Locomotion as a Powerful Model to Study Integrative Physiology: Efficiency, Economy, and Power Relationship

Locomotion is the most common form of movement in nature. Its study allows analysis of interactions between muscle functions (motor) and lever system arrangements (transmission), thereby facilitating performance analysis of various body organs and systems. Thus, it is a powerful model to study various aspects of integrative physiology. The results of this model can be applied in understanding body functions and design principles as performance outputs of interest for medical and biological sciences. The overall efficiency (effoverall) during locomotion is an example of an integrative parameter, which results from the ratio between mechanical output and metabolic input. Although the concepts of cost (i.e., metabolic expenditure relative to distance) and power (i.e., metabolic expenditure relative to time) are included in its calculation, the effoverall establishes peculiar relations with these variables. For a better approach to these aspects, in this study, we presented the physical-mathematical formulation of efficiency, as well as its conceptual definitions and applications. Furthermore, the concepts of efficiency, cost, and power are discussed from the biological and medical perspectives. Terrestrial locomotion is a powerful model to study integrative physiology in humans, because by analyzing the mechanical and metabolic determinants, we may verify the efficiency and economy relationship through locomotion type, and its characteristics and restrictions. Thus, it is possible to elaborate further on various improved intervention strategies, such as physical training, competition strategies, and ergogenic supplementation

Relações energéticas entre potência, eficiência e economia locomotora em pacientes com doença pulmonar obstrutiva crônica

Introdução: o estudo da energética locomotora permite conhecer fenômenos locomotores a partir de uma perspectiva integrativa e, dessa forma, conhecer suas características, determinantes, bem como, avaliar o efeito de intervenções. Objetivos: o presente estudo teve dois objetivos: analisar por meio de uma revisão narrativa o ―estado da arte‖ das relações entre economia, eficiência e potência em diferentes tipos de locomoções, sob efeito de diferentes restrições e desordens locomotoras (Artigo A); avaliar por meio de um ensaio clínico o efeito da Reabilitação Pulmonar (RP) nas relações entre potência e economia através de parâmetros energéticos locomotores e comparar esse efeito entre pacientes com Doença Pulmonar Obstrutiva Crônica (DPOC) submetidos ou não a redução de volume pulmonar por válvulas endobrônquicas (RVPVE) (Artigo B). Desenho Experimental: Revisão Narrativa e Ensaio Clínico Não Randomizado (ECNR). Local da Pesquisa: Hospital de Clínicas de Porto Alegre (HCPA) e Escola de Educação Física, Fisioterapia e Dança (ESEFID) da Universidade Federal do Rio Grande do Sul Porto Alegre, Rio Grande do Sul, Brasil. Métodos: para o Artigo A, foi realizada uma ampla revisão de literatura não permitindo restrições em relação ao período da publicação e utilizando critérios pessoais para sua escolha; para o Artigo B, 16 pacientes submetidos ou não a RVPVE foram avaliados antes e depois da RP. Desfechos do Artigo A: foram verificados resultados de custo metabólico ou economia, eficiência mecânica e potência e analisados suas relações a partir do tipo de locomoção realizada. Desfechos do Artigo B: Foram avaliados desfechos locomotores e energéticos em testes de caminhada realizados no plano: distância percorrida, velocidade no Teste de Caminhada de seis minutos (VelTC6), velocidade autosselecionada (VAS) e máxima (Vmáx) de caminhada, Índice de Realibilitaçao Locomotora (IRL); na inclinação: velocidade vertical de caminhada, potência mecânica vertical (Potmecvert); no cicloergômetro: eficiência mecânica (eff), Tempo limite (Tlim) e desfechos respiratórios em testes de função pulmonar. Procedimentos Estatísticos: para o Artigo B, os dados foram apresentados em ―model-based adjusted means‖ e foram analisados com o software Statistical Package for the Social Science (SPSS) v.22.0. Adotou-se um nível de significância de α = 0,05. Resultados: A RP aumentou o Tlim (3x), a potência nos desfechos locomotores (VelTC6: +7,5%; VAS: +11,0%; Vmáx: +11,3%; Potmecvert líquida: +14,1%; velocidade vertical: +12,1%;), energéticos (IRL: +11,1%; effisotime: +19,4%; efffinal: +10,2%) e diminuiu a dispneia (mMRC: -60%) (p < 0,05). Conclusão: pessoas com diferentes tipos de restrições locomotoras, dentre eles pacientes com DPOC, apresentam diminuição da economia de caminhada porque precisam caminhar em velocidades reduzidas. Intervenções apropriadas, especialmente aquelas que desenvolvem a produção de potência, permitem que essas pessoas consigam aumentar a velocidade de caminhada, diminuir seu custo energético e suportar níveis maiores de estresse fisiológico. É possível que os pacientes submetidos a RVPVE sofreram adaptações antes da RP, o que acabou limitando um possível efeito adicional.Introduction: Locomotors energy studies allow us to know the phenomena from an integrative perspective and, in this way, to know its characteristics, determinants, as well as to evaluate the effect of interventions. Objectives: The present study had two objectives: to analyze by a narrative review the state of the art of the relations between economy, efficiency and power in different types of locomotions, under the effect of different restrictions and locomotor disorders (study A); to evaluate by a clinical trial the effect of Pulmonary Rehabilitation (PR) on relations between power and economy through locomotor energy parameters and to compare this effect among patients with Chronic Obstructive Pulmonary Disease (COPD) submitted or not to bronchoscopic lung volume reduction (BLVR) (study B). Experimental Design: Narrative Review and Non-Randomized Clinical Trial (NRCT). Research Location: Hospital de Clínicas de Porto Alegre (HCPA) and Escola de Educação Física, Fisioterapia e Dança (ESEFID) of Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil. Methods: For study A, a broad literature review was carried out, without restrictions regarding the period of publication and using personal criteria for its choice; for study B, 16 patients submitted or not to BLVR were evaluated before and after PR. Outcomes of study A: Results of metabolic cost or economy, mechanical efficiency and power were verified and their relationships based on type of locomotion performed were analyzed. Outcomes of study B: Locomotors and energetics outcomes were evaluated in walking tests performed on level: distance traveled, six minutes walking test speed (6MWTS), self-selected walking speed (SSWS), maximal walking speed (MWS), Locomotor Rehabilitation Index (LRI); inclination: vertical walking speed, vertical mechanical power (netPowup); cycle ergometer: mechanical efficiency (eff), time limit (Tlim) and respiratory outcomes in pulmonary function tests. Statistical Procedures: For study B, the data were presented in model-based adjusted means and were analyzed with the Statistical Package for Social Science (SPSS) v.22.0 software. A significance level of α = 0.05 was adopted. Results: PR increased Tlim (3x), the power in locomotor (6MWTS: + 7,5%, SSWS: + 11.0%, MWS: + 11.3%, netPowup: +14.1%, vertical velocity: +12.1%), and energetic outcomes (LRI: + 11.1%, effisotime: + 19.4%, effend: + 10.2%) and decreased dyspnea (mMRC: -60%) (p <0.05). Conclusion: People with different types of locomotor restraints, as well as patients with COPD, present a decrease in walking economy because they need to walk at reduced speeds. Appropriate interventions, especially those that develop power production, allow to increase walking speed, decreasing their energy cost, and to resist higher levels of physiological stress. It‘s possible that patients submitted to BLVR had adaptations before PR, which eventually limited a possible additional effect

