Body composition measured by multi-frequency bioelectrical impedance following creatine supplementation.

BACKGROUND: Acute fluid ingestion increases estimated body fat percentage (BF%) measurements by single frequency (SF-BIA) and multi-frequency bioelectrical impedance (MF-BIA). It is unknown if MF-BIA accurately measures total BF% and total body water (TBW) after creatine supplementation, which causes fluid retention, and resultant increases in fat-free mass and TBW. The purpose of this study was to analyze the effect of creatine supplementation on body composition and TBW measured through a popular MF-BIA device (InBody 770). METHODS: Thirteen male and 14 female subjects (18-22 years) completed one week of creatine monohydrate (0.3 g/kg body weight) or maltodextrin. Pre- and post-supplementation body composition measurements included dual-energy X-ray absorptiometry (DEXA), SF-BIA measured by an Omron HBF-306C device, and MF-BIA measured by an InBody 770 device to measure BF%, fat free mass (FFM), and fat mass (FM). Additionally, intracellular water (ICW), extracellular water (ECW), and TBW were estimated by MF- BIA. RESULTS: FFM increased more in the creatine group than the placebo group measured by all body composition modes (1.2 kg, 1.9 kg, and 1.1 kg increase for SF-BIA, MF-BIA, and DEXA respectively, P<0.05). Creatine supplementation resulted in a 2% increase (P<0.05) in TBW measured by MF-BIA (40.4±9.5 to 41.2±9.6 kg). CONCLUSIONS: One week of creatine supplementation increased TBW as detected by the InBody 770 device. Changes in body composition that occurred due to the increase in TBW were detected as an increase in FFM measured by SF-BIA, MF-BIA, and DEXA.

Creatine monohydrate supplementation changes total body water and DXA lean mass estimates in female collegiate dancers.

Collegiate dance is unique because it requires athletic and academic performance; therefore, optimizing physical and mental function is crucial. Research among athletic populations demonstrate improvements in body composition, performance, and cognition following creatine monohydrate (CR) supplementation, yet dancers have not been investigated. The purpose of this study was to determine the effects of CR supplementation on body composition, performance, and cognitive function in female collegiate dancers. Participants were randomized to CR (CR; n = 7; 0.1 g·kg -1·day -1 CM +0.1 g·kg -1·day -1 corn-starch maltodextrin) or placebo (PL; n = 6; 0.2 g·kg -1·day -1 corn-starch maltodextrin) for 42 days. Pre- and post-testing included body composition, total body water (TBW), Depression, Anxiety and Stress Scale, Diet History Questionnaire, the National Institute of Health Toolbox fluid cognition battery and isokinetic strength, vertical jump, medicine ball throw, and Wingate anaerobic power test. CR demonstrated a significant increase in TBW (pre, 32.2 ± 3.5 kg; post, 32.7 ± 3.6 kg; p = 0.024) and lean mass (LM; pre, 39.8 ± 3.6 kg; post, 41.5 ± 4.5 kg; p = 0.020). CR supplementation may be an effective strategy to increase TBW and estimates of LM in female collegiate dancers. Although this may optimize aesthetics, larger samples sizes with resistance training are needed to determine if CR supplementation increases muscle mass and translates to improved performance.

Physiological effects of Therapeutic Body Wraps in healthy volunteers: An observational study.

INTRODUCTION: The clinical management of severe anxiety is challenging. Along with specific medication, several nonpharmacological treatments exist, among which the Therapeutic Body Wraps (TBW). While TBW is clinically known to be efficient, the absence of objective physiological measurements raised some debates about its harmlessness. AIMS: This observational study investigated TBW in healthy volunteers. METHODS: Measurements were done in 26 participants, who experienced TBW, which consisted of tightly wrapping the body in one layer of wet cold sheets and several warm blankets. These were compared to 13 participants, who rested in supine position. RESULTS: Our results showed increase in the trunk skin temperature by the end of TBW similar to rest. Somatosensory perception as assessed with quantitative sensory testing was stable after both TBW and rest. The heart and breath rates decreased both during TBW and rest. It was accompanied by increase in heart rate variability parameters and decrease in salivary cortisol levels. DISCUSSION: Our data indicate anxiolytic effect of TBW in healthy participants. IMPLICATIONS FOR PRACTICE: The TBW is harmless and might be used in patients, who are unable to relax by themselves and/or without anxiolytic medication. Further studies are necessary to investigate physiological response to TBW in clinical population.

