Search Results (104)

Objectives: This study investigated the acute effects of pre-exercise cold-water immersion (CWI) on performance, muscle oxygen saturation, and mechanical muscle tension during calf raise training. Method: Twenty-four trained individuals (5 females, 19 males) were randomly assigned to either a CWI group (5 min at 10 ± 1 °C) or a non-CWI group (no intervention). Both groups performed three sets of standing calf raises to failure using a standardized protocol. Load lifted, repetitions, and rate of perceived exertion (RPE) were recorded. Muscle oxygenation (SmO₂, total hemoglobin) and mechanical muscle properties (frequency and stiffness) were measured before and after each set. Results: The CWI group showed a significantly greater increase in barbell load from set 1 to set 2 compared to the non-CWI group (from 94.5 ± 18.1 kg to 98.0 ± 18.7 kg, p < 0.01). Repetitions decreased and RPE increased across sets in both groups. The non-CWI group exhibited earlier increases in muscle stiffness and frequency, whereas these responses were delayed in the CWI group. Gastrocnemius SmO₂ increased during the protocol in the non-CWI group only. Total hemoglobin change was greater in the CWI group in set 1. Conclusions: These findings suggest that pre-exercise CWI may acutely enhance performance and delay neuromuscular fatigue without negatively affecting perceived effort. Full article

Cold-water immersion (CWI), as a common recovery method, has been widely used in the field of post-exercise fatigue recovery. However, there is still a lack of comprehensive and systematic scientific evaluation of the combined effects of cold-water immersion combined with other therapies (CWI + Other). The aim of this study was to compare the effects of CWI and CWI + Other in post-exercise fatigue recovery and to explore the potential benefits of CWI + Other. We systematically searched PubMed, Embase, Web of Science, Cochrane Library and EBSCO databases to include 24 studies (475 subjects in total) and performed a meta-analysis using standardized mean difference (SMD) and 95% confidence intervals (CIs). The results showed that both CWI + Other (SMD = −0.68, 95% CI: −1.03 to −0.33) and CWI (SMD = −0.37, 95% CI: −0.65 to −0.10) were effective in reducing delayed-onset muscle soreness (DOMS). In subgroup analyses of athletes, both CWI + Other (SMD = −1.13, 95% CI: −1.76 to −0.49) and CWI (SMD = −0.47, 95% CI: −0.87 to −0.08) also demonstrated significant effects. In addition, CWI + Other significantly reduced post-exercise C-reactive protein (CRP) levels (SMD = −0.62, 95% CI: −1.12 to −0.13), and CWI with water temperatures higher than 10 °C also showed a CRP-lowering effect (MD = −0.18, 95% CI: −0.30 to −0.07), suggesting a potential benefit in anti-inflammation. There were no significant differences between the two interventions in the metrics of creatine kinase (CK; CWI: SMD = −0.01, 95% CI: −0.27 to 0.24; CWI + Other: SMD = 0.26, 95% CI: −0.51 to 1.03) or countermovement jump (CMJ; CWI: SMD = 0.22, 95% CI: −0.13 to 0.57; CWI + Other: SMD = 0.07, 95% CI: −0.70 to 0.85). Full article

Postharvest losses and limited physiological knowledge restrict the conservation and year-round availability of underutilized crops such as Dioscorea trifida. This study characterized the postharvest behavior of Colombian purple D. trifida tubers and evaluated low-cost, GRAS-status technologies to improve storage performance in smallholder production systems. Tubers were stored for 34 days at ambient conditions (20 °C, 90% RH) and compared with treatments including cold storage, calcium pretreatments combined with Aloe vera-based coatings, and short-duration hot water immersion. Over storage, total carbohydrates increased, while potassium remained at substantial levels until the final day. Weight loss and respiration declined steadily, and sprouting was absent, suggesting extended endodormancy in this genotype. Major deterioration causes observed upon reception included fragmentation, insect damage, and surface molds, highlighting the importance of improved sanitation and mechanical protection during harvest, early postharvest stages, and transportation. Edible coatings enhanced antioxidant activity and increased malic and succinic acid concentrations. Cold storage at 3 °C reduced weight loss more effectively than storage at 12 or 20 °C, although citric acid accumulation was greater at the latter temperature. Among all treatments, immersion at 55 °C for 5 min was the most promising, offering a scalable, low-input option to extend shelf life in neglected yam species. Full article

