[Dietary management of the Parkinson's patient: a necessity at every stage of the digestive system]. / Prise en charge diététique du patient parkinsonien : une nécessité à chaque étape du système digestif.

Nutrition is a recurrent theme in the care of patients with Parkinson's disease. The aim of this article is to focus on the nutritional problems encountered in this pathology, and to clarify the role of the dietician in its management.

[The realities of hunger and thirst at the end of life]. / Les réalités de la faim et la soif en fin de vie.

Questions about nutrition and hydration are common in the context of the end of life. By end of life, we mean the terminal palliative phase, a particular period of organic fragility. These questions pose difficulties, insofar as the act of eating and drinking as a vital act has a symbolic, cultural and social dimension. They must be clarified with family members or even caregivers who are not familiar with these types of care.

[Evaluation of the results and feasibility of vibration, diuresis and inversion therapy in the treatment of upper urinary tract stones]. / Évaluation des résultats et de la faisabilité de la posturothérapie (hydratation, inversion, vibration) dans le traitement des calculs des voies urinaires supérieures.

OBJECTIVES: To evaluate the feasibility, efficiency, and predictive factors of therapeutic success of Vibration, Diuresis and Inversion (VDI) therapy for the removal of upper urinary tract stones. METHODS: It is a retrospective, single-center study at the CHU - La Conception, Marseille, France including all patients treated with VDI from 2013 to 2018. VDI was indicated for stones <6mm in first-line treatment or for residual fragments <6mm after ureteroscopy, PCNL, microPCNL. The protocol included 4 sessions in outpatient care from 2013 to 2015 then 6 sessions from 2015 to 2018 and a final radiological evaluation. RESULTS: In total, 109 patients or 489 sessions are reported: median age was 55 years [14-84], median BMI 25kg/m2 [15-37], average cumulative size of kidney stones 3mm ±4. VDI was performed after flexible ureteroscopy (62%), SWL (20%), percutaneous treatment (9%) or as a first-line treatment (9%). Compliance was 87 %. The median VAS during the session was 0[0-8]. The incidence of post-session renal colic was 4% (all Clavien I). The postoperative fragment-free and microfragment rates were respectively 39% and 21%, i.e. an overall success of 60% for kidney stones, and 43% and 21%, i.e. an overall success of 64% for lower pole kidney stones. CONCLUSION: VDI is a simple, non invasive and well tolerated technique for the elimination of small renal lithiasis after SWL, ureteroscopy, PCNL or as a first-line treatment.

Recomendaciones basadas en la evidencia sobre la nutrición e hidratación en los últimos días de vida / Evidence-based recommendations on nutrition and hydration in the last days of life

Resumen: Introducción: Los cuidados paliativos en México son contemplados como una necesidad en todos los niveles de atención. La nutrición e hidratación en estos enfermos hacia sus últimos días de vida es controversial. Objetivo: Identificar las recomendaciones basadas en la evidencia sobre la nutrición e hidratación en los últimos días de vida. Material y métodos: Se realizó una búsqueda documental sobre la nutrición e hidratación hacia el final de la vida tomando como marco temporal las últimas horas y/o los últimos días de vida del enfermo en el contexto hospitalario. Resultados: Con los criterios de búsqueda seleccionados se identificaron 83 documentos. No se encontraron metaanálisis. Existen dos revisiones sistematizadas de la literatura, un ensayo clínico, cuatro guías de práctica clínica, cuatro reportes de caso y 17 revisiones. Se desglosan los resultados relevantes de lo seleccionado. Conclusiones: Se identifica que existen controversias de fondo sobre la alimentación al final de la vida. Sobre la hidratación existe cierto consenso. Es indispensable contar con un nutriólogo dentro de los servicios de cuidados paliativos de la Nación.

