Lower head temperature does not affect children's self-paced running velocity.

To test if the use of a peaked cap protects children against sun radiation, allowing increased exercise performance, nineteen healthy children (10.3 ± 0.8 years old, 146.2 ± 6.9 cm, 36.8 ± 5.5 kg, 1.2 ± 0.1 m2 and 44.1 ± 2.8 mL.kg-1.min-1) took part in 4 experimental situations: 2 initial familiarization runs and 2 self-paced 6km runs (4 × 1.5 km exercise bouts with 3min rest intervals) one of them wearing a peaked cap (CAP) and another situation without the cap (NOCAP). The CAP and NOCAP situations were randomized. Exercise was performed outdoors 3-7 days apart. Environmental variables were measured every 10min, and physiological variables were measured before and after each run and during the rest intervals. Running velocity did not differ between CAP and NOCAP situations. The mean head temperature was reduced by 1.1 °C in the CAP situation (p < .05). Average skin temperature, mean heart rate, rate of perceived exertion and wet bulb and globe temperature did not differ between CAP and NOCAP. The decrease in the mean head temperature was not sufficient to alter running velocity.

Surgical management of acute sigmoid diverticulitis.

INTRODUCTION: Medical therapy is usually indicated for uncomplicated diverticulitis. Indications for surgery include recurrent attacks and complications of the disease. This study describes our experience in the surgical treatment of acute sigmoid diverticulitis. METHODS: Between 2001 and 2006, 82 patients were operated for acute sigmoid diverticulitis. RESULTS: The indications for surgery included recurrent diverticulitis (7 patients), Hinchey stages I or II (28 patients), Hinchey stages III or IV (34 patients), diverticular colonic stricture (8 patients), diverticular bleeding (3 patients) and colovescical fistulae (2 patients). Of our 82 patients with surgical treatment, 77 with acute inflammatory complications have been analysed. 43 of them (55.9%) were treated by the Hartmann's procedures, and 34 (44.1%) by primary colonic resection-anastomosis. Hartmann's operation was performed in 5 of 28 (17.9%) patients with Hinchey stages I or II with elevated comorbidity, in all 34 patients with Hinchey stages III or IV and in 4 of 8 patients (50%) with diverticular stricture. Primary colonic resections-anastomosis was performed in all 7 patients with recurrence of diverticulitis, in 23 of 28 patients (82.1%) with Hinchey stages I or II, and in 4 of 8 (50%) patients with diverticular stricture. The overall perioperative mortality rate was 7.8%. The overall perioperative morbidity rate was 18.2%. CONCLUSION: According to the data obtained from our experience and considering the current literature on the topic, the primary colonic resection-anastomosis represents the first choice intervention in stages I-II. The Hartmann's procedure confirms its effectiveness in stages III-IV.

T-Shirt fabric and color affect the physiological strain but not 10 km outdoor running performance.

BACKGROUND: The aim of the present study was to evaluate the effects of T-Shirt fabric and color on the 10 km outdoor running performance. METHODS: Six men and six women (mean±SD: age: 27±5 years; height: 1.70±0.13 m; weight: 64.0±12.7 kg; body surface area: 1.73±0.29 m2; Σskinfolds: 107±24 mm; VO2max: 40.2±8.4 mL.kg-1.min-1) took part in five experimental trials, during each of which they wore: 1) no T-shirt (CON); 2) white polyester T-shirt (WP); 3) black polyester T-shirt (BP); 4) white cotton T-shirt (WC); and 5) black cotton T-shirt (BC). Average running velocity (pace) was calculated from each 2 km running time. Rectal, skin and T-shirt temperatures, heart rates and Physiological Strain Index (PSI) were measured before and after the 10 km runs and at the end of each 2 km. RESULTS: There were no differences in pace, heart rate, rectal and skin temperatures among conditions (P>0.05). PSI was higher in BC and WC conditions when compared to BP and WP conditions. T-shirt temperature was higher for the BC when compared to WP, BP and WC conditions. Rectal temperature and heart rate increased simultaneously with reduced pace throughout self-paced running (P<0.05). CONCLUSIONS: Despite fabric type T-shirt altered PSI, running performance in the 10 km run was not affected by T-shirt type or color.