Effects of glucosamine and chondroitin sulfate supplementation in addition to resistance exercise training and manual therapy in patients with knee osteoarthritis: A randomized controlled trial.

OBJECTIVE: To determine the added benefits of short-term glucosamine and chondroitin sulfate supplementation in combination with manual therapy and resistance exercise training in the management of knee osteoarthritis. METHODS: A parallel-design, double-blind randomised controlled trial was conducted from January to September 2020 at the Foundation University Institute of Rehabilitation Sciences and Fauji Foundation Hospital, Rawalpindi, Pakistan, and comprised of knee osteoarthritis patients of either gender having radiological evidence of grade III or less on Kellgren classification. The subjects were randomly allocated to active comparator group A and experimental group B. Both the groups received manual therapy and resistance exercise training, while group B additionally received glucosamine and chondroitin sulfate supplementation for 4 weeks. Study outcomes included pain, function, quality of life, range of motion, strength, fall risk, skeletal muscle mass, visceral fat area, body fat, intracellular water ratio, and segmental lean and fat mass. Data was analysed using SPSS 21. RESULTS: Of the 24 subjects, there were 12(50%) in each of the two groups. Each groups had 9(75%) males and 3(25%) females. In terms knee osteoarthritis grade, there was no significant difference between the groups (p=1.00). No significant differences were observed in any of the outcome measures neither at 2 weeks, nor at 4 weeks post-intervention between the groups (p>0.05) except for percentage change in segmental lean mass of the right leg at 2nd week and of the left leg at 4th week (p<0.05). CONCLUSIONS: Manual therapy and resistance exercise training are effective in the management of knee osteoarthritis, however, glucosamine and chondroitin sulfate supplementation for 4 weeks showed no additional benefits. Clinical Trial Number: NCT04654871. https://www.clinicaltrials.gov/ct2/show/NCT04654871.

The clinical application value of the extracellular-water-to-total-body-water ratio obtained by bioelectrical impedance analysis in people with advanced cancer.

OBJECTIVES: Body-composition analysis using bioelectrical impedance analysis is gradually becoming more widely used in clinical practice. The ratio of extracellular water (ECW) to total body water (TBW) is thought to be related to the prognosis of a variety of diseases. However, its performance in people with advanced cancer deserves further discussion. METHODS: A retrospective analysis was performed on 784 people with advanced cancer. Anthropometric indicators, serologic indicators, nutritional status, health-related quality of life, and body composition were analyzed. Participants were grouped into two groups according to ECW/TBW ratio. We used t tests and χ2 tests to analyze differences between the groups. Univariate and multivariate Cox regressions were conducted to analyze the factors influencing overall survival. Logistic regression was used to analyze the related factors of malnutrition, and linear regression for factors of health-related quality of life. RESULTS: Age, body mass index, Patient-Generated Subjective Global Assessment score, Karnofsky Performance Status questionnaire score, skeletal muscle mass index, and fat-free mass index were statistically different between the non-overhydrated and overhydrated groups. Univariate and multivariate Cox regression models showed that an ECW/TBW ≥ 0.40 is a risk factor for poor prognosis in people with advanced cancer (hazard ratio = 1.511; 95% confidence interval, 1.103-2.070; P = 0.010). Subgroup analyses were next conducted according to tumor type, with ECW/TBW ≥ 0.40 emerging as a risk factor for poor prognosis for people with advanced breast cancer and advanced gastric cancer. Logistic regression showed that ECW/TBW ≥ 0.40 is a risk factor for malnutrition in people with advanced cancer (odds ratio = 1.988; 95% confidence interval, 1.049-3.767; P = 0.035). The univariate and multivariate linear regression models showed that the ECW/TBW ratio is an influencing factor for health-related quality of life in the domains of physical functioning, role functioning, and constipation. CONCLUSION: We found that in people with cancer, an ECW/TBW ≥ 0.40 was a risk factor for malnutrition and lower health-related quality of life, and in people with advanced cancer, it was a risk factor for poor prognosis.

