What is the effect of vigorous exercise on the brain?

Abstract Aims: This study aimed to verify whether vigorous exercise is capable of generating mental fatigue. Methods: To do so, 16 young adult male (29.4 ± 5.2 years old) cyclists (5.4 ± 4.6 years of training) underwent three visits: 1) control session (rest); 2) session with cognitive demand (20 minutes of AX-CPT); 3) session with vigorous exercise (10km time trial). Mental fatigue was assessed using the visual analog scale of fatigue in the pre-and post-session moments. A two-way ANOVA of repeated measures followed by the Bonferroni posthoc was used to verify the effect of the condition (control, cognitive demand, and exercise) and time (pre and post) interaction. The paired "t" test was used to compare the delta of mental fatigue (post - pre) of the sessions. The partial eta squared was used to determine the effect size of the variance. The significance adopted was p < 0.05. Results: A condition x time interaction was observed (F (2.30) = 5.349, p = 0.010, partial η2 = 0.263). When comparing the deltas, a mean difference was found between the control and vigorous exercise (p = 0.033) conditions and cognitive demand and vigorous exercise (p = 0.017) conditions. Control and cognitive demand sessions showed no difference (p = 0.801). Conclusion: The findings suggest that intense physical exercise seems to cause mental fatigue after practice.

Research Advancements in Motor Function and Biomechanical Characteristics of Achilles Tendon / 医用生物力学

Achilles tendon is the key structure to connect the heel and foot plantar flexors and transmit the force from the leg triceps muscle, which is the key to storing and releasing energy storage during running and jumping. At present, the primary causes of Achilles tendon injury are non-homologous loading during stance phase and deficient recovery after overload. However, the relevant measures to prevent Achilles tendon injury cannot achieve full recovery. This paper reviewed the research progress of Achilles tendon’s motor function and its application in biomechanics domestically and internationally, reconsidering the role of Achilles tendon in human running and jumping which included anatomical structure of the Achilles tendon, the relationship between internal force and external force, and the effective training program. The key for future research on motor function of Achilles tendon is to improve its mechanical properties, keep the increased load in a better range and ultimately improve motion performance and reduce sports injury from the source.

Exercicio Aerobio Intervalado Induz Maior Reducao na Sobrecarga Cardiaca na Recuperacao em Ratos / Aerobic Interval Exercise Training Induces Greater Reduction in Cardiac Workload in the Recovery Period in Rats

Fundamento: O treinamento aeróbio intervalado produz maior benefício na função cardiovascular comparado ao treinamento aeróbio contínuo. Objetivo: O presente estudo teve como objetivo analisar os efeitos de ambas as modalidades nas respostas hemodinâmicas de ratos sadios. Métodos: Ratos machos foram distribuídos aleatoriamente em três grupos: exercício contínuo (EC, n = 10); exercício intervalado (EI, n = 10); e controle (C, n = 10). A sessão do grupo EC consistiu em 30 min à intensidade de 50% da velocidade máxima (Vel Máx). O grupo EI realizou 30 min, incluindo três períodos de 4 min a 60% da Vel Máx intercalados com 4 min de recuperação a 40% da Vel Máx. Frequência Cardíaca (FC), Pressão Arterial (PA) e Duplo Produto (DP) foram medidos antes, durante e após o exercício. Resultados: Os grupos EC e EI apresentaram aumento da PA sistólica e DP durante o exercício em comparação ao repouso. Após o término do exercício, o grupo EC mostrou menor resposta da PA sistólica e do DP em relação ao repouso, enquanto o grupo EI apresentou menor PA sistólica e PA média. No entanto, somente no grupo EI a FC e o DP apresentaram menor resposta na recuperação. Conclusão: Uma sessão de exercício intervalado em ratos sadios induziu respostas hemodinâmicas similares durante o exercício às obtidas em exercício contínuo. Na recuperação, o exercício intervalado promoveu maiores reduções no esforço cardíaco do que em sessões contínuas de exercício. .

Background: Aerobic interval exercise training has greater benefits on cardiovascular function as compared with aerobic continuous exercise training. Objective: The present study aimed at analyzing the effects of both exercise modalities on acute and subacute hemodynamic responses of healthy rats. Methods: Thirty male rats were randomly assigned into three groups as follows: continuous exercise (CE, n = 10); interval exercise (IE, n = 10); and control (C, n = 10). Both IE and CE groups performed a 30-minute exercise session. The IE group session consisted of three successive 4-minute periods at 60% of maximal velocity (Max Vel), with 4-minute recovery intervals at 40% of Max Vel. The CE group ran continuously at 50% of Max Vel. Heart rate (HR), blood pressure(BP), and rate pressure product (RPP) were measured before, during and after the exercise session. Results: The CE and IE groups showed an increase in systolic BP and RPP during exercise as compared with the baseline values. After the end of exercise, the CE group showed a lower response of systolic BP and RPP as compared with the baseline values, while the IE group showed lower systolic BP and mean BP values. However, only the IE group had a lower response of HR and RPP during recovery. Conclusion: In healthy rats, one interval exercise session, as compared with continuous exercise, induced similar hemodynamic responses during exercise. However, during recovery, the interval exercise caused greater reductions in cardiac workload than the continuous exercise. .