Effects of human head hair on performance and thermoregulatory responses during 10-km outdoor running in healthy men / Efeitos do cabelo da cabeça humana no desempenho e na resposta termorregulatória durante a corrida de 10 km ao ar livre em homens saudáveis

Abstract The aim of the present study was to evaluate the effects of human head hair on performance and thermoregulatory responses during 10-km outdoor running in healthy men. Twelve healthy males (29.5 ± 3.7 years, 174.9 ± 4.3 cm, 72.7 ± 3.2 kg and VO2max 44.6 ± 3.4 ml.kg-1.min-1) participated in two self-paced outdoor 10-km running trials separated by 7 days: 1) HAIR, subjects ran with their natural head hair; 2) NOHAIR, subjects ran after their hair had been totally shaved. Average running velocity was calculated from each 2-km running time. Rectal temperature, heart rate and physiological strain index were measured before and after the 10-km runs and at the end of each 2 km. The rate of heat storage was measured every 2 km. The environmental stress (WBGT) was measured every 10 min. The running velocity (10.9 ± 1 and 10.9 ± 1.1 km.h-1), heart rate (183 ± 10 and 180 ± 12 bpm), rectal temperature (38.82 ± 0.29 and 38.81 ± 0.49oC), physiological strain index (9 ± 1 and 9 ± 1), or heat storage rate (71.9 ± 64.1 and 80.7 ± 56.7 W.m-1) did not differ between the HAIR and NOHAIR conditions, respectively (p>0.05). There was no difference in WBGT between the HAIR and NOHAIR conditions (24.0 ± 1.4 and 23.2 ± 1.5ºC, respectively; p=0.10). The results suggest that shaved head hair does not alter running velocity or thermoregulatory responses during 10-km running under the sun.

Resumo O objetivo do presente estudo foi avaliar os efeitos do cabelo da cabeça humana no desempenho e na resposta termorregulatória durante 10 km de corrida ao ar livre em homens saudáveis. Doze saudável do sexo masculino (29,5 ± 3,7 anos, 174,9 ± 4,3 cm, 72,7 ± 3,2 kg e VO2máx 44,6 ± 3,4 ml.kg-1.min-1) participaram de 2 corridas de 10km separadas por 7 dias de intervalo em ritmo auto regulado: 1) HAIR- voluntários correram com seus cabelos intactos, 2) NOHAIR- voluntários correrram após terem seus cabelos totalmente raspado. A velocidade média da corrida foi calculada a cada série de 2 km. Temperatura retal, freqüência cardíaca e índice de estresse fisiológico foram medidos antes e depois dos 10 km da corrida e no fim de cada 2 km. Taxa de armazenamento de calor foi medida a cada 2 km. Além disso, o estresse ambiental (WBGT) foi medido a cada 10 min. A velocidade de corrida (10,9 ± 1 e 10,9 ± 1,1 km.h-1: freqüência cardíaca (183 ± 10 e 180 ± 12 bpm), temperatura retal (38,82 ± 0,29 e 38,81 ± 0,49º C), índice estresse fisiológico (9 ± 1 e 9 ± 1) e taxa de armazenamento de calor (71,9 ± 64,1 e 80,7 ± 56,7 Wm-1), não foi diferente entre as situações HAIR e NOHAIR, respectivamente (p>0,05). Não houve diferença no WBGT entre HAIR e NOHAIR (24,0 ± 1.4º C e 23,2 ± 1,5º C, respectivamente; p=0,10). Os resultados sugerem que raspar o cabelo da cabeça não altera a velocidade da corrida e as respostas termorregulatórias durante 10 km de corrida sob o sol.

Fat-free mass change after nutritional rehabilitation in weight losing COPD: role of insulin, C-reactive protein and tissue hypoxia.