Objective: This study aimed to evaluate the effects of cold-water immersion (CWI) on post-training recovery in Kung Fu athletes. Methods: In a 3-week crossover design, 16 Kung Fu athletes (22.00 ± 5.95 years, 76.90 ± 9.74 kg) were divided into two conditions: CWI and passive recovery as a control (CON) measure. Through the study, muscle damage markers (creatine kinase [CK], lactate dehydrogenase [LDH], aspartate aminotransferase [AST] and alanine aminotransferase [ALT]), physical performance tests (upper limbs power, SJ and CMJ), skin temperature (from lower and upper limbs), and skin temperature asymmetries were measured. Results: CWI resulted in a higher reduction of CK concentration than CON 24 h after the intervention (−21.32%; p < 0.001). The SJ height 24 h after the intervention was higher in the CWI than in the CON (p < 0.001). Both CWI and CON resulted in skin temperature returning to baseline levels 24 h after intervention. Conclusions: CWI was effective in restoring muscle power, reducing muscle damage and reducing body temperature (BT) in Kung Fu athletes. Cold water recovery showed better muscle power and strength 24 and 48 h after training when compared to the passive method. CK and skin temperature were better 24 h after cold water recovery. Full article

The psychological response to cold is complex. The present study aimed to determine if regular winter swimmers differed from those who did not practise winter swimming in terms of (1) daily perceived emotional states, (2) subjectively perceived satisfaction with life, and (3) hormone concentrations. An additional objective was to investigate how a single immersion in cold water in regular winter swimmers affected their subjectively assessed emotional states and levels of stress hormones. The study involved 30 males aged 30–50 years. The experimental group consisted of 15 males who regularly practised winter swimming. The control group (n = 15) had no contact with cold water. Three measurements were taken in the study: 24 h before cold-water immersion, immediately after coming out of the 4 °C water, and 24 h after cold-water immersion. Winter swimmers had significantly higher adrenaline levels than controls. Moreover, 24 h after cold-water immersion, the winter swimming group was characterized by a significant reduction in noradrenaline and adrenaline concentrations and a slight increase in cortisol concentration compared with the control group. Of interest, a slight increase in serotonin levels in the control group was observed, unlike in the winter swimming group. Dopamine levels remained unchanged. Full article

Wood adhesives play a critical role in the wood processing industry; however, traditional formaldehyde-based adhesives pose health risks and are reliant on non-renewable resources. This study aims to develop a bio-based wood adhesive with excellent water resistance, focusing on environmentally friendly solutions. The synthesis of an oxidized starch-lignin (OSTL) composite adhesive was accomplished by modifying starch via oxidation and subsequent cross-linking with lignin. Ammonium persulfate (APS) was employed for oxidation of starch, introducing aldehyde groups that upgrade its reactivity with lignin. Subsequently, the oxidized starch (OST) was cross-linked with the phenolic rings of lignin, resulting in a strong network structure. The oxidation of starch and its cross-linking mechanism with lignin were investigated using the Fourier transform infrared (FT-IR), proton nuclear magnetic resonance (1H-NMR), and X-ray photoelectron spectroscopy (XPS) techniques, proving the formation of aldehyde and carboxyl groups with subsequent reaction possibilities. The effects of oxidant dosage, oxidation time, and the ratio of starch to lignin on the adhesive properties were systematically studied. The results demonstrated that the OSTL adhesive, prepared under optimized conditions, exhibited outstanding adhesion strength (1.23 MPa in dry state) and water resistance (0.94 MPa after 24 h cold water immersion, 1.04 MPa after 3 h in hot water, and 0.69 MPa after 3 h in boiling water), significantly outperforming conventional wood adhesives in terms of cold water, hot water, and boiling water resistance. In addition, the thermal behavior of the OSTL adhesive was further validated using differential scanning calorimetry (DSC) as well as thermogravimetric analysis (TGA). This study presents new insights and technical support for the development of green, environmentally friendly, and highly water-resistant lignin-based bio-adhesives. Full article