Oral Intake of Enzymatically Decomposed AP Collagen Peptides Improves Skin Moisture and Ceramide and Natural Moisturizing Factor Contents in the Stratum Corneum.

The stratum corneum (SC) is the outermost layer of the epidermis and plays an important role in maintaining skin moisture and protecting the skin from the external environment. Ceramide and natural moisturizing factor (NMF) are the major SC components that maintain skin moisture. In this study, we investigated whether the oral intake of enzymatically decomposed AP collagen peptides (APCPs) can improve skin moisture and barrier function by assessing changes in the ceramide and NMF contents in the SC after APCP ingestion with the aim to develop a skin functional food. Fifty participants orally ingested APCP (1000 mg) or placebo for 12 weeks, and then, skin hydration and skin texture were evaluated. SC samples were collected to analyze skin scaling, ceramide, and NMF contents. Participants in the APCP group exhibited improved skin moisture content by 7.33% (p = 0.031) and roughness by -4.09% (p = 0.036) when compared with those in the placebo group. NMF content; the amounts of amino acids (AA), including glycine and proline; and AA derivatives were significantly increased in the APCP group (31.98 µg/mg protein) compared to those in the placebo group (-16.01 µg/mg protein) (p = 0.006). The amounts of total ceramides and ceramide subclasses were significantly higher in the APCP group than in the placebo group (p = 0.014). In conclusion, our results demonstrate that APCP intake improves skin moisture and increase the ceramide and NMF contents in the SC, thereby enhancing the skin barrier function.

Xinshuitong Capsule extract attenuates doxorubicin-induced myocardial edema via regulation of cardiac aquaporins in the chronic heart failure rats.

Doxorubicin (Dox), an effective antineoplastic drug, was limited use for cardiotoxicity. Xinshuitong Capsule (XST), a patented herbal formula, showed desirable beneficial effects in the treatment of chronic heart failure (CHF) patients. However, the drug on Dox-induced cardiotoxicity remains unclear. Ninety male Sprague-Dawley rats were randomized into two groups: 15 rats were selected as the normal group and 75 rats were injected intraperitoneally with Dox to establish CHF rat models, the success ones were randomly divided into five groups: low XST (LXST), medium XST (MXST) or high XST (HXST) (4.9, 9.8, or 19.6 g/kg d) administrated intragastrically twice a day for 4 weeks, with the captopril-treated group and the model group as comparison. The model group showed the cardiac functions generally impaired, and CHF mortality rate higher (47%) than those in the XST-treated groups (averaged 24%, P < 0.05). Compared with XST-treated groups, myocardial remodeling, inflammation and desarcomerization, and higher water content more severe in the cardiac tissue in the model group (P < 0.05), which was associated with higher expressions of mRNA or protein levels of AQP1, 4 and 7. Dox-impaired cardiac functions, cardiac remodeling and myocardial edema could be dose-dependently reverted by XST treatment. XST could inhibit AQP1, 4 and 7 at mRNA levels or at protein levels, which was associated with the attenuation of myocardial edema and cardiac remodeling, decreasing the ventricular stiffness and improving the cardiac functions and rats' survival. AQPs is involved in cardiac edema composed one of the mechanisms of Dox-induced cardiotoxicity, XSTvia inhibition of AQPs relieved the Dox-induced side effects.

Sodium/glucose cotransporter 2 and renoprotection: From the perspective of energy regulation and water conservation.