BACKGROUND: Fat-free mass (FFM) depletion marks the imbalance between tissue protein synthesis and breakdown in chronic obstructive pulmonary disease (COPD). To date, the role of essential amino acid supplementation (EAAs) in FFM repletion has not been fully acknowledged. A pilot study was undertaken in patients attending pulmonary rehabilitation. METHODS: 28 COPD patients with dynamic weight loss > 5% over the last 6 months were randomized to receive EAAs embedded in a 12-week rehabilitation program (EAAs group n = 14), or to the same program without supplementation (C group n = 14). Primary outcome measures were changes in body weight and FFM, using dual X-ray absorptiometry (DEXA). RESULTS: At the 12th week, a body weight increment occurred in 92% and 15% of patients in the EAAs and C group, respectively, with an average increase of 3.8 +/- 2.6 kg (P = 0.0002) and -0.1 +/- 1.1 kg (P = 0.81), respectively. A FFM increment occurred in 69% and 15% of EAAs and C patients, respectively, with an average increase of 1.5 +/- 2.6 kg (P = 0.05) and -0.1 +/- 2.3 kg (P = 0.94), respectively. In the EAAs group, FFM change was significantly related to fasting insulin (r(2) 0.68, P < 0.0005), C-reactive protein (C-RP) (r(2) = 0.46, P < 0.01), and oxygen extraction tension (PaO(2x)) (r(2) = 0.46, P < 0.01) at end of treatment. These three variables were highly correlated in both groups (r > 0.7, P < 0.005 in all tests). CONCLUSIONS: Changes in FFM promoted by EAAs are related to cellular energy and tissue oxygen availability in depleted COPD. Insulin, C-RP, and PaO(2x) must be regarded as clinical markers of an amino acid-stimulated signaling to FFM accretion.

Thermoregulatory efficiency is increased after heat acclimation in tropical natives.

To evaluate the effects of heat acclimation on sweat rate redistribution and thermodynamic parameters, 9 tropical native volunteers were submitted to 11 days of exercise-heat exposures (40+/-0 degrees C and 45.1+/-0.2% relative humidity). Sudomotor function was evaluated by measuring total and local (forehead, chest, arm, forearm, and thigh) sweat rates, local sweat sodium concentration, and mean skin and rectal temperatures. We also calculated heat production (H), heat storage (S), heat exchange by radiation (R) and by convection (C), evaporated sweat (E(sw)), sweating efficiency (eta(sw)), skin wettedness (w(sk)), and the ratio between the heat storage and the sum of heat production and heat gains by radiation and convection (S/(H+R+C)). The heat acclimation increased the whole-body sweat rate and reduced the mean skin temperature. There were changes in the local sweat rate patterns: on the arm, forearm, and thigh it increased significantly from day 1 to day 11 (all p<0.05) and the sweat rates from the forehead and the chest showed a small nonsignificant increase (p=0.34 and 0.17, respectively). The relative increase of local sweat rates on day 11 was not different among the sites; however, when comparing the limbs (arm, forearm, and thigh) with the trunk (forehead and chest), there was a significant higher increase in the limbs (32+/-5%) in comparison to the trunk (11+/-2%, p=0.001). After the heat acclimation period we observed higher w(sk) and E(sw) and reduced S/(H+R+C), meaning greater thermoregulatory efficiency. The increase in the limb sweat rate, but not the increase in the trunk sweat rate, correlated with the increased w(sk), E(sw), and reduced S/(H+R+C) (p<0.05 to all). Altogether, it can be concluded that heat acclimation increased the limbs' sweat rates in tropical natives and that this increase led to increased loss of heat through evaporation of sweat and this higher sweat evaporation was related to higher thermoregulatory efficiency.

Heat and exercise acclimation increases intracellular levels of Hsp72 and inhibits exercise-induced increase in intracellular and plasma Hsp72 in humans.