Abstract: Introduction: Palliative care in Mexico is considered a necessity at all levels of care. Nutrition and hydration in these patients towards the last days of life is controversial. Objective: To identify evidence-based recommendations on nutrition and hydration in the last days of life. Material and methods: A documentary search on nutrition and hydration towards the end of life was carried out taking as a time frame the last hours and/or the last days of life of the patient in the hospital context. Results: With the selected search criteria, 83 documents were identified. No meta-analyses were found. There are two systematized literature reviews, one clinical trial, four clinical practice guidelines, four case reports and 17 reviews. The relevant results of the selected documents are broken down. Conclusions: It is identified that there are fundamental controversies about feeding at the end of life. On hydration there is some consensus. It is essential to have a nutritionist within the palliative care services of the Nation.

Provision of instructions to drink ad libitum or according to thirst sensation: impact during 120 km of cycling in the heat in men.

The terms drinking to thirst and ad libitum drinking are used interchangeably, but should they? We investigated the differences in how athletes consumed fluids during exercise when instructed to drink according to thirst or ad libitum. Using a randomized, crossover, and counterbalanced design, 10 males (27 ± 4 y) cycled 120 km (48 ± 4% of peak power, 33 °C, 40% relative humidity) on 2 occasions, while drinking water according to thirst or ad libitum. Participants covered the cycling trials in 222 ± 11 min (p = 0.29). Although the body mass loss at the end of exercise and total volume of water consumed were similar between trials, thirst perception before each sip and the volume consumed per sip were significantly higher with thirst than ad libitum drinking, whereas the total number of sips was significantly lower with thirst than ad libitum drinking. Perceived exertion, rectal temperature, and heart rate were all significantly higher with thirst than ad libitum drinking, but the difference was trivial. In conclusion, thirst and ad libitum drinking are associated with different drinking patterns, but equally maintain fluid balance during prolonged exercise. The terms drinking to thirst and ad libitum drinking can be used interchangeably to guide fluid intake during prolonged exercise. Novelty: Both strategies are associated with different patterns of fluid ingestion during prolonged exercise, but are equally effective in maintaining fluid balance. Perceived exertion, rectal temperature, and heart rate are regulated dissimilarly by thirst and ad libitum drinking, but the difference is trivial.

Valoración del impacto del confinamiento por SARS-CoV-2 sobre la composición corporal de una población de futbolistas de élite / Assessment of the impact of confinement by SARS-CoV-2 on the body composition of elite soccer players

RESUMEN: El confinamiento por pandemia por SARS-CoV-2 ha agravado la condición física y nutricional de los deportistas de élite, modificando la rutina de los entrenamientos. La bioimpedancia (BIA) estudia la composición corporal y es utilizada para valorar la evolución de las intervenciones médicas, deportivas y nutricionales. El objetivo del estudio fue observar si una intervención nutricional y una prescripción de actividad física específicas pudieron atenuar los cambios hídricos, de composición corporal, y ángulo de fase (PhA) tras el confinamiento por la pandemia SARS-CoV-2 en una población de futbolistas de élite. En un grupo de 22 futbolistas profesionales (Serie A, Calcio, Italia) se evaluó la BIA antes (febrero 2020) y después (mayo 2020) del confinamiento por la pandemia SARS-CoV-2. Durante el periodo de confinamiento se aplicó una intervención nutricional y prescripción de actividad física específicas. Las medidas de los participantes se realizaron de forma protocolizada, usando material antropométrico y un impedanciómetro multifrecuencia, octopolar y segmental de la marca Tanita modelo MC-780MA. Se aplicó la prueba t de Student para muestras relacionadas. No se observaron diferencias significativas antes y después del periodo de intervención, en el grado de hidratación y composición corporal (masa muscular y masa grasa). Por el contrario, se evidenció un cambio significativo en el PhA. Estos datos nos permiten poder tener una referencia de que intervenciones nutricionales y de actividad física pueden minimizar o disminuir el impacto de un confinamiento en la composición corporal. No obstante, este tipo intervención no fue capaz de atenuar los efectos del confinamiento sobre el PhA, considerado un indicador de la salud celular. Así mismo, aportamos una gráfica vectorial de referencia, mediante SpecificBIVA, de esta población.

