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BACKGROUND: There are non-invasive methods of correcting genu valgum (GV), but to date, there is no method to evaluate mechanotherapeutic intervention that does not restrict child's natural movements while the process is on-going so that timely decisions could be made on effectiveness of intervention. The aim of study was to develop and assess the comfortability of garments with elastic straps and pressure applicator (GESPA) and the reliability and user-friendliness of "GVcorrect" app, which aims to catch the elastic straps' pressure level (mN). METHODS: 6 children (5-7 y) with intermalleolar distance ≥5 cm wore GESPA daily for 3 months. Anthropometrical and goniometrical measurements were done according to standard technique; tone and biomechanical parameters of skeletal muscles determined with MyotonPRO; feedback about GESPA and "GVcorrect" collected via questionnaire. RESULTS: Based on feedback from children and parents, new, more comfortable and user-friendly GESPA were designed; several updates were made to "GVcorrect" app; new goals were set for the next phase of the study. CONCLUSIONS: GESPA and the "GVcorrect" app serve their purpose, but there are still a number of important limitations that need to be removed before the product can be marketed. The study continues with product development until a medical device certificate is obtained.

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PURPOSE: Dietary supplements inducing alkalosis have been shown to be ergogenic during intense endurance exercise in temperate environments, but there is lack of data regarding the efficacy of these substances in the heat. This study aimed to investigate the effect of sodium citrate (CIT) ingestion on 5,000-m running performance in a warm environment. METHODS: Sixteen non-heat-acclimated endurance-trained males (age 25.8 ± 4.4 years, VO2peak 56.9 ± 4.7 mL kg min) completed two 5,000-m self-paced treadmill runs with preceding CIT or placebo (wheat flour; PLC) ingestion in a double-blind, randomized, crossover manner in a climatic chamber (air temperature 32 °C, relative humidity 50 %). RESULTS: CIT ingestion (500 mg kg(-1) body mass) compared to PLC induced increases in water retention, body mass and plasma volume (P < 0.05). Pre- and post-exercise blood HCO3 (-) concentration, base excess and pH were higher (P < 0.001) in CIT compared to PLC trial. Rectal temperature, body heat storage, heat storage rate, heart rate and 5,000-m running time (18.92 ± 2.05 min in CIT, 19.11 ± 2.38 min in PLC; 66 % likelihood of benefit, d = -0.09) were similar (P > 0.05) in the two trials. Post-exercise blood lactate concentration was higher (P < 0.001) in CIT (11.05 ± 3.22 mmol L(-1)) compared to PLC trial (8.22 ± 2.64 mmol L(-1)). Ratings of perceived exertion, fatigue and thermal sensation did not differ in the two trials (P > 0.05). CONCLUSION: Acute CIT ingestion induces alkalosis, water retention, plasma volume expansion and an increase in post-exercise blood lactate concentration, but does not improve 5,000-m running performance in a warm environment in non-heat-acclimated endurance-trained males.

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The aim of the present study was to evaluate the changes in glutathione redox ratio (GSSG·GSH(-1)) in red blood cells (RBCs) and whole blood in well-trained men following a ski marathon. 16 male subjects (27.0 ± 4.7 yrs, 1.81 ± 0.06 m, 77.6 ± 9.6 kg, VO2max 66.2 ± 5.7 ml·kg(-1)·min(-1)) were examined before the competition (pre- COMP), after the competition (post-COMP) and during an 18-hour recovery period (RECOV). There was a slight decrease in reduced glutathione (GSH) in blood and in RBCs in post-COMP. During RECOV, the GSH level in blood was reduced, the GSH level in RBCs was significantly elevated (a statistically significant difference as compared to the pre-COMP level). The post-COMP GSSG·GSH(-1) in full blood did not increase significantly, but its increase was statistically significant during the 18-hour recovery period. During the post-COMP and RECOV, the GSSG·GSH(-1) in RBCs slightly decreased in comparison with the pre-COMP. Vitamin C concentration in serum increased in post-COMP (49% vs. pre- COMP) and decreased to the baseline level during RECOV. In conclusion, our data show that acute exercise slightly increases the GSSG·GSH(-1) in whole blood, while GSSG·GSH(-1) in RBCs significantly decreases. Thus, exercise-related changes in the non-enzymatic components of the glutathione system (GSSG and GSH) in whole blood and RBCs are not identical. Key pointsThe glutathione system is a principal cellular non-enzymic antioxidant system in the organism. Long-term or high-intensity exercise may lead to a decreased level of reduced glutathione (GSH), and thereby increase the glutathione redox ratio (GSSG·GSH(-1)).Limited data are available about the glutathione redox (GSSG·GSH(-1)) status measured simultaneously in red blood cells (RBCs) and blood concerning acute high-intensity exercise.Acute high-intensity exercise slightly increases the GSSG·GSH(-1) in whole blood, while GSSG·GSH(-1) significantly decreases in RBCs.Our descriptive data show that exercise-induced changes in the non-enzymatic glutathione system seem to be more effective in RBCs and may prevent the damages resulting from reactive oxygen species during exercise.