18-1 Effects of bathing containing artificial carbon dioxide and sodium chloride on several different symptoms: different of acute and chronic effects / 日本温泉気候物理医学会雑誌

Purpose: We have previously reported the physiological and biochemical effects of bath salts. In this study, we used bath additive containing artificial carbon dioxide and sodium chloride (S bath additive), and the acute effects of bathing once with S bath additive and chronic effects of daily bathing with S bath additive for 15 consecutive days were compared with the effects of bathing once in plain water. Improvement in 10 symptoms was investigated using a 5-point verbal rating scale (VRS). Methods: Nine patients aged 51-82 years (mean, 66.6 years) with cold intolerance and lower leg pain were treated with balneotherapy. Whole-body bathing at 40°C was performed for 10 min daily (day 1, bathing in plain water; days 2-16, bathing with S bath additive). On days 1, 2, and 16, changes in patient’s subjective symptoms were evaluated using a VRS ranging from -1 to +3. Results: Compared with bathing once in plain water, bathing once with S bath additive was improvement of coldness, body warmth, blood circulation promotion, limb warmth, lightness of foot, and coldness in limbs. Daily bathing with S bath additive for 15 days significantly improved all symptoms compared with bathing in plain water. A comparison between single and daily bathing with S bath additive showed that relieving fatigue and lumbago were significantly improved after consecutive bathing, demonstrating the benefits of long-term usage. Discussion: Bathing once with S bath additive had acute effects on symptoms associated with peripheral circulation, such as coldness in limbs, body warmth, and limb warmth. Daily bathing with S bath additive improved bone- and joint-related symptoms, such as lumbago and shoulder stiffness, demonstrating that the chronic effects of S bath additive differ from the acute ones. These results are consistent with previous studies on natural hot springs which found that the efficacy of short-term treatment was distinct from that obtained after >2 weeks of treatment.

18-1Effects of bathing containing artificial carbon dioxide and sodium chloride on several different symptoms: different of acute and chronic effects / 日本温泉気候物理医学会雑誌

<b>Purpose: </b>We have previously reported the physiological and biochemical effects of bath salts. In this study, we used bath additive containing artificial carbon dioxide and sodium chloride (S bath additive), and the acute effects of bathing once with S bath additive and chronic effects of daily bathing with S bath additive for 15 consecutive days were compared with the effects of bathing once in plain water. Improvement in 10 symptoms was investigated using a 5-point verbal rating scale (VRS).<BR><b>Methods:</b> Nine patients aged 51-82 years (mean, 66.6 years) with cold intolerance and lower leg pain were treated with balneotherapy. Whole-body bathing at 40°C was performed for 10 min daily (day 1, bathing in plain water; days 2-16, bathing with S bath additive). On days 1, 2, and 16, changes in patient’s subjective symptoms were evaluated using a VRS ranging from -1 to +3.<BR><b>Results:</b> Compared with bathing once in plain water, bathing once with S bath additive was improvement of coldness, body warmth, blood circulation promotion, limb warmth, lightness of foot, and coldness in limbs. Daily bathing with S bath additive for 15 days significantly improved all symptoms compared with bathing in plain water. A comparison between single and daily bathing with S bath additive showed that relieving fatigue and lumbago were significantly improved after consecutive bathing, demonstrating the benefits of long-term usage.<BR><b>Discussion: </b>Bathing once with S bath additive had acute effects on symptoms associated with peripheral circulation, such as coldness in limbs, body warmth, and limb warmth. Daily bathing with S bath additive improved bone- and joint-related symptoms, such as lumbago and shoulder stiffness, demonstrating that the chronic effects of S bath additive differ from the acute ones. These results are consistent with previous studies on natural hot springs which found that the efficacy of short-term treatment was distinct from that obtained after >2 weeks of treatment.

Repercussões da radioterapia na região orofacial e seu tratamento / Impact of radiotherapy on the orofacial region and management of related conditions

A radioterapia em região de cabeça e pescoço provoca inúmeras sequelas ao paciente irradiado, afetando o sistema estomatognático e com repercussões sistêmicas importantes. As sequelas da radiação ionizante podem ser extensas e, algumas vezes, permanentes, em especial nas glândulas salivares e no tecido ósseo. É relevante que o cirurgião dentista tenha conhecimento das reações adversas e das formas adequadas de prevenção e tratamento para amenizar o desconforto e melhorar a condição de vida do paciente irradiado. Portanto, a conscientização e motivação deste paciente, com a promoção de saúde oral através da adequação do meio bucal e orientações sobre ações preventivas, são essenciais para se obter o melhor prognóstico.

Head and neck radiotherapy causes countless sequelae in irradiated patients, affecting the stomatognathic system, with significant systemic implications. Sequelae of exposure to ionizing radiation may be extensive and sometimes permanent, particularly in the salivary glands and bone tissue. It is of utmost importance that the surgeon dentist be aware of adverse reactions and appropriate forms of treatment to alleviate discomfort and improve the quality of life of the irradiated patient. Therefore, awareness and motivation of the patient, with promotion of oral health through the adaptation of the oral environment and guidance on preventive measures are essential to get a better prognosis.

