Rafael Reimann Baptista

A comparison between the 2010 and 2005 basic life support guidelines during simulated hypogravity and microgravity

BackgroundCurrent 2010 terrestrial (1Gz) CPR guidelines have been advocated by space agencies for hypogravity and microgravity environments, but may not be feasible. The aims of this study were to (1) evaluate rescuer performance over 1.5 min of external chest compressions (ECCs) during simulated Martian hypogravity (0.38Gz) and microgravity (μG) in relation to 1Gz and rest baseline and (2) compare the physiological costs of conducting ECCs in accordance with the 2010 and 2005 CPR guidelines.MethodsThirty healthy male volunteers, ranging from 17 to 30 years, performed four sets of 30 ECCs for 1.5 min using the 2010 and 2005 ECC guidelines during 1Gz, 0.38Gz and μG simulations (Evetts-Russomano (ER) method), achieved by the use of a body suspension device. ECC depth and rate, range of elbow flexion, post-ECC heart rate (HR), minute ventilation (VE), peak oxygen consumption (VO2peak) and rate of perceived exertion (RPE) were measured.ResultsAll volunteers completed the study. Mean ECC rate was achieved for all gravitational conditions, but true depth during simulated microgravity was not sufficient for the 2005 (28.5 ± 7.0 mm) and 2010 (32.9 ± 8.7 mm) guidelines, even with a mean range of elbow flexion of 15°. HR, VE and VO2peak increased to an average of 136 ± 22 bpm, 37.5 ± 10.3 L·min−1, 20.5 ± 7.6 mL·kg−1·min−1 for 0.38Gz and 161 ± 19 bpm, 58.1 ± 15.0 L·min−1, 24.1 ± 5.6 mL·kg−1·min−1 for μG from a baseline of 84 ± 15 bpm, 11.4 ± 5.9 L·min−1, 3.2 ± 1.1 mL·kg−1·min-1, respectively. RPE was the only variable to increase with the 2010 guidelines.ConclusionNo additional physiological cost using the 2010 basic life support (BLS) guidelines was needed for healthy males performing ECCs for 1.5 min, independent of gravitational environment. This cost, however, increased for each condition tested when the two guidelines were compared. Effective ECCs were not achievable for both guidelines in simulated μG using the ER BLS method. This suggests that future implementation of an ER BLS in a simulated μG instruction programme as well as upper arm strength training is required to perform effective BLS in space.

Limiar de lactato em remadores: comparação entre dois métodos de determinação

The objective of this study was to compare the 4 mM (AT4) and Dmax methods for lactate threshold determination. Ten male (23.7 ± 3.33 years) and four female rowers (18 ± 0.81 years), divided into three groups: heavy weight (n = 6), light weight (n = 4), and female (n = 4), (87.23 ± 6.10, 73.22 ± 2.38, 63.27 ± 8.86 kg and 187.66 ± 1.63, 183 ± 6.05, 172 ± 5.16 cm respectively), were submitted to a maximal rowing ergometry, with initial workload of 130 to 150 W and increases of 30 to 50 W every 5 minutes, with 1 minute pause for blood sampling. Power output, heart rate and lactate values were determined at every workload and used for the determination of the thresholds according to both methods. Lactate concentration, power output and heart rate, identified by Dmax method were compared with the AT4 method in the heavy weight (3.01 ± 0.73 vs. 4 mM, 268.33 ± 29.44 vs. 312 ± 44.02 W and 164 ± 4.81 vs. 174 ± 10.09 bpm), light weight (2.51 ± 0.53 vs. 4 mM, 232.50 ± 15.00 vs. 277.50 ± 25.98 W and 160 ± 8.47 vs. 177 ± 3.79 bpm) and female (3.21 ± 0.41 vs. 4 mM, 160 ± 14.41 vs. 167.50 ± 15.00 W and 175 ± 20.42 vs. 185 ± 12.12 bpm) groups through the paired Student t-test, being significantly lower (p < 0.05) when the method Dmax was used. The results suggest that the AT4 method overestimates the variables analyzed in the lactate threshold when compared with the Dmax method.