In order to verify the effects of heat and exercise acclimation (HA) on resting and exercise-induced expression of plasma and leukocyte heat shock protein 72 (Hsp72) in humans, nine healthy young male volunteers (25.0 ± 0.7 years; 80.5 ± 2.0 kg; 180 ± 2 cm, mean ± SE) exercised for 60 min in a hot, dry environment (40 ± 0°C and 45 ± 0% relative humidity) for 11 days. The protocol consisted of running on a treadmill using a controlled hyperthermia technique in which the work rate was adjusted to elevate the rectal temperature by 1°C in 30 min and maintain it elevated for another 30 min. Before and after the HA, the volunteers performed a heat stress test (HST) at 50% of their individual maximal power output for 90 min in the same environment. Blood was drawn before (REST), immediately after (POST) and 1 h after (1 h POST) HST, and plasma and leukocytes were separated and stored. Subjects showed expected adaptations to HA: reduced exercise rectal and mean skin temperatures and heart rate, and augmented sweat rate and exercise tolerance. In HST1, plasma Hsp72 increased from REST to POST and then returned to resting values 1 h POST (REST: 1.11 ± 0.07, POST: 1.48 ± 0.10, 1 h POST: 1.22 ± 0.11 ng mL(-1); p < 0.05). In HST2, there was no change in plasma Hsp72 (REST: 0.94 ± 0.08, POST: 1.20 ± 0.15, 1 h POST: 1.17 ± 0.16 ng mL(-1); p > 0.05). HA increased resting levels of intracellular Hsp72 (HST1: 1 ± 0.02 and HST2: 4.2 ± 1.2 density units, p < 0.05). Exercise-induced increased intracellular Hsp72 expression was observed on HST1 (HST1: REST, 1 ± 0.02 vs. POST, 2.9 ± 0.9 density units, mean ± SE, p < 0.05) but was inhibited on HST2 (HST2: REST, 4.2 ± 1.2 vs. POST, 4.4 ± 1.1 density units, p > 0.05). Regression analysis showed that the lower the pre-exercise expression of intracellular Hsp72, the higher the exercise-induced increase (R = -0.85, p < 0.05). In conclusion, HA increased resting leukocyte Hsp72 levels and inhibited exercise-induced expression. This intracellular adaptation probably induces thermotolerance. In addition, the non-increase in plasma Hsp72 after HA may be related to lower stress at the cellular level in the acclimated individuals.

C-reactive protein correlates with tissue oxygen availability in patients with stable COPD.

BACKGROUND: Arterial oxygen tension, oxygen delivery to tissue, and systemic inflammation are recognized as pivotal factors in the progression of chronic obstructive pulmonary disease (COPD). However, interconnections between systemic inflammation and tissue oxygen availability are scantly investigated. Tissue oxygen availability depends on arterial PaO2, oxygen concentration, hemoglobin oxygen affinity (P50), and hemoglobin oxygen binding capacity (ceHb). As the integrated changes of those indices are summarized by oxygen extraction tension (PaO2x), the objective of this study was to explore the association between C-reactive protein (CRP) blood levels and either PaO2x or each of its determinants, in stable COPD. MATERIALS AND METHODS: Blood CRP and oxygen status of arterial blood were measured at rest while breathing room air in 44 moderate to severe stable COPD patients. PaO2x was calculated along the shape of oxygen binding curve as the oxygen tension resulting from removal of 2.3 mmol of oxygen per liter of blood. Multiple linear regression analysis was performed with PaO2, ceHb, and P50 as independent variables, and CRP as the dependent variable, adjusting for age and sex. The analysis was repeated using PaO2x as a sole independent variable. RESULTS: Multiple linear regression analysis indicated that ceHb, PaO2, and P50, were significant and independent predictors of CRP (R2 = 0.52, p < 0.0001). PaO2x alone was an even stronger predictor of CRP (R2 = 0.62, p < 0.0001). CONCLUSIONS: These findings indicate that physiological determinants of tissue oxygen availability are independently associated with CRP blood levels. Thus, improvement of tissue oxygen availability is a central therapeutic option to modulate the severity of systemic inflammatory processes in patients with COPD.

Análise das capacidades físicas em crianças dos sete aos dez anos de idade / Analysis of physical performance in children of seven to ten years old

Capacidade física é o termo utilizado para agrupar as capacidades força, velocidade, resistência, flexibilidade e coordenação. O desempenho físico de crianças é preocupação permanente entre os especialistas da área da saúde. Esse interesse justifica-se já que a atividade física desempenha importante papel na prevenção de doenças e melhoria da capacidade funcional. O objetivo do presente estudo foi analisar as capacidades físicas em crianças de ambos os sexos. Após consentimento por escrito dos pais, participaram do estudo 232 crianças de ambos os sexos entre as idades de sete e 10 anos. A capacidade física foi avaliada utilizando-se os testes de sentar e alcançar, resistência abdominal, salto horizontal e corrida de 30 metros. Foi utilizado ANOVA two way e post hoc de Tukey para comparação das variáveis entre as idades e o sexo. O nível de significância foi de 5%. A flexibilidade não foi modificada pela idade e sexo. O salto horizontal e o número de abdominais foram maiores nos meninos comparados às meninas e nas idades de 10, nove e oito anos comparados a idade de sete anos. O tempo para percorrer 30 m foi menor nos meninos comparado às meninas, sendo que a idade de 10 anos apresentou valores menores comparado as demais idades e as idades de nove e oito anos demonstraram menores valores comparado a idade de sete anos. De modo geral, os meninos apresentam melhor desempenho físico comparado às meninas na faixa etária avaliada. A idade de sete anos parece representar um período de transição no desempenho físico.