SUMMARY: The confinement due to a SARS-CoV-2 pandemic has aggravated the physical and nutritional condition of elite athletes, modifying their training routine. Bioimpedance (BIA) studies body composition and is used to assess the evolution of medical, sports and nutritional interventions. The objective of the study was to observe if a specific nutritional intervention and prescription of physical activity could attenuate the changes in water, body composition, and phase angle (PhA) after confinement due to the SARS-CoV-2 pandemic in a population of professional soccer players. In a group of (22 professional soccer players (Serie A, Calcio, Italy) the BIA was evaluated before (February 2020) and after (May 2020) the confinement due to the SARS-CoV-2 pandemic. During the confinement period, a specific nutritional intervention and prescription of physical activity was applied. The measurements of the participants were carried out in a standardized way, using anthropometric material and a multifrequency, octopolar and segmental impedance measurer of the "Tanita" brand model MC-780MA. Student's T test was applied for related samples. No significant differences were observed before and after the intervention period, in the degree of hydration and body composition (muscle mass and fat mass). On the contrary, a significant change in PhA was evidenced. These data allow us to hav a reference for nutritional and physical activity interventions that can minimize or reduce the impact of confinement on body composition. However, this type of intervention was not able to attenuate the effects of confinement on PhA, considered an indicator of cellular health. Likewise, we provide a reference vector graph, using Specific BIVA, of this population.

D-chiro-inositol as a treatment in plaque psoriasis: A randomized placebo-controlled clinical trial.

Cyclitols are widely available natural sugars which do not exert toxic effects. Their anti-inflammatory and antioxidant properties may be used in the treatment of psoriasis. The aim of this placebo-controlled, double-blind study was to evaluate the clinical effects of D-chiro-inositol (DCI) in mild plaque psoriasis (46 psoriatic patients and 10 healthy volunteers). Three stable psoriatic plaques were selected for evaluation in every patient. Different samples were applied on each lesion twice a day: vehiculum without an active agent, containing 1% DCI and 0.25% DCI. The lesions were assessed using the PSI, VAS scale, and the objective measurement of hydration, transepidermal water loss (TEWL), elasticity, and thickness (DermaLab Combo) at 0, 3, and 6 weeks. PSI and VAS were improved in all groups without significant statistical differences. 1% DCI sample presented the highest statistically significant increase in the hydration of 50%, but it was still significantly lower than in healthy controls. TEWL increased for 1% DCI, which was a statistically significant difference compared to 0.25% DCI and still higher than in controls. An improvement in elasticity was observed in all lesions-it was statistically significant for 1% DCI. The thickness of the lesion decreased for 1% DCI, but the change was not statistically significant. Subepidermal low-echogenic band showed a decreasing tendency in all groups, but it was not statistically significant. Favorable 1% DCI sample results indicate that it may be used as an adjuvant to the local treatment of psoriasis.

Mild dehydration impaired intermittent sprint performance and thermoregulation in females.

The effects of mild dehydration during ice hockey are well-studied in males but not females. In a randomized, crossover design, 11 female varsity hockey players drank no fluid (1.7% ± 0.3% body mass loss) or water to maintain hydration during simulated-hockey exercise. Core temperature (P < 0.01) and perceived fatigue (P = 0.02) were higher and sprint power lower (P < 0.01) when mildly dehydrated. Thus, mild dehydration may impair hockey performance and thermoregulation while increasing perceived fatigue in females. Novelty Female stop-and-go sport athletes may benefit their in-game sprint performance and thermoregulation by following personalized in-game hydration to prevent becoming mildly dehydrated.

Bias varies for bioimpedance analysis and skinfold technique when stratifying collegiate male athletes' fat-free mass hydration levels.