Acute intraperitoneal mercury chloride contamination and distribution in liver, muscle and gill of a neotropical fish Hoplias malabaricus (BLOCK, 1794)

The present study investigated with the distribution of mercury chloride in muscle, liver and gills of Hoplias malabaricus contaminated through intraperitoneal injection (6 µg in 0.1mL of PBS) for a period of 24, 48, 72 and 96h. The liver, gill and muscle were analyzed for mercury content in an ICP/AES (Varian Liberty II) with vapor generating accessory (VGA 77). The muscle and liver tissues presented the same contamination pattern increasing concentrations in 24 h of exposure with a decrease in Hg concentration with 72 h and a new increase in Hg concentrations with 96 h of exposure. The Hg concentrations in contaminated organisms were always higher than the control although only for liver samples the difference was statistically significant. Liver samples always presented higher Hg contents when compared with gill and muscle samples.

Acute effects of deep breathing for a short duration (2-10 minutes) on pulmonary functions in healthy young volunteers.

Breathing is the most vital function for maintenance of life. Slow and deep breathing is an integral part of Pranayama and it reduces dead space ventilation and renews air throughout the lungs. The reported beneficial effects of deep breathing as a part of either long term or short term practice of pranayama are well documented. However our knowledge about the effects of a few minutes’ of deep breathing on human ventilatory parameters is poor. In the present study, we examined the relationship between exposure to short duration of deep breathing and performance on Pulmonary Function Tests before and after the deep breathing. The study was conducted in a homogenous group of 12 volunteers containing 4 females and 8 males who were well trained in pulmonary function testing (PFT) before the start of the study. The volunteers performed deep breathing (DB) exercise for 2, 5 and 10 minutes at the rate of 6 breaths per minute under guidance, and the duration of DB exercise for that day was randomly selected for each group. PFT was done before and after the DB exercise. There was a significant (P<0.05) increase in vital capacity (VC) after 2 and 5 minutes’ DB exercise and a consistent improvement in tidal volume (TV) and minute ventilation (MV) after the DB exercise in all the three groups, though it wasn’t statistically significant. There was a significant (P<0.05) increase in forced vital capacity (FVC) after 2 minutes’ of DB exercise and a consistent increase in all the three groups in forced inspiratory vital capacity (FIVC) and peak inspiratory flow rate (PIFR), though this increase was not statistically significant. This shows that deep breathing exercise, even for a few minutes’ duration is beneficial for the lung functions.

Ambient particulate air pollution from vehicles promotes lipid peroxidation and inflammatory responses in rat lung

Oxidative stress plays a major role in the pathogenesis of particle-dependent lung injury. Ambient particle levels from vehicles have not been previously shown to cause oxidative stress to the lungs. The present study was conducted to a) determine whether short-term exposure to ambient levels of particulate air pollution from vehicles elicits inflammatory responses and lipid peroxidation in rat lungs, and b) determine if intermittent short-term exposures (every 4 days) induce some degree of tolerance. Three-month-old male Wistar rats were exposed to ambient particulate matter (PM) from vehicles (N = 30) for 6 or 20 continuous hours, or for intermittent (5 h) periods during 20 h for 4 consecutive days or to filtered air (PM <10 mum; N = 30). Rats continuously breathing polluted air for 20 h (P-20) showed a significant increase in the total number of leukocytes in bronchoalveolar lavage compared to control (C-20: 2.61 x 105 ± 0.51;P-20: 5.01 x 105 ± 0.81; P < 0.05) and in lipid peroxidation ([MDA] nmol/mg protein: C-20: 0.148 ± 0.01; P-20: 0.226 ± 0.02; P < 0.05). Shorter exposure (6 h) and intermittent 5-h exposures over a period of 4 days did not cause significant changes in leukocytes. Lipid damage resulting from 20-h exposure to particulate air pollution did not cause a significant increase in lung water content. These data suggest oxidative stress as one of the mechanisms responsible for the acute adverse respiratory effects of particles, and suggest that short-term inhalation of ambient particulate air pollution from street with high automobile traffic represents a biological hazard.

Acute Response to Co-60 Total Body Irradiation (TBI) With 600 cgy at 3 Different Does Rates in the Mice / 대한치료방사선과학회지

The acute effects of variable dos rates to total body irradiation (TBI) were investigated with 600 cgy of single exposure in the mice as a preclinical model. Total 80 mice (ICR) were used. Twenty of which served as controls, receiving no irradiation. All irradiated mice showed a universal decline in their weight and white blood cell count. The degree of weight loss and leukopenia were similar at 3 different dos rate but slightly prominent with 15 cgy/minute group. The degree of recovery among the groups showed no dose rate dependence. Our results suggest that TBI with 15 cgy/minute may be applicable for clinical therapy with careful evaluation of patient's condition.