Acid–Base Balance, Blood Gases Saturation, and Technical Tactical Skills in Kickboxing Bouts According to K1 Rules

Background: Acid–base balance (ABB) is a major component of homeostasis, which is determined by the efficient functioning of many organs, including the lungs, kidneys, and liver, and the proper water and electrolyte exchange between these components. The efforts made during competitions by combat sports athletes such as kickboxers require a very good anaerobic capacity, which, as research has shown, can be improved by administering sodium bicarbonate. Combat sports are also characterized by an open task structure, which means that cognitive and executive functions must be maintained at an appropriate level during a fight. The aim of our study was to analyze the changes in ABB in capillary blood, measuring levels of H+, pCO2, pO2, HCO3−, BE and total molar CO2 concentration (TCO2), which were recorded 3 and 20 min after a three-round kickboxing bout, and the level of technical and tactical skills presented during the fight. Methods: The study involved 14 kickboxers with the highest skill level (champion level). Statistical comparison of mentioned variables recorded prior to and after a bout was done with the use of Friedman’s ANOVA. Results: 3 min after a bout, H+ and pO2 were higher by 41% and 11.9%, respectively, while pCO2, HCO3−, BE and TO2 were lower by 14.5%, 39.4%, 45.4% and 34.4%, respectively. Furthermore, 20 min after the bout all variables tended to normalization and they did not differ significantly compared to the baseline values. Scores in activeness of the attack significantly correlated (r = 0.64) with pre–post changes in TCO2. Conclusions: The disturbances in ABB and changes in blood oxygen and carbon dioxide saturation observed immediately after a bout indicate that anaerobic metabolism plays a large part in kickboxing fights. Anaerobic training should be included in strength and conditioning programs for kickboxers to prepare the athletes for the physiological requirements of sports combat.

Downplaying the role of water in the rheological changes of conducting polymers by using water-in-salt electrolytes

Volumetric changes associated with solvent/electrolyte exchange in electronic conducting polymers (ECPs) play an important role in the mechanical stability of the polymers, as these changes are a critical factor in...

Impact of Diffusion, Ultrafiltration, and Posture on Total Body Electrical Resistance in Patients on Hemodialysis

Background Monitoring of hydration in patients on hemodialysis (HD) by currently available bioelectrical impedance analysis (BIA) methods is hampered by limited accuracy. This may be caused by changes in total body electrical resistance (TBER) that are induced by processes other than ultrafiltration (UF). To identify these sources of error we examined the impact of UF, diffusion, and postural change (PC), separately. Methods Extracellular TBER (TBERe) was measured by bioimpedance spectroscopy every 30 min in 23 patients on HD, for 2 hours during diffusion-only (DO), followed by 2 hours UF-only (UFO). The impact of PC from upright to semi-recumbent position was assessed by a 2-hour TBERe measurement on the day after HD. Results TBERe increased by 23.5 ± 12.4 Ω (P < 0.001) during DO and by 40.0 ± 16.2 Ω (P < 0.001) during UFO. PC, evaluated on a separate day, was associated with an increase in TBERe of 27.6 ± 26.0 Ω (P < 0.001). TBERe changes during DO were mainly attributed to PC and to a lesser extent to electrolyte exchange. Extrapolation of the data to a conventional 4-hour HD session indicates that about 32% of the total increase in TBERe is not related to UF. Conclusions A significant part of the increase in TBER during HD is not related to UF but can be attributed to other processes such as the effects of PC and diffusion-related electrolyte exchange. These factors have to be taken into account when TBER-guided UF is considered.

DYNAMICS OF THE CONTENT OF WATER-ELECTROLYTE EXCHANGE IN PATIENTS WITH TRAUMATIC BRAIN INJURY DURING PERIOPERATIVE PERIOD

Objective. To study the dynamics of the content of sodium, potassium, chloride, magnesium, calcium, phosphorus and iron of the serum and determine the possibility of their use as prognostic criteria for the outcome of treatment of patients with traumatic brain injury (TBI).Material and methods. Two groups were formed of 76 patients with TBI. Group 1 - 46 patients with a favorable outcome of treatment, group 2-30 patients with an adverse outcome. Serum electrolytes between groups were compared during the first 10 days after craniotomy at 7 stages of the study.Results. Between groups of patients differences in the content of K+ at the initial stage of the study (1-2 hours before surgery); Na+ and Cl- at stage 2 of the study (11 (6; 17) hours after surgery) and iron at 5-7 stages of the study (at the 5th, 7th and 10th day after the operation) were revealed. At all stages of the study when comparing groups of patients by the content of phosphorus, magnesium and calcium in the blood serum no significant differences were revealed.Conclusion. The best predictor of an adverse TBI outcome was serum iron on the 5th day after surgery – 2.5 (1.9; 5.2) mmol/l, AUC=0.73, Se=68.8, Sp=60%; on the 7th day after the operation - 3.7 (2.6; 4.3) mmol/l, AUC=0.73,Se=64.7%, Sp=72%; on the 10th day after the operation, 3.6 (1.9; 5.7) μmol/l, AUC=0.69, Se=73.7%, Sp=52.4%.

A quantitative analysis of electrolyte exchange in the salivary duct

A healthy salivary gland secretes saliva in two stages. First, acinar cells generate primary saliva, a plasma-like, isotonic fluid high in Na+ and Cl−. In the second stage, the ducts exchange Na+ and Cl− for K+ and HCO3−, producing a hypotonic final saliva with no apparent loss in volume. We have developed a tool that aims to understand how the ducts achieve this electrolyte exchange while maintaining the same volume. This tool is part of a larger multiscale model of the salivary gland and can be used at the duct or gland level to investigate the effects of genetic and chemical alterations. In this study, we construct a radially symmetric mathematical model of the mouse salivary gland duct, representing the lumen, the cell, and the interstitium. For a given flow and primary saliva composition, we predict the potential differences and the luminal and cytosolic concentrations along a duct. Our model accounts well for experimental data obtained in wild-type animals as well as knockouts and chemical inhibitors. Additionally, the luminal membrane potential of the duct cells is predicted to be very depolarized compared with acinar cells. We investigate the effects of an electrogenic vs. electroneutral anion exchanger in the luminal membrane on concentration and the potential difference across the luminal membrane as well as how impairing the cystic fibrosis transmembrane conductance regulator channel affects other ion transporting mechanisms. Our model suggests the electrogenicity of the anion exchanger has little effect in the submandibular duct.