This study evaluated the accuracy of bioimpedance analysis (BIA)- and skinfold (SF)-based body fat percentage estimates in collegiate athletes with varying fat-free mass (FFM) hydration levels. Subjects were evaluated as a whole (n = 63) and at FFM hydration levels of 64.00%-68.99% (FFM-HydrationL1; n = 37) and 69.00%-74.00% (FFM-HydrationL2; n = 26). Proportional bias was absent in the SF technique when stratifying FFM hydration levels. Contrarily, proportional bias was observed when using BIA for FFM-HydrationL1, but not in FFM-HydrationL2. Novelty Fat-free mass hydration levels impact BIA-based body fat estimates more than skinfold-based body fat.

Bioelectrical impedance analysis does not detect an increase in total body water following isotonic fluid consumption.

PURPOSE: To determine if single-frequency foot-to-foot bioelectrical impedance analysis (BIA) can detect acute changes in total body water (TBW) following consumption of isotonic saline. All participants ate a sodium-free meal at 4 h prior to the data collection visit and had euhydration confirmed using urine specific gravity at the beginning of the experimental visit. Subjects drank 466 mL of isotonic saline (Na+ 140 mmol·L-1) following baseline measures. Blood sampling and BIA were performed at baseline and every 30 min for 3 h after saline consumption. Ten healthy participants completed this study. Plasma volume (5%Δ, p < 0.001) and serum sodium concentration (1%Δ, p < 0.001) increased by 60 min and 90 min, respectively. Body mass (p < 0.001) displayed a biphasic response increasing to a peak at 30 min (+0.38Δkg) and then decreasing to its minimum at 180 min (-0.35Δkg). BIA impedance (p = 0.678) was unaffected by the saline administration. BIA-derived TBW (p = 0.039) decreased from baseline starting at 150 min (0.21Δkg). Novelty Athletes and coaches wishing to achieve hyperhydration can do so through the consumption of isotonic fluid. 50 kHz foot-to-foot BIA-derived TBW is inadequate for measuring hyperhydration. Future studies should examine the physiological and performance effects of such a hyperhydration protocol.

Fluid, energy, and nutrient recovery via ad libitum intake of different commercial beverages and food in female athletes.

This study investigated the effect of consuming different commercial beverages with food ad libitum after exercise on fluid, energy, and nutrient recovery in trained females. On 4 separate occasions, 8 females (body mass (BM): 61.8 ± 10.7 kg; maximal oxygen uptake: 46.3 ± 7.5 mL·kg-1·min-1) lost 2.0% ± 0.3% BM cycling at ∼75% maximal oxygen uptake before completing a 4-h recovery period with ad libitum access to 1 of 4 beverages: Water, Powerade (Sports Drink), Up & Go Reduced Sugar (Lower Sugar (LS)-MILK) or Up & Go Energize (Higher Protein (HP)-MILK). Participants also had two 15-min opportunities to access food within the first 2 h of the recovery period. Beverage intake, total water/nutrient intake, and indicators of fluid recovery (BM, urine output, plasma osmolality), gastrointestinal tolerance and palatability were assessed periodically. While total water intake (from food and beverage) (Water: 1918 ± 580 g; Sports Drink: 1809 ± 338 g; LS-MILK: 1458 ± 431 g; HP-MILK: 1523 ± 472 g; p = 0.010) and total urine output (Water: 566 ± 314 g; Sports Drink: 459 ± 290 g; LS-MILK: 220 ± 53 g; HP-MILK: 230 ± 117 g; p = 0.009) differed significantly by beverage, the quantity of ingested water retained was similar across treatments (Water: 1352 ± 462 g; Sports Drink: 1349 ± 407 g; LS-MILK: 1238 ± 400 g; HP-MILK: 1293 ± 453 g; p = 0.691). Total energy intake (from food and beverage) increased in proportion to the energy density of the beverage (Water: 4129 ± 1080 kJ; Sports Drink: 5167 ± 643 kJ; LS-MILK: 6019 ± 1925 kJ; HP-MILK: 7096 ± 2058 kJ; p = 0.014). When consumed voluntarily and with food, different beverages promote similar levels of fluid recovery, but alter energy/nutrient intakes. Providing access to food and understanding the longer-term dietary goals of female athletes are important considerations when recommending a recovery beverage.