Background/Objectives: The aim of this study was to assess the effects of cold-water immersion (CWI) post-eccentric muscle contraction exercise on skin temperature, pain score, maximum voluntary isometric contraction (MVIC), muscle damage, and muscle mechanical properties. Methods: Twenty-seven male participants (age 20.6 ± 0.6; body mass 69.4 ± 8.1; body fat % 13.7 ± 4.3) were divided into three treatments: whole-body CWI treatment group (n = 9), lower-body CWI treatment group (n = 9), and control treatment group (n = 9). Results: MVIC did not show a significant interaction effect between group and time but demonstrated a significant main effect for time (p = 0.001). The pain scale demonstrated a significant interaction effect between group and treatment (p = 0.049), in addition to significant main effects for both time and treatment (both p = 0.001). While blood creatine kinase (CK) concentration revealed no significant interaction effect between group and time, a significant main effect was observed for time (p = 0.001). Blood lactate dehydrogenase (LDH) concentration showed both a significant interaction effect between group and time (p = 0.02) and a significant main effect for time (p = 0.001). The tensiomyography (TMG) results for Dm showed a significant interaction effect between group and treatment (p = 0.047), as well as a significant main effect for time (p = 0.001). Conclusions: Lower-body CWI is effective in reducing pain indices and blood LDH levels, a marker of muscle damage. It may serve as an effective method for preventing and minimizing pain and muscle damage, comparable to whole-body CWI. Full article

Chronic cold exposure is a stressor that may adversely affect the hippocampal structure and cognitive function. Critical for memory formation and learning processes, the hippocampus is particularly susceptible to hypothalamic–pituitary–adrenal (HPA) axis activity and elevated glucocorticoid levels. Vitamin D plays a complex role in regulating mitochondrial function and may provide neuroprotection. This study aimed to investigate the effects of chronic cold exposure on proteins associated with signaling pathways, mitochondrial function, and oxidative stress in the hippocampus of rats and to evaluate the neuroprotective potential of vitamin D3 supplementation. Male Wistar rats (n = 26) were assigned to four groups: control (CON; n = 4), sham stress (WW; n = 6), chronic cold water immersion (CCWI) (CW group; n = 8), and CCWI with 600 IU/kg/day vitamin D3 (VD3) supplementation (CW + D group; n = 8). Exposure to CCWI significantly reduced the hippocampal mass of rats, an effect not reversed by vitamin D3 supplementation. However, vitamin D3 improved mitochondrial function and exhibited antioxidant effects, partially reducing markers of protein and lipid free radicals damage in neural tissue. Our findings demonstrate the antioxidant properties of VD3 and its potential role in mitigating hippocampal damage during prolonged cold exposure, although its neuroprotective effects remain limited. Full article

Residential water heating represents one of the most energy-intensive household applications, particularly in South Africa, where immersed resistive element heating dominates. Solar photovoltaic systems provide a promising solution for augmenting grid-based electrical water heaters, offering energy cost savings and environmental benefits. This study evaluates a novel approach to integrate solar photovoltaic directly into electrical water heater systems without using inverters. Using a combination of field experiments and simulation, four heating strategies were assessed, namely: “grid only”, “solar medium”, “solar heavy”, and “solar timer”. Metrics such as solar augmentation ratio, solar utilization, and cold event frequency were analyzed for different seasons using real-world and simulated water usage profiles. Results demonstrate significant grid energy reductions through solar augmentation, particularly in warmer seasons. However, the effectiveness of the strategies varies, with increased solar utilization often correlated with a higher frequency of cold events. A hybrid seasonal strategy is proposed to optimize energy savings while maintaining user comfort. This work highlights the potential of direct DC solar photovoltaic integration as a cost-effective and sustainable enhancement for residential water heating. Full article