Sodium/glucose cotransporter 2 (SGLT2) is a renal low-affinity high-capacity sodium/glucose cotransporter expressed in the apical membrane of the early segment of proximal tubules. SGLT2 reabsorbs filtered glucose in the kidney, and its inhibitors represent a new class of oral medications used for type 2 diabetes mellitus, which act by increasing glucose and sodium excretion in urine, thereby reducing blood glucose levels. However, clinical trials showed marked improvement of renal outcomes, even in nondiabetic kidney diseases, although the underlying mechanism of this renoprotective effect is unclear. We showed that long-term excretion of salt by the kidneys, which predisposes to osmotic diuresis and water loss, induces a systemic body response for water conservation. The energy-intensive nature of water conservation leads to a reprioritization of systemic body energy metabolism. According to current data, use of SGLT2 inhibitors may result in similar reprioritization of energy metabolism to prevent dehydration. In this review article, we discuss the beneficial effects of SGLT2 inhibition from the perspective of energy metabolism and water conservation.

Molecular mechanisms of brain water transport.

Our brains consist of 80% water, which is continuously shifted between different compartments and cell types during physiological and pathophysiological processes. Disturbances in brain water homeostasis occur with pathologies such as brain oedema and hydrocephalus, in which fluid accumulation leads to elevated intracranial pressure. Targeted pharmacological treatments do not exist for these conditions owing to our incomplete understanding of the molecular mechanisms governing brain water transport. Historically, the transmembrane movement of brain water was assumed to occur as passive movement of water along the osmotic gradient, greatly accelerated by water channels termed aquaporins. Although aquaporins govern the majority of fluid handling in the kidney, they do not suffice to explain the overall brain water movement: either they are not present in the membranes across which water flows or they appear not to be required for the observed flow of water. Notably, brain fluid can be secreted against an osmotic gradient, suggesting that conventional osmotic water flow may not describe all transmembrane fluid transport in the brain. The cotransport of water is an unconventional molecular mechanism that is introduced in this Review as a missing link to bridge the gap in our understanding of cellular and barrier brain water transport.

Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show?

Supplementing with creatine is very popular amongst athletes and exercising individuals for improving muscle mass, performance and recovery. Accumulating evidence also suggests that creatine supplementation produces a variety of beneficial effects in older and patient populations. Furthermore, evidence-based research shows that creatine supplementation is relatively well tolerated, especially at recommended dosages (i.e. 3-5 g/day or 0.1 g/kg of body mass/day). Although there are over 500 peer-refereed publications involving creatine supplementation, it is somewhat surprising that questions regarding the efficacy and safety of creatine still remain. These include, but are not limited to: 1. Does creatine lead to water retention? 2. Is creatine an anabolic steroid? 3. Does creatine cause kidney damage/renal dysfunction? 4. Does creatine cause hair loss / baldness? 5. Does creatine lead to dehydration and muscle cramping? 6. Is creatine harmful for children and adolescents? 7. Does creatine increase fat mass? 8. Is a creatine 'loading-phase' required? 9. Is creatine beneficial for older adults? 10. Is creatine only useful for resistance / power type activities? 11. Is creatine only effective for males? 12. Are other forms of creatine similar or superior to monohydrate and is creatine stable in solutions/beverages? To answer these questions, an internationally renowned team of research experts was formed to perform an evidence-based scientific evaluation of the literature regarding creatine supplementation.

A New Zealand green-lipped mussel oil-enriched high-fat diet exhibits beneficial effects on body weight and metabolism in mice.

To induce diet-induced obesity (DIO) in rodents, diets high in saturated fat and/or carbohydrates are commonly used. In the laboratory, standardised diets evolved over time without paying particular attention to the effect of fat composition on metabolic alterations. In the present study, customised high-fat diets (HFD) enriched with a combination of lard and different concentrations of New Zealand green-lipped mussel (Perna canaliculus) oil or MSC Hoki (Macruronus novaezelandiae, blue grenadier) liver oil, important sources of n-3 PUFA, in comparison with a solely lard-based diet, were fed to lean and DIO male C57BL/6 mice and their effects on metabolic parameters were monitored. Intriguingly, an isoenergetic HFD containing 63 % of total fat in the form of mussel oil and only 28 % in the form of lard attenuated HFD-induced body weight gain after 1 and 4 weeks, respectively. Consistently, changing a lard-enriched HFD to the mussel oil diet reduced body weight markedly even after mice had been exposed to the former diet for 10 months. The weight-reducing effect of the diet was not caused by altered energy intake or expenditure, but was associated with reduced visceral fat mass. Collectively, these data suggest a novel weight-reducing potential of green-lipped mussel oil.