[Skin hydration and hydrating products]. / Hydratation cutanée et produits hydratants.

One of the skin's principal functions is to protect the body against its environment by maintaining an effective epidermal barrier, not only against external factors, but also to prevent water loss from the body. Indeed, water homeostasis is vital for the normal physiological functioning of skin. Hydration levels affect not only visible microscopic parameters such as the suppleness and softness of skin, but also molecular parameters, enzyme activities and cellular signalling within the epidermis. The body is continually losing some of its water, but this phenomenon is limited and the optimal hydration gradient in skin is ensured via a set of sophisticated regulatory processes that rely on the functional and dynamic properties of the uppermost level of the skin consisting of the stratum corneum. The present article brings together data recently acquired in the fields of skin hydration and the characterisation of dehydrated or dry skin, whether through study of the regulatory processes involved or as a result of changes in the techniques used for in situ measurement, and thus in optimisation of management.

Preparation and efficacy assessment of malva nut polysaccharide for skin hydrating products.

INTRODUCTION: Scaphium scaphigerum or malva nut has long been served in Chinese medicine. However, the use of this herb in modern health care applications has, to date, been rarely reported. MATERIALS AND METHODS: Maceration of the herb in water afforded malva nut polysaccharide which was standardized. Safety and skin hydrating efficacy of the polysaccharide and products were evaluated in human volunteers. RESULTS: Malva nut polysaccharide (41.71±0.64%) having 36.58±0.51% total sugar content was isolated, with further analysis quantifying ash, carbohydrate, reducing sugar and moisture contents to be 6.05±0.00, 40.06±1.00, 12.20±0.05 and 12.64±0.31%, respectively. The polysaccharide exhibited swelling and hydrating capacities of 0.46±0.01% and 54.46±0.02g/g, with L*, a* and b* of 52.56±0.04, 9.02±0.06 and 18.42±0.03, respectively, and a viscosity of 1263.00±2.00 cps. Accelerated testing indicated the biopolysaccharide to be stable, resulting in no skin irritation in 15 human volunteers. The skin hydrating efficacy as assessed via a randomized single-blind, placebo-controlled study in 24 volunteers highlighted the superior performance of malva nut over the vehicle (moisture retainment for 70min as examined by Corneometer® CM 825). A stable skin moisturizing gel containing malva nut was developed and was shown to exhibit improved performance over benchmark tamarind and algae polysaccharide gels (after 180min observation). CONCLUSION: Malva nut polysaccharide has potential as a key ingredient in skin hydrating products, which should encourage its further development.

Why do team-sport athletes drink fluid in excess when exercising in cool conditions?

This study assessed the potential physiological and perceptual drivers of fluid intake and thirst sensation during intermittent exercise. Ten male rugby players (17 ± 1 years, stature: 179.1 ± 4.2 cm, body mass (BM): 81.9 ± 8.1 kg) participated in six 6-min small-sided games, interspersed with 2 min rest, where fluid intake was ad libitum during rest periods. Pre- and postmeasurements of BM, subjective ratings (thirst, thermal comfort, thermal sensation, mouth dryness), plasma osmolality (POsm), serum sodium concentration (S[Na+]), haematocrit and haemoglobin (to calculate plasma volume change; PV) were taken. Fluid intake was measured during rest periods. BM change was -0.17 ± 0.59% and fluid intake was 0.88 ± 0.38 L. Pre- to post-POsm decreased (-3.1 ± 2.3 mOsm·kg-1; p = 0.002) and S[Na+] remained similar (-0.3 ± 0.7 mmol·L-1, p = 0.193). ΔPV was 5.84 ± 3.65%. Fluid intake displayed a relationship with pre-POsm (r = -0.640, p = 0.046), prethermal comfort (r = 0.651; p = -0.041), ΔS[Na+] (r = 0.816, p = 0.004), and ΔPV (r = 0.740; p = 0.014). ΔThirst sensation displayed a relationship with premouth dryness (r = 0.861, p = 0.006) and Δmouth dryness (r = 0.878, p = 0.004). Yet a weak positive relationship between Δthirst sensation and fluid intake was observed (r = 0.085, p = 0.841). These data observed in an ambient temperature of 13.6 ± 0.9 °C, suggest team-sport athletes drink in excess of fluid homeostasis requirements and thirst sensation in cool conditions; however, this was not influenced by thermal discomfort.