Effects of an Educational Intervention of Physical Activity for Children and Adolescents With Cystic Fibrosis: A Randomized Controlled Trial

BACKGROUND: Regular aerobic exercise in patients with cystic fibrosis (CF) improves aerobic conditioning and delays disease progression, resulting in better quality of life. The purpose of this study was to evaluate the effect of an aerobic exercise program based on verbal and written guidelines on maximum exercise capacity using a cardiopulmonary exercise test, quality of life, and the self-reported aerobic exercise practice of children and adolescents with CF. METHODS: This randomized controlled trial followed guidelines for physical exercise in a CF center. Subjects were assigned to 2 groups: intervention (group 1), with 17 subjects; and control (group 2), also with 17 subjects. Data were collected from October 2010 to October 2011, and the study population comprised 7–20-y-old children and adolescents with CF. The intervention consisted of handing out a manual with guidelines for aerobic physical exercises and reinforcing recommendations in telephone calls every 2 weeks. RESULTS: Thirty-four subjects were included in the study, 20 of whom were boys (58.5%). The groups were similar at baseline. In group 1, 6 subjects (35.2%) reported practicing physical exercises regularly. The mean age was 13.4 ± 2.8 y, the mean percent-of-predicted FEV1 was 95.5 ± 17.9%, and the mean peak oxygen uptake (V̇O2) relative to body mass was 34.9 ± 9.0 mL/kg/min. In group 2, 4 subjects (23.5%) reported practicing physical exercises regularly. The mean age was 12.7 ± 3.3 y, the mean percent-of-predicted FEV1 was 100.1 ± 21.2%, and the mean peak V̇O2 was 33.2 ± 8.2 mL/kg/min. In group 1, there was a significant increase in physical exercise practice as reported by subjects after 3 months of intervention compared with group 2 (P = .01). No statistically significant differences were found for the other variables. CONCLUSIONS: Verbal and written guidelines for aerobic exercise, together with supervision over the telephone, had a positive impact on the self-reported regular physical exercise practice of children and adolescents. However, no improvement was found in lung function and maximum exercise capacity or domains of the quality of life questionnaire.

Arquitetura muscular e envelhecimento: adaptação funcional e aspectos clínicos; revisão da literatura

Ageing is associated to a progressive decline in muscle mass - a phenomenon known as sarcopenia - which directly affects muscle architecture and force production capacity. The purpose of this study was to review current literature on the effects of aging on muscle architecture, as well as review evidences on the effects of resistance training programs onto morphological properties of skeletal muscles, also discussing clinical implications of functional adaptation among the elderly. Forty-two articles, published between 1993 and 2008, were selected from Pubmed, Science Direct and Scopus databases, by using the key words aging, older adults, elderly, muscle architecture, strength training, and resistance training. The reviewed studies support the idea that there are differences in the architecture of elderly affected by sarcopenia when compared to healthy young adults. Evidences seem to be unanimous as to reduction in skeletal muscle volume, physiological cross sectional area and pennation angle due to aging. Aging also leads to a reduction in fascicular length and muscle width, which determines a reduction in anatomical cross-sectional area. Strength training programs have been used as a therapeutic technique in order to postpone or even revert aging effects on elderly skeletal muscle.

Maturity Status Does Not Exert Effects on Aerobic Fitness in Soccer Players After Appropriate Normalization for Body Size.

The present study investigated the effects of pubertal status on peak oxygen uptake (VO2peak), respiratory compensation point (RCP), and ventilatory threshold (VT) in young soccer players using different body size descriptors. Seventy-nine soccer players (14 prepubescent, 38 pubescent and 27 postpubescent) participated in this study. A maximal exercise test was performed to determine the VO2peak, RCP, and VT. Ultrasonography was used to measure lower limb muscle volume (LLMV). LLMV (mL-b) was rated as the most effective body size descriptor to normalize VO2peak (mLO2·mL-0.43·min-1), RCP (mLO2·mL-0.48·min-1), and VT (mLO2·mL- 0.40·min-1). The values of VO2peak, RCP, and VT relative to allometric exponents derived by LLMV were similar among groups (p > .05; 0.025 < η2 < 0.059) when the effect of chronological age was controlled. Allometric VO2peak, RCP, and VT values were: 100.1 ± 7.9, 107.5 ± 9.6, and 108.0 ± 10.3 mLO2.mL-0.43·min-1; 51.8 ± 5.3, 54.8 ± 4.7, and 57.3 ± 5.8 mLO2·mL-0.48·min-1; and 75.7 ± 7.1, 79.4 ± 7.0, and 80.9 ± 8.3 mLO2·mL- 0.40·min-1 for prepubertal, pubertal, and postpubertal groups, respectively. Maturity status showed no positive effect on VO2peak, RCP, and VT when the data were properly normalized by LLMV in young soccer players. Allometric normalization using muscle volume as a body size descriptor should be used to compare aerobic fitness between soccer players heterogeneous in chronological age, maturity status, and body size.