Galuteolin Inhibited Autophagy for Neuroprotection Against Transient Focal Cerebral Ischemia in Rats.

Galuteolin, a Chinese herbal medicine, purified from Lonicera Japonica. In this study, we aimed to investigate the neuroprotective effect of galuteolin against cerebral ischemia/reperfusion (I/R) injury. We administered galuteolin or galuteolin and rapamycin to rats which had middle cerebral artery occlusion/reperfusion (MCAO/R). A series of characterizations were carried out to monitor the outcomes of galuteolin in I/R rats regarding the infarct volumes, neurological deficits, and brain water, as well as its effect on neuroprotection and autophagy. It was found that galuteolin significantly reduced the infarct volume, brain water content, and the neurological deficits in a dose-dependent manner. Neuron damages were decreased in the hippocampal carotid artery 1 pyramidal layer by galuteolin. The expression levels of neuron-specific enolase (NSE) increased after galuteolin treatment. Galuteolin significantly decreased the expression levels of autophagy-related proteins. In addition, galuteolin decreased rapamycin-related neuron damages and activations of autophagy in I/R rats. Our data suggested that galuteolin can inhibit ischemic brain injuries through the regulation of autophagy-related indicators in I/R.

Safety and Efficacy of Oral Intake of Ceramide-Containing Acetic Acid Bacteria for Improving the Stratum Corneum Hydration: A Randomized, Double-Blind, Placebo-Controlled Study over 12 Weeks.

The barrier function of the skin protects it from external stresses to which it is constantly exposed, such as dryness, ultraviolet rays, and chemicals. Lipids, in particular a type of sphingolipid known as ceramides, play a central role in the barrier function of the skin by preventing dryness. The number of ceramides in the skin is known to decrease with age, which has led to the development of a large number of anti-aging cosmetic products that contain ceramides. Recently, it has become evident that oral intake of ceramides can also improve the quality of the skin. To elucidate the effects of oral ceramide intake on skin moisture content, we conducted a randomized, double-blinded, placebo-controlled parallel comparative study in which males and females between 20 and 60 years of age who were worried about dry skin ingested a food with acetic acid bacteria containing 0.8 mg of dihydroceramide or a placebo for 12 weeks. Concurrently, we investigated the safety of continuous ingestion of the ceramide-containing food over 12 weeks. Oral intake of ceramide over the 12 weeks significantly improved stratum corneum hydration, i.e. the moisture content of the skin, and did not result in harmful effects in any of the participants.

The Association Between Extracellular Water-to-Total Body Water Ratio and Therapeutic Durability for Advanced Lung Cancer.

BACKGROUND/AIM: Extracellular water-to-total body water ratio (ECW/TBW) measured by bioelectrical impedance analysis (BIA) reportedly predicts clinical outcomes of various diseases. The aim of this retrospective study was to examine the association between ECW/TBW and therapeutic durability of chemotherapy and/or immune checkpoint inhibitors in advanced lung cancer. PATIENTS AND METHODS: Patients with advanced lung cancer underwent BIA before chemotherapy and/or treatment with immune checkpoint inhibitors at our hospital between June 2018 and November 2019. RESULTS: Of 75 patients, 18 with ECW/TBW ≥0.4 were assigned to the overhydrated group (OH-G) and 57 patients ECW/TBW <0.4 were assigned to the non-overhydrated group (NOH-G). The median time-to-treatment failure was significantly shorter in the OH-G than in the NOH-G (p=0.003). Multivariate analysis revealed that ECW/TBW ≥0.4 predicted treatment failure [hazard ratio (HR)=2.508, 95% confidence interval (CI)=1.19-5.27; p=0.01]. CONCLUSION: The ECW/TBW may be an objective parameter for predicting therapeutic durability in advanced lung cancer.