Various protein-rich foods are traditionally immersed in virgin olive oil (VOO), a medium rich in phenols, which are health-promoting and sensorially important compounds. Immersing tofu in VOO may modify the sensory properties and nutritional value of both due to the oil’s hydrophilic phenol interactions with proteins and water. In this study, cubes of fresh tofu (T) (70% water) and freeze-dried tofu (FD-T) (5% water) were immersed in VOO for 7 days of cold storage. The changes in the phenolic compound content and standard quality parameters of the oil were noted after 1, 3, 5, and 7 days of contact with the tofu. The total phenols in the oil were determined using the Fast Blue BB assay, while single phenols were analyzed by HPLC-UV/VIS. During the 7 days, the total phenols in the oil decreased by up to 56% and 26% under the influence of fresh and freeze-dried tofu, respectively, including a significant decrease in hydroxytyrosol, oleacein, tyrosol, and oleocanthal. The water content and its release from fresh tofu significantly contributed to this decline. The degradation of the quality of the oil in contact with the fresh tofu was observed only in its sensory properties, with a marked reduction in the intensity of its fruitiness, bitterness and pungency. Full article

An important area of health is health promotion. A healthy lifestyle supports health improvement and early prevention of chronic diseases. Stimulation of the body by cold water swimming and swimming in a swimming pool can lead to adaptive changes beneficial for the human cardiovascular system. Within the winter swimming season of 2023/2024, for a period of 5 months, from November to March, once a week, study participants (n = 30; n = 15 females and n = 15 males) from the Krakow Society of Winter Swimmers ‘Kaloryfer’ in Krakow (Poland) practiced winter swimming in cold water (4–5 °C) and swam in the sports pool of the University of Physical Culture in Krakow in water at a temperature of 28 °C. After a full season of winter swimming and swimming pool sessions, both males and females exhibited a tendency towards lower erythrocyte (p = 0.002), leukocyte (p < 0.001), and platelet counts (p < 0.001), as well as an increase in blood plasma viscosity (within normal limits) (p = 0.001), without any changes in blood aggregation or fibrinogen indicators. The remaining morphological indicators and the elongation index demonstrated only limited variation. Winter swimming induces positive changes in blood morphology and rheology. Full article

(1) Background: The recovery method is important and decisive in the training system. This study aimed to assess the effects of various post-training recovery methods on muscle damage and strength indicators in Paralympic powerlifting athletes. (2) Methods: A crossover study was conducted involving eleven male athletes (25.4 ± 3.3 years, 70.3 ± 12.1 kg). Muscle damage was assessed using blood biochemical markers (cytokines IL-6, IL-10, and TNF-α) and isometric force indicators, including the maximum isometric force (MIF), time to MIF, and Rate of Force Development. The following assessments were performed before, immediately after, and at 24 and 48 h after the recovery protocol: (a) passive recovery (RP) or (b) cold-water immersion (CWI). (3) Results: The main results indicated that maximum isometric force (MIF) significantly improved after 48 h of CWI application (p < 0.05; for all comparison). The analysis of biochemical markers did not yield significant differences between the recovery methods at different time points (p > 0.05). For IL-6, there were significant differences between CWI before (2.29 ± 1.08, 95% CI 1.57–3.01) and CWI 2 h later (2 h) (4.59 ± 2.96, 95% CI 2.60–6.57; p = 0.045), and between CWI 15 min later (15 min) (4.14 ± 2.24, 95% CI 2.63–5.64) and CWI 48 h later (48 h) (2.33 ± 1.25, 95% CI 1.49–3.17; p = 0.034). There were differences between CWI 2 h (4.14 ± 2.24, 95% CI 2.63–5.64) and CWI 48 h later (2.33 ± 1.25, 95% CI 1.49–3.17; p = 0.035; F = 9.202; η²p = 0.479; high effect). (4) Conclusions: CWI significantly improved the post-resistance training muscle damage and strength in Paralympic powerlifting athletes. Full article