Three methods of manual external chest compressions during microgravity simulation.

INTRODUCTION Cardiopulmonary resuscitation (CPR) in microgravity is challenging. There are three single-person CPR techniques that can be performed in microgravity: the Evetts-Russomano (ER), Handstand (HS), and Reverse Bear Hug (RBH). All three methods have been evaluated in parabolic flights, but only the ER method has been shown to be effective in prolonged microgravity simulation. All three methods of CPR have yet to be evaluated using the current 2010 guidelines. METHODS There were 23 male subjects who were recruited to perform simulated terrestrial CPR (+1 G(z)) and the three microgravity CPR methods for four sets of external chest compressions (ECC). To simulate microgravity, the subjects used a body suspension device (BSD) and trolley system. True depth (D(T)), ECC rate, and oxygen consumption (Vo2) were measured. RESULTS The mean (+/- SD) D(T) for the ER (37.4 +/- 1.5 mm) and RBH methods (23.9 +/- 1.4 mm) were significantly lower than +1 G(z) CPR. However, both methods attained an ECC rate that met the guidelines (105.6 +/- 0.8; 101.3 +/- 1.5 compressions/min). The HS method achieved a superior D(T) (49.3 +/- 1.2 mm), but a poor ECC rate (91.9 +/- 2.2 compressions/min). Vo2 for ER and HS was higher than +1 Gz; however, the RBH was not. CONCLUSION All three methods have merit in performing ECC in simulated microgravity; the ER and RBH have adequate ECC rates, and the HS method has adequate D(T). However, all methods failed to meet all criteria for the 2010 guidelines. Further research to evaluate the most effective method of CPR in microgravity is needed.

Comparative study of anthropometric and body composition variables, and functionality between elderly that perform regular or irregular physical activity

Introducao: o impacto da atividade fisica regular e/ou irregular na composicao corporal, massa e forca muscular e funcionalidade em idosos e ainda pouco estudado. Objetivo: comparar variaveis antropometricas, espessura muscular e de gordura, mobilidade e forca de preensao palmar de membros inferiores entre idosos regular e irregularmente ativos classificados pelo International Phisical Activity Questionnnaire. Metodo: estudo transversal com 75 idosos (14 homens e 61 mulheres) que praticavam atividade fisica regular (AFR=10) ou irregular (AFI=65). Variaveis antropometricas (indice de massa corporal, circunferencias e dobras cutâneas), espessura muscular e de gordura (triceps braquial, vasto lateral e gastrocnemico medial [ultrassom]), forca de preensao palmar (dinamometro Crown), forca de membros inferiores (teste de senta e levanta) e mobilidade foram coletadas da amostra de idosos. A atividade fisica foi avaliada atraves do International Phisical Activity Questionnnaire. Resultados: nao foram encontradas diferencas significativas nas variaveis antropometricas, espessura muscular e de gordura e forca entre os dois grupos (p>0,05). No entanto, no grupo de idosos que praticavam atividade fisica irregular, foi obtido melhor desempenho no teste de mobilidade do que nos idosos que praticavam atividade fisica regular (p<0,008). Esse resultado foi independente de sexo e idade (p=0,017). Conclusao: o estudo nao encontrou diferencas significativas entre os idosos que praticam atividade fisica de forma regular ou irregular em relacao a composicao corporal e parâmetros de forca. Contudo, os resultados sugerem que a pratica de atividade fisica irregular pode ajudar a mobilidade dos idosos e prevenir quedas.