Physical performance is the term used to group strength, speed, endurance, flexibility and coordination capacities. The physical performance in the children is concern among experts in the field of health. This interest justified because physical activity can prevent illness and increase functional capacity. The aim of present study was assessment physical capacity in children of both sex, boys and girls. After consent of parents, concerns of study 232 children among seven and 10 years-old of both sexes. The performance motor was assessment using sit-and-reach, horizontal jump, abdominal endurance and 30 meters tests run. ANOVA Two-way and Tukey post hoc was used to compared variables among sex and ages. The significant level was 5%. Flexibility did not differ among ages and sex. The horizontal jump distance and abdominals number were higher in male group compared to the female group and eight, nine and 10 years-old were higher compared to seven years-old. The abdominals number was higher in male group compared to female group and eight, nine and 10 years-old are higher compared to seven years-old. The time to going 30 meters was small in the male group compared to female group and running time was small in the 10 years-old compared to other ages and the nine and eight years-old was small than seven years-old. In general, the boys presented better performance than girls in the ages assessment. The age seven years-old apparent represented a period of transition in the physical performance.

Distribuição regional do suor durante exercício progressivo até a fadiga / Sweat regional distribution during progressive exercise until fatigue

A partir da hipótese evolutiva de que a cabeça humana precisa ser resfriada de forma especial, o objetivo do presente estudo foi verificar se a sudorese seria maior na testa do que nas demais regiões do corpo durante o exercício progressivo até a fadiga (EPF). Em 17 voluntários (23 ± 2 anos, 76,93 ± 7,74 kg, 179 ± 7 cm e 1,9 ± 0,1 m²) foram medidos a taxa de sudorese local (TSlocal), o número de glândulas de suor ativas (GSA) e taxa de suor por GSA (TSlocal.GSA-1) em oito regiões do corpo (testa, costas, peito, braço, antebraço, mão, coxa e perna) durante o EPF em cicloergômetro. A TSlocal da testa foi maior que todas as outras regiões e a TSlocal do peito foi maior apenas que a da coxa. O número de GSA da testa foi maior do que em todas as outras regiões, e a GSA da mão foi maior que do peito, braço, coxa e perna. A TSlocal.GSA-1 da testa foi maior do que as do braço, antebraço, mão e coxa, e a TSlocal.GSA-1 das costas e do peito foram maiores que do antebraço e mão. A produção de suor da parte superior do corpo (testa, costas, peito, braço, antebraço, mão) foi maior que a inferior (coxa e perna). Concluiu-se que o EPF desencadeou um padrão de produção de suor maior na cabeça que pode estar relacionado à maior convecção nas regiões mais altas do corpo.

Considering the hypothesis of human selective brain cooling during exercise should depend on greater sweating mechanism in the forehead. The purpose of this study was verify variations of sweat production between body regions during progressive exercise until fatigue (PEF). Seventeen subjects (23 ± 2 years old, 76.93 ± 7.74 kg, 179 ± 7 cm and 1.9 ± 0.1 m²) volunteered for this study. Local sweat rate (STlocal), number of active sweat glands (ASG) and sweat rate for ASG (STlocal.ASG-1) in eight body regions (forehead, back, chest, arm, forearm, hand, leg and calf) were measured during PEF in cyclergometer. The STlocal of the forehead was higher than in all others regions and the chest STlocal was higher only than the leg. The number of ASG in the forehead was greater than in all other regions, and the ASG of the hand was higher than those of the chest, arm, leg and calf. The STlocal.ASG-1 of the forehead was higher than the arm, forearm, hand and leg, and the STlocal. ASG-1 of the chest and back were higher than the forearm and hand. The sweat production of the upper body (forehead, back, chest, arm, forearm and hand) was bigger than the lower body (leg and calf). In conclusion, the PEF promoted a sweating pattern in body regions that can be related to the higher convection present in the upper regions of the body.