Nighttime feeding likely alters morning metabolism but not exercise performance in female athletes.

The timing of morning endurance competition may limit proper pre-race fueling and resulting performance. A nighttime, pre-sleep nutritional strategy could be an alternative method to target the metabolic and hydrating needs of the early morning athlete without compromising sleep or gastrointestinal comfort during exercise. Therefore, the purpose of this investigation was to examine the acute effects of pre-sleep chocolate milk (CM) ingestion on next-morning running performance, metabolism, and hydration status. Twelve competitive female runners and triathletes (age, 30 ± 7 years; peak oxygen consumption, 53 ± 4 mL·kg(-1)·min(-1)) randomly ingested either pre-sleep CM or non-nutritive placebo (PL) ∼30 min before sleep and 7-9 h before a morning exercise trial. Resting metabolic rate (RMR) was assessed prior to exercise. The exercise trial included a warm-up, three 5-min incremental workloads at 55%, 65%, and 75% peak oxygen consumption, and a 10-km treadmill time trial (TT). Physiological responses were assessed prior, during (incremental and TT), and postexercise. Paired t tests and magnitude-based inferences were used to determine treatment differences. TT performances were not different ("most likely trivial" improvement with CM) between conditions (PL: 52.8 ± 8.4 min vs CM: 52.8 ± 8.0 min). RMR was "likely" increased (4.8%) and total carbohydrate oxidation (g·min(-1)) during exercise was "possibly" or likely increased (18.8%, 10.1%, 9.1% for stage 1-3, respectively) with CM versus PL. There were no consistent changes to hydration indices. In conclusion, pre-sleep CM may alter next-morning resting and exercise metabolism to favor carbohydrate oxidation, but effects did not translate to 10-km running performance improvements.

Elite male Flat jockeys display lower bone density and lower resting metabolic rate than their female counterparts: implications for athlete welfare.

To test the hypothesis that daily weight-making is more problematic to health in male compared with female jockeys, we compared the bone density and resting metabolic rate (RMR) in weight-matched male and female Flat jockeys. RMR (kcal·kg(-1) lean mass) was lower in males compared with females as well as lower bone-density Z scores at the hip and lumbar spine. Data suggest the lifestyle of male jockeys compromise health more severely than females, possibly because of making weight more frequently.

[Urinary tract infections: Economical impact of water intake]. / Infections des voies urinaires : impact économique de la consommation d'eau.

BACKGROUNDS: This study aims to estimate the impact of preventing urinary tract infections (UTI), using a strategy of increased water intake, from the payer's perspective in the French health care system. METHODS: A Markov model enables a comparison of health care costs and outcomes for a virtual cohort of subjects with different levels of daily water intake. The analysis of the budgetary impact was based on a period of 5years. The analysis was based on a 25-year follow-up period to assess the effects of adequate water supply on long-term complications. RESULTS: The authors estimate annual primary incidence of UTI and annual risk of recurrence at 5.3% and 30%, respectively. Risk reduction associated with greater water intake reached 45% and 33% for the general and recurrent populations, respectively. The average total health care cost of a single UTI episode is €1074; for a population of 65 millions, UTI management represents a cost of €3.700 millions for payers. With adequate water intake, the model indicates a potential cost savings of €2.288 millions annually, by preventing 27 million UTI episodes. At the individual level, the potential cost savings is approximately €2915. CONCLUSIONS: Preventing urinary tract infections using a strategy of adequate water intake could lead to significant cost savings for a public health care system. Further studies are needed to assess the effectiveness of such an approach.