Administration of Apple Polyphenol Supplements for Skin Conditions in Healthy Women: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

This clinical study was performed to evaluate the effects of continuous apple polyphenol (AP) administration on facial skin conditions and pigmentation induced by ultraviolet (UV) irradiation in healthy women participants. Participants (n = 65, age 20-39 years) were randomized to receive tablets containing AP (300 or 600 mg/day) or placebo in a double-blinded, placebo-controlled clinical trial. Continuous administration of AP for 12 weeks significantly prevented UV irradiation induced skin pigmentation (erythema value, melanin value, L value), although a dose-dependent relationship was not clearly observed. In contrast, no significant differences were detected between the groups with regard to water content and trans-epidermal water loss. Our study demonstrated that APs and their major active compounds, procyanidins, have several health benefits. Here, we report that continuous administration of AP for 12 weeks alleviated UV irradiation induced skin pigmentation, when compared with placebo, in healthy women.

Effect of an Oral Nutrition Supplement Containing Collagen Peptides on Stratum Corneum Hydration and Skin Elasticity in Hospitalized Older Adults: A Multicenter Open-label Randomized Controlled Study.

OBJECTIVE: The purpose of this randomized open-label study was to investigate the effect of an oral nutrition supplement containing collagen peptides on stratum corneum hydration and skin elasticity. METHODS: The study protocol was registered at the UMIN Clinical Trials Registry (UMIN 000027347). Once-a-day oral administration of a nutrition supplement containing collagen peptides (10.0 g) was instituted in 39 inpatients 65 years or older who were assigned to either the intervention or the control group using a block-randomization design. Stratum corneum hydration and skin elasticity were measured at baseline and at 2, 4, 6, and 8 weeks after the start of the intervention. RESULTS: Mean stratum corneum hydration was significantly increased from 43.7 at baseline to 51.7 at postintervention week 8 in the intervention group (P = .001). Differences in skin elasticity from baseline were significant at postintervention week 6 (P = .026) and week 8 (P = .049). CONCLUSIONS: Oral nutrition supplements containing collagen peptides may reduce skin vulnerability in older adults and thus prevent conditions such as skin tears.

Cell integrity indicators assessed by bioelectrical impedance: A systematic review of studies involving athletes.

INTRODUCTION: Bioelectrical impedance analysis (BIA) has been used to evaluate cellular health and integrity through bioelectrical indicators. In the sporting context, monitoring these indicators can be useful to assess the quality and vitality of cells and body tissues. OBJECTIVE: The aim of this systematic review was to investigate indicators of cellular health and integrity evaluated by BIA in athletes. METHODS: Searches were performed in December 2017 in the Lilacs, Medline, PubMed, Science Direct, Scielo, Scopus, SPORTDiscus, and Web of Science databases, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: The searches retrieved 31 articles (30 involving professional athletes and one involving university athletes). In longitudinal studies (n = 15), the bioelectrical parameters directly associated with cellular health and integrity were extracellular water (ECW), phase angle (PA), BIA vector analysis (BIVA), crude reactance data (Xc), resistance (R), and ECW/BCM ratio. Regarding the findings of cross-sectional studies (n = 16), the investigated parameters (ECW, PA, BIVA, Z, BCM, and ECW/BCM) were directly associated with gender, age, sports performance level, modality, and game position. CONCLUSIONS: In the included studies, the cellular health and integrity indicators were: Z, Xc, R, total water, intracellular water, ECW, PA, BIVA, BCM, and ECW/BCM.

Effect of a mixture of botanicals extracts plus mannitol on hydration and bloating sensation. An open label study in women with high extra cellular water.

