation with CR resulted in increased insulin resistance and did not attenuate muscle wasting in rats treated with dexamethasone. Given the contrast with the results of human studies that have shown benefits of CR supplementation on muscle atrophy and insulin sensitivity, we suggest caution when extrapolating this animal data to human subjects.

Effect of Creatine Supplementation on Measured Glomerular Filtration Rate in Postmenopausal Women

Applied Physiology, Nutrition, and Metabolism = Physiologie Appliquée, Nutrition Et Métabolisme. Jun, 2011  |  Pubmed ID: 21574777

We aimed to investigate whether creatine supplementation affects the measured glomerular filtration rate in postmenopausal women (age, 58 ± 3 years). Subjects were randomly assigned to receive either creatine (20 g·day(-1) for 1 week and 5 g·day(-1) thereafter) or a placebo. Kidney function was assessed at baseline and after 12 weeks. [(51)Cr]EDTA clearance remained unchanged (CR-PRE: 86.16 ± 14.36 mL·min(-1) per 1.73 m(2), POST: 87.25 ± 17.60 mL·min(-1) per 1.73 m(2); PL-PRE: 85.15 ± 8.54 mL·min(-1) per 1.73 m(2), POST: 87.18 ± 9.64 mL·min(-1) per 1.73 m(2); p = 0.81). Thus, we concluded that creatine supplementation does not affect glomerular filtration rate in postmenopausal women.

Exercise in a Child with Systemic Lupus Erythematosus and Antiphospholipid Syndrome

Medicine and Science in Sports and Exercise. Dec, 2011  |  Pubmed ID: 21606873

Exercise training has emerged as a potential therapeutic strategy to counteract the decline in physical function and aerobic capacity in pediatric rheumatic disease.

Creatine but Not Betaine Supplementation Increases Muscle Phosphorylcreatine Content and Strength Performance

Amino Acids. Jul, 2011  |  Pubmed ID: 21744011

We aimed to investigate the role of betaine supplementation on muscle phosphorylcreatine (PCr) content and strength performance in untrained subjects. Additionally, we compared the ergogenic and physiological responses to betaine versus creatine supplementation. Finally, we also tested the possible additive effects of creatine and betaine supplementation. This was a double-blind, randomized, placebo-controlled study. Subjects were assigned to receive betaine (BET; 2 g/day), creatine (CR; 20 g/day), betaine plus creatine (BET + CR; 2 + 20 g/day, respectively) or placebo (PL). At baseline and after 10 days of supplementation, we assessed muscle strength and power, muscle PCr content, and body composition. The CR and BET + CR groups presented greater increase in muscle PCr content than PL (p = 0.004 and p = 0.006, respectively). PCr content was comparable between BET versus PL (p = 0.78) and CR versus BET + CR (p = 0.99). CR and BET + CR presented greater muscle power output than PL in the squat exercise following supplementation (p = 0.003 and p = 0.041, respectively). Similarly, bench press average power was significantly greater for the CR-supplemented groups. CR and BET + CR groups also showed significant pre- to post-test increase in 1-RM squat and bench press (CR: p = 0.027 and p < 0.0001; BET + CR: p = 0.03 and p < 0.0001 for upper- and lower-body assessments, respectively) No significant differences for 1-RM strength and power were observed between BET versus PL and CR versus BET + CR. Body composition did not differ between the groups. In conclusion, we reported that betaine supplementation does not augment muscle PCr content. Furthermore, we showed that betaine supplementation combined or not with creatine supplementation does not affect strength and power performance in untrained subjects.

Strength Capacity in Young Patients Who Are Receiving Maintenance Therapy for Acute Lymphoblastic Leukemia: a Case-control Study

Clinics (São Paulo, Brazil). 2011  |  Pubmed ID: 21876987

Therapeutic Effects of Exercise Training in Patients with Pediatric Rheumatic Diseases

Revista Brasileira De Reumatologia. Nov, 2011  |  Pubmed ID: 21953000

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.

Creatine Supplementation Does Not Augment Muscle Carnosine Content in Type 2 Diabetic Patients

Applied Physiology, Nutrition, and Metabolism = Physiologie Appliquée, Nutrition Et Métabolisme. Oct, 2011  |  Pubmed ID: 21999299

We examined whether creatine supplementation affects muscle carnosine content in type 2 diabetic patients. Subjects were randomly assigned to receive either creatine (5 g·day(-1)) or placebo in a double-blind fashion. At baseline and after 12 weeks, carnosine content was evaluated in gastrocnemius and soleus muscles by using a 1H-MRS technique. No changes were found in gastrocnemius (p = 0.81) and soleus (p = 0.85). We concluded that creatine supplementation does not augment muscle carnosine content in type 2 diabetic patients.