The degradation of rubber materials under environmental and mechanical stress presents a significant challenge, particularly due to UV (ultraviolet light) exposure, which severely impacts the material’s physical properties. This study aims to enhance the UV stability and longevity of rubber by evaluating the performance of modified polyurethane and silicone coatings as protective stabilizers. Natural rubber—styrene–butadiene rubber (NR-SBR), known for its exceptional mechanical properties, was selected as the base material. To ensure strong adhesion, cold atmospheric plasma treatment was applied, increasing the surface energy by 250%, primarily through an enhancement of the polar component. After treatment, supplier-recommended coatings were applied and tested for adhesion using the pull-out method. Aging tests under UV exposure, water immersion, and high temperatures were conducted to assess durability, with tensile tests used to monitor changes over time. Coatings exhibiting cracking after UV exposure were excluded from further analysis. A silicone coating demonstrating superior moisture resistance and durability under extreme conditions was identified as a promising candidate for future UV stabilization applications. These findings provide a foundation for developing advanced coatings to significantly extend the service life of rubber materials in demanding environments. Full article

This review emphasises the importance of the cardiovascular response to facial cooling (FC) and breath holding in both sexes. The trigemino-cardiac reflex, triggered by FC, reduces heart rate (HR) and constricts blood vessels. When combined with breath holding, this effect intensifies, enhancing the cardiodepressive impact. The cardiovascular reaction to this combination, known as the cold-water face immersion or simulated diving test, varies among individuals and depends on their cardiovascular regulatory profiles, which differ between men and women. Despite extensive research on the cardiovascular response to FC and apnoea, most studies did not categorise participants by sex, leading to a limited understanding of how it influences trigeminal nerve stimulation (TGS) and breath-hold diving (BHD). Despite attempts to address this, the existing findings remain inconsistent due to intra- and inter-individual variability. Key factors influencing the diving response include the influence of the parasympathetic system on HR, vascular sympathetic activity affecting total peripheral resistance (TPR), sensitivity to CO₂, lung capacity, training, physical performance, duration of apnoea, and the stimulation of metaboreceptors in working muscles. These factors differ between men and women, potentially contributing to variations in the effectiveness of the response to the FC combined with breath holding. Full article

There is an urgent need for the cryopreservation of dormant buds to conserve the genetic resources of woody plants, particularly fruit trees, as this method is less time-consuming and relatively inexpensive. In the present study, three different cryopreservation protocols were tested on dormant buds from three varieties of Vitis amurensis Rupr. The explants were collected between November 2017 and March 2018. Twig segments harvested from field-grown plants, each containing one dormant bud, were desiccated in a low-temperature test chamber at −5 °C. The viability of the buds was highest (45%) after 28–30 days of desiccation, when the moisture content was approximately 25–30%. Cryopreservation using the CP3 protocol (which involves decreasing the temperature at a rate of 0.1 °C/min to −30 °C and holding this temperature for 24 h, followed by a 0.5 °C/min decline to −80 °C, a 1 °C/min decline to −180 °C, and finally reaching −196 °C in a CryoMed controlled rate freezer) significantly enhanced the viability (66.67%) when the samples were packed in aluminum-foil bags. Additionally, immersing the twigs in ice-cold (4 °C) water for 24 h in a refrigerator during thawing proved to be more conducive to viability. The dormant buds of all three V. amurensis varieties collected in January exhibited the highest viability after cryopreservation, followed by those collected in February and December. In contrast, the dormant buds collected in November and March showed the lowest viability after cryopreservation. The average viability of twigs of ‘Shuanghong’, ‘Zuoshanyi’, and ‘Shuangfeng’ collected between 2019 and 2021 all exceeded 60%. After the cryopreservation process, the outer multilayered cells in the buds were completely damaged; however, the inner cells exhibited moderate damage and were able to resume growth after thawing. Therefore, based on graft viability and histological observations, the dormant bud cryopreservation protocols tested in this study could be applicable to these three V. amurensis varieties. Full article