The aim of the study is to evaluate the effectiveness of of 4 and 8 week supplementation with highly standardized formula with Fraxinus ornus L., plus Ananas comosus L., concentrated juice, Betula pendula R., Equisetum arvense L., Urtica dioica L. and Pilosella officinarum L. Vail dry extract, on the state of hydration and bloating sensation in subjects with high and moderate extra cellular water (ECW). 19 women (mean age 35 yr and Body Mass Index 22.82 kg\m2) with Extra Cellular Water over 45%completed the study and their data were analysed at baseline, at 30 and 60 days. Bio-impedance, SF36 and anthropometric parameters were assessed. The ECW decreased of -1.97% (at 30 days) and -2.30% (60 days) (p < 0.01). Also fat mass decreased of -1.58% (at 30 days) and -2.21% (60 days) (p = 0.057). An improvement of free fat mass was assessed (p < 0.05) but not on bloating sensation questionnaire at 60 days (p = 0.422).

Usefulness of raw bioelectrical impedance parameters in tracking fluid shifts in judo athletes.

Bioelectrical impedance (BI) has been widely used but clarification about the behaviour of raw BI measurements under specific athletic conditions is required. Thus, we determined the usefulness of raw BI measures in tracking body fluids changes during the preparation period prior to competition in elite Judo athletes. At baseline (weight stability), 27 male athletes were evaluated (23.2 ± 2.8y) and again 1-3 days before competition (∼1-2 months apart). Athletes were free to gain/lost weight based upon specific competition needs. Using dilution techniques (deuterium and bromide), total-body water (TBW) and extracellular water were estimated, and intracellular water calculated as TBW minus extracellular water. Body fluid distribution was determined as Extra-to-/Intracellular water (E/I). Fat and fat-free mass (FFM) was assessed by dual-energy x-ray absorptiometry. Resistance, reactance, and phase angle (PhA) were obtained from bioelectrical impedance spectroscopy (50-kHz frequency). No differences in raw BI measures were observed between athletes that lost (N = 17) or gain weight (N = 10), except for fat, FFM, extracellular water, and EI (p < 0.05). After adjusting for FFM and height, resistance explained TBW (ß = -0.047, p = 0.002) and extracelular water (ß = -0.025, p = 0.001). Reactance explained ECW (ß = -0.098, p = 0.004) and EI (ß = -0.004, p = 0.006), while PhA predicted TBW (ß = 1.609, p = 0.047), ICW (ß = 1.899, p = 0.001) and EI (ß = -0.056, p = 0.001). Regardless of body composition changes, athletes who increase reactance and resistance reduced extracellular water and body fluids while those who raised PhA increased intracellular water. Judo athletes who reduced weight, decreased FFM but cellular health was not compromised, as PhA remained stable and, consequently, cell hydration.

Sauna, sweat and science II - do we sweat what we drink?

Inspired by a previous 'Sauna, sweat and science' study [Zech et al. Isot Environ Health Stud. 2015;51(3):439-447] and out of curiosity and enthusiasm for stable isotope and sauna research we aimed at answering the question 'do we sweat (isotopically) what we drink'? We, therefore, pulse-labelled five test persons in a sauna experiment with beverages that were 2H-enriched at about +25,600 ‰. Sweat samples were collected during six sauna rounds and the hydrogen isotope composition δ2Hsweat was determined using an isotope ratio mass spectrometer. Before pulse labelling, δ2Hsweat - reflecting by approximation body water - ranged from -32 to -22 ‰. This is ∼35 ‰ enriched compared to usual mid-European drinking water and can be explained with hydrogen-bearing food as well as with the respiratory loss of 2H-depleted vapour. The absence of a clearly detectable 2H pulse in sweat after pulse labelling and δ2Hsweat results of ≤+250 ‰ due to a fast 2H equilibration with body water are moreover a clearly negative answer to our research question also in a short-term consideration. Given that the recovery of the tracer based on an isotope mass balance calculation is clearly below 100 %, we finally answer the question 'where did the rest of the tracer go?'