Familiarisation with Lower Limb Strength Testing in Middle-aged Women with Osteoarthritis of the Knee

Physiotherapy. Dec, 2011  |  Pubmed ID: 22051593

Cardiac Autonomic Impairment and Chronotropic Incompetence in Fibromyalgia

Arthritis Research & Therapy. Nov, 2011  |  Pubmed ID: 22098761

ABSTRACT: INTRODUCTION: We aimed to gather knowledge on the cardiac autonomic modulation in patients with fibromyalgia (FM) in response to exercise and to investigate whether this population suffers from chronotropic incompetence (CI). METHODS: Fourteen women with FM (age: 46 ± 3 years; body mass index (BMI): 26.6 ± 1.4 kg/m2) and 14 gender-, BMI- (25.4 ± 1.3 kg/m2), and age-matched (age: 41 ± 4 years) healthy individuals (CTRL) took part in this cross-sectional study. A treadmill cardiorespiratory test was performed and heart-rate (HR) response during exercise was evaluated by the chronotropic reserve. HR recovery (deltaHRR) was defined as the difference between HR at peak exercise and at both first (deltaHRR1) and second (deltaHRR2) minutes after the exercise test. RESULTS: FM patients presented lower maximal oxygen consumption (VO2 max) when compared with healthy subjects (22 ± 1 versus CTRL: 32 ± 2 mL/kg/minute, respectively; P < 0.001). Additionally, FM patients presented lower chronotropic reserve (72.5 ± 5 versus CTRL: 106.1 ± 6, P < 0.001), deltaHRR1 (24.5 ± 3 versus CTRL: 32.6 ± 2, P = 0.059) and deltaHRR2 (34.3 ± 4 versus CTRL: 50.8 ± 3, P = 0.002) than their healthy peers. The prevalence of CI was 57.1% among patients with FM. CONCLUSIONS: Patients with FM who undertook a graded exercise test may present CI and delayed HR recovery, both being indicative of cardiac autonomic impairment and higher risk of cardiovascular events and mortality.

In Sickness and in Health: the Widespread Application of Creatine Supplementation

Amino Acids. Nov, 2011  |  Pubmed ID: 22101980

There is an extensive and still growing body of the literature supporting the efficacy of creatine (Cr) supplementation. In sports, creatine has been recognized as the most effective nutritional supplement in enhancing exercise tolerance, muscle strength and lean body mass. From a clinical perspective, the application of Cr supplementation is indeed exciting. Evidences of benefits from this supplement have been reported in a broad range of diseases, including myopathies, neurodegenerative disorders, cancer, rheumatic diseases, and type 2 diabetes. In addition, after hundreds of published studies and millions of exposures creatine supplementation maintains an excellent safety profile. Thus, we contend that the widespread application of this supplement may benefit athletes, elderly people and various patient populations. In this narrative review, we aimed to summarize both the ergogenic and therapeutic effects of Cr supplementation. Furthermore, we reviewed the impact of Cr supplementation on kidney function.

Reduced Muscle Carnosine Content in Type 2, but Not in Type 1 Diabetic Patients

Amino Acids. Nov, 2011  |  Pubmed ID: 22120670

Carnosine is present in high concentrations in skeletal muscle where it contributes to acid buffering and functions also as a natural protector against oxidative and carbonyl stress. Animal studies have shown an anti-diabetic effect of carnosine supplementation. High carnosinase activity, the carnosine degrading enzyme in serum, is a risk factor for diabetic complications in humans. The aim of the present study was to compare the muscle carnosine concentration in diabetic subjects to the level in non-diabetics. Type 1 and 2 diabetic patients and matched healthy controls (total n = 58) were included in the study. Muscle carnosine content was evaluated by proton magnetic resonance spectroscopy (3 Tesla) in soleus and gastrocnemius. Significantly lower carnosine content (-45%) in gastrocnemius muscle, but not in soleus, was shown in type 2 diabetic patients compared with controls. No differences were observed in type 1 diabetic patients. Type II diabetic patients display a reduced muscular carnosine content. A reduction in muscle carnosine concentration may be partially associated with defective mechanisms against oxidative, glycative and carbonyl stress in muscle.