[Withdrawal of artificial nutrition and hydration in severe stroke: medical, legal and ethical considerations]. / Aspects médicaux, législatifs et éthiques de l'arrêt de la nutrition et de l'hydratation artificielles dans l'accident vasculaire cérébral grave.

In the majority of cases, severe stroke is accompanied by difficulty in swallowing and an altered state of consciousness requiring artificial nutrition and hydration. Because of their artificial nature, nutrition and hydration are considered by law as treatment rather basic care. Withdrawal of these treatments is dictated by the refusal of unreasonable obstinacy enshrined in law and is justified by the risk of severe disability and very poor quality of life. It is usually the last among other withholding and withdrawal decisions which have already been made during the long course of the disease. Reaching a collegial consensus on a controversial decision such as artificial nutrition and hydration withdrawal is a difficult and complex process. The reluctance for such decisions is mainly due to the symbolic value of food and hydration, to the fear of "dying badly" while suffering from hunger and thirst, and to the difficult distinction between this medical act and euthanasia. The only way to overcome such reluctance is to ensure flawless accompaniment, associating sedation and appropriate comfort care with a clear explanation (with relatives but also caregivers) of the rationale and implications of this type of decision. All teams dealing with this type of situation must have thoroughly thought through the medical, legal and ethical considerations involved in making this difficult decision.

Hyaluronan, a truly "youthful" polysaccharide. Its medical applications.

Hyaluronan (hyaluronic acid, HA) is a ubiquitous linear polysaccharide endowed with some exceptional physicochemical properties such as strong hydration and viscoelasticity that depend on the size of the molecule. It plays a variety of important physiological roles in tissue hydration and mechanical protection, for example in the umbilical cord, skin and most other tissues. Since its large scale preparation and the invention by E.A. Balazs of the preparation of its non-inflammatory fraction (NIF-NaHA), there have been several important medical and cosmetic applications, most notably of viscosurgery for eye operation, intra-articular injections for osteoarthritis and also for wrinkle filling on the face, as well as for drug administration. Its concentration in tissues is decreasing with age, source of loss of function and structure of tissues. The purpose of this review is to present a succinct overview of the essential properties of hyaluronan and its medical and esthetic applications.

Sodium-induced hyperhydration decreases urine output and improves fluid balance compared with glycerol- and water-induced hyperhydration.

Before 2010, which is the year the World Anti-Doping Agency banned its use, glycerol was commonly used by athletes for hyperhydration purposes. Through its effect on osmoreceptors, we believe that sodium could prove a viable alternative to glycerol as a hyperhydrating agent. Therefore, this study compared the effects of sodium-induced hyperhydration (SIH), glycerol-induced hyperhydration (GIH) and water-induced hyperhydration (WIH) on fluid balance responses. Using a randomized, double-blind and counterbalanced protocol, 17 men (21 ± 3 years, 64 ± 6 kg fat-free mass (FFM)) underwent three 3-h hyperhydration protocols during which they ingested, over the first 60-min period, 30 mL/kg FFM of water with (i) an artificial sweetener (WIH); (ii) an artificial sweetener + 7.45 g/L of table salt (SIH); or (iii) an artificial sweetener + 1.4 g glycerol/kg FFM (GIH). Changes in body weight (BW), urine production, fluid retention, hemoglobin, hematocrit, plasma volume, and perceptual variables were monitored throughout the 3-h trials. After 3 h, SIH was associated with significantly (p < 0.05) lower hemoglobin, hematocrit (SIH: 43.1% ± 2.8%; GIH: 44.9% ± 2.4%), and urine production, as well as greater BW, fluid retention (SIH: 1144 ± 294 mL; GIH: 795 ± 337 mL), and plasma volume (SIH: 11.9% ± 12.0%; GIH: 4.0% ± 6.0%) gains, compared with GIH and WIH. No significant differences in heart rate or abdominal discomfort were observed between treatments. In conclusion, our results indicate that SIH is a superior hyperhydrating technique than, and proves to be a worthwhile alternative to, GIH.