Lactate threshold in rowers: comparison between two methods of determination

The objective of this study was to compare the 4 mM (AT4) and Dmax methods for lactate threshold determination. Ten male (23.7 ± 3.33 years) and four female rowers (18 ± 0.81 years), divided into three groups: heavy weight (n = 6), light weight (n = 4), and female (n = 4), (87.23 ± 6.10, 73.22 ± 2.38, 63.27 ± 8.86 kg and 187.66 ± 1.63, 183 ± 6.05, 172 ± 5.16 cm respectively), were submitted to a maximal rowing ergometry, with initial workload of 130 to 150 W and increases of 30 to 50 W every 5 minutes, with 1 minute pause for blood sampling. Power output, heart rate and lactate values were determined at every workload and used for the determination of the thresholds according to both methods. Lactate concentration, power output and heart rate, identified by Dmax method were compared with the AT4 method in the heavy weight (3.01 ± 0.73 vs. 4 mM, 268.33 ± 29.44 vs. 312 ± 44.02 W and 164 ± 4.81 vs. 174 ± 10.09 bpm), light weight (2.51 ± 0.53 vs. 4 mM, 232.50 ± 15.00 vs. 277.50 ± 25.98 W and 160 ± 8.47 vs. 177 ± 3.79 bpm) and female (3.21 ± 0.41 vs. 4 mM, 160 ± 14.41 vs. 167.50 ± 15.00 W and 175 ± 20.42 vs. 185 ± 12.12 bpm) groups through the paired Student t-test, being significantly lower (p < 0.05) when the method Dmax was used. The results suggest that the AT4 method overestimates the variables analyzed in the lactate threshold when compared with the Dmax method.

New Team at the Journal and Birth of the MicroG Network

Edition number 1, volume 5 of Aviation in Focus – Journal of Aeronautical Sciences, brings together three original articles, one review and an interview. This edition also marks a change in the Editorial Board of the publication, with Prof. Thais Russomano, (Microgravity Centre/School of Medicine, PUCRS) assuming the position of Editor and Prof. Rafael Reimann Baptista (Microgravity Centre/Faculty of Physical Education, PUCRS) acting as Executive Editor. The first article in this issue, entitled Analysis of financial impact resulting from option for aircraft noise reduction against operational optimization at Brasilia International Airport, performs an analysis of the financial impact on the air transport system from the adoption of longer aircraft taxiing routes, due to noise pollution. The second article, ANACpedia: aviation, presents the ANACpedia, a database made up of aviation industry vocabulary in the form of lists of terms, composed of two bilingual glossaries (English-Portuguese/Portuguese-English, Spanish-Portuguese/Portuguese-Spanish) and a list English acronyms. The third article, entitled Women in aviation: less posing, more action, aims to investigate the profile and media representation of female professionals in aviation. The fourth article, Leadership approaches in multi-cultural aviation environments, gives a detailed analysis through a literature review of leadership approaches in multi-cultural working environments within the aviation industry. The edition closes with an interview with researcher Agustín Folgueira, Professor of Neuroanatomy at the University of Buenos Aires. He is currently working as a doctor at the Belgrano II Base in Antarctica, in addition to developing a study related to the Mars 500 project. Editorial Open Access

Aspectos fisiológicos e biomecânicos da produção de força podem ser usados no controle do treinamento de remadores de elite

The sports science currently requires approaches that match the study of biomechanical and physiological aspects, for the correct understanding of the phenomena related to human performance. The aim of this study was to investigate the differences in biomechanical and physiological responses between different force-time curves in rowers. Fifteen rowers (23.6 ±5.4 yrs), were submitted to maximal rowing ergometer. The biomechanical (peak force, power and impulse) and physiological (VO2, VCO2, VE, RER MET, lactate and HR) responses were measured in the lactate threshold stage as well as in the maximal stage reached by the rowers. The rowers were classified in two groups according to the localization of the peak force in their force-time curves: peak force in the first half of the curve (stroke) or in the second half of the curve (bow). There are no significant differences between the parameters measured in the two groups at lactate threshold stage of the rowing ergometer. Twelve rowers presented finish accentuated force curve in the lactate threshold; however, five (41.7%) changed for a catch accentuated pattern, while seven (58.3%) kept the original force-time profile in the maximal stage of the rowing ergometer. The rowers with a finish accentuated profile showed higher power production (p<0.05). The results suggest that coaches interested in extending exercise time must seek a finish accentuated force-time profile. Catch accentuated rowers could be better adapted to faster boats.