Beta-alanine (Carnosyn™) Supplementation in Elderly Subjects (60-80 Years): Effects on Muscle Carnosine Content and Physical Capacity

Amino Acids. Dec, 2011  |  Pubmed ID: 22143432

The aim of this study was to investigate the effects of beta-alanine supplementation on exercise capacity and the muscle carnosine content in elderly subjects. Eighteen healthy elderly subjects (60-80 years, 10 female and 4 male) were randomly assigned to receive either beta-alanine (BA, n = 12) or placebo (PL, n = 6) for 12 weeks. The BA group received 3.2 g of beta-alanine per day (2 × 800 mg sustained-release Carnosyn™ tablets, given 2 times per day). The PL group received 2 × (2 × 800 mg) of a matched placebo. At baseline (PRE) and after 12 weeks (POST-12) of supplementation, assessments were made of the muscle carnosine content, anaerobic exercise capacity, muscle function, quality of life, physical activity and food intake. A significant increase in the muscle carnosine content of the gastrocnemius muscle was shown in the BA group (+85.4%) when compared with the PL group (+7.2%) (p = 0.004; ES: 1.21). The time-to-exhaustion in the constant-load submaximal test (i.e., TLIM) was significantly improved (p = 0.05; ES: 1.71) in the BA group (+36.5%) versus the PL group (+8.6%). Similarly, time-to-exhaustion in the incremental test was also significantly increased (p = 0.04; ES 1.03) following beta-alanine supplementation (+12.2%) when compared with placebo (+0.1%). Significant positive correlations were also shown between the relative change in the muscle carnosine content and the relative change in the time-to-exhaustion in the TLIM test (r = 0.62; p = 0.01) and in the incremental test (r = 0.48; p = 0.02). In summary, the current data indicate for the first time, that beta-alanine supplementation is effective in increasing the muscle carnosine content in healthy elderly subjects, with subsequent improvement in their exercise capacity.

Creatine in Type 2 Diabetes: a Randomized, Double-blind, Placebo-controlled Trial

Medicine and Science in Sports and Exercise. May, 2011  |  Pubmed ID: 20881878

Creatine supplementation improves glucose tolerance in healthy subjects.

Creatine Supplementation Does Not Impair Kidney Function in Type 2 Diabetic Patients: a Randomized, Double-blind, Placebo-controlled, Clinical Trial

European Journal of Applied Physiology. May, 2011  |  Pubmed ID: 20976468

Creatine supplementation may have a therapeutic role in diabetes, but it is uncertain whether this supplement is safe for kidney function. The aim of this study was to investigate the effects of creatine supplementation on kidney function in type 2 diabetic patients. A randomized, double-blind, placebo-controlled trial was performed. The patients were randomly allocated to receive either creatine or placebo for 12 weeks. All the patients underwent exercise training throughout the trial. Subjects were assessed at baseline and after the intervention. Blood samples and 24-h urine samples were obtained for kidney function assessments. Additionally, (51)Cr-EDTA clearance was performed. To ensure the compliance with creatine intake, we also assessed muscle phosphorylcreatine content. The creatine group presented higher muscle phosphorylcreatine content when compared to placebo group (CR Pre 44 ± 10, Post 70 ± 18 mmol/kg/wt; PL Pre 52 ± 13, Post 46 ± 13 mmol/kg/wt; p = 0.03; estimated difference between means 23.6; 95% confidence interval 1.42-45.8). No significant differences were observed for (51)Cr-EDTA clearance (CR Pre 90.4 ± 16.9, Post 96.1 ± 15.0 mL/min/1.73 m(2); PL Pre 97.9 ± 21.6, Post 96.4 ± 26.8 mL/min/1.73 m(2); p = 0.58; estimated difference between means -0.3; 95% confidence interval -24.9 to 24.2). Creatinine clearance, serum and urinary urea, electrolytes, proteinuria, and albuminuria were unchanged. CR supplementation does not affect kidney function in type 2 diabetic patients, opening a window of opportunities to explore its promising therapeutic role in this population. ClinicalTrials.gov registration number: NCT00992043.

Anthropometric, Physiological, Performance, and Nutritional Profile of the Brazil National Canoe Polo Team

Journal of Sports Sciences. 2012  |  Pubmed ID: 22168392

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.