The Effects of Strength Training in Hydrogymnastics for Middle-Age Women

This study analyzed the effects of different strength training protocols carried out in hydrogymnastics workouts on the maximal strength of the shoulder horizontal flexors (SHF), shoulder horizontal extensors (SHE), and hip extensors (HE) muscles. Fifty-two women (ages 50.4 ± 14.15 years) were divided into two groups: hydrogymnastics with strength training without resistive equipment (HS) and hydrogymnastics with strength training using resistive equipment (HSE). The training lasted 12 weeks (2x a week) and the intensity was selected using Borg’s rating of perceived exertion scale for both groups. After 12 weeks of training, both groups showed an increase in maximal strength of all muscles analyzed for HS (SHF: 13.68 ± 3.20kg vs. 16.02 ± 2.57kg; SHE: 17.20 ± 6.54kg vs. 21.14 ± 2.44kg; HE: 22.79 ± 6.98kg vs. 32.27 ± 6.57kg) and for HSE (SHF: 13.52 ± 3.53 vs. 16.02 ± 4.13kg; SHE: 18.23 ± 3.43 vs. 20.02 ± 4.32kg; HE: 24.79 ± 6.91 vs. 33.29 ± 5.71). There were no differences between training groups. These results indicated that the hydrodynamic strength training exercises may increase the maximal strength of middle-age women, independent of the type of resistive equipment

Physiologic and Kinematical Effects of Water Run Training on Running Performance

The purpose of this study was to analyze whether trained competitive runners could maintain running kinematics, cardiorespiratory performance (VO2peak, ventilatory threshold, running economy) and on-land running performance by replacing 30% of conventional training with water run training during 8 weeks. Eighteen runners were divided in two groups: on-land run (OLR Group) and deep water run (DWR Group). The DWR Group replaced 30% of training volume on land with DWR and the OLR group trained only on land (both groups undertaken workouts 6-7 d.wk-1 for a total of 52 sessions). No significant intra- or intergroup differences were observed for VO2peak in the DWR Group and OLR Group. Similarly, ventilatory threshold second was unaltered in the DWR Group and OLR Group. Regarding running economy (at 14 km.h-1) also, no intra- or intergroup differences were found in the DWR Group (pre = 43.4 ± 5.0, post = 42.6 ± 3.85 ml.kg-1.min-1) and OLR Group (pre = 43.9 ± 2.5, post = 42.6 ± 2.6 ml.kg-1.min-1). Kinematic responses were similar within and between groups. Water running may serve as an effective supplementary training over a period of 8 weeks up to 30% of land training volume for competitive runners

Factors infuencing self‑selected walking speed in fbrotic interstitial lung disease

This study aimed to investigate the walking economy and possible factors infuencing self-selected walking speed (SSWS) in patients with fbrotic interstitial lung disease (ILD) compared to controls. In this study, 10 patients with ILD (mean age: 63.8 ± 9.2 years, forced expiratory volume in the frst second: 56 ± 7% of predicted) and 10 healthy controls underwent resting pulmonary function tests, cardiopulmonary exercise, and submaximal treadmill walking tests at diferent speeds. The walking economy was assessed by calculating the cost-of-transport (CoT). Dynamic stability was assessed by stride-to-stride fuctuations using video recordings. Patients with ILD showed reduced peak oxygen uptake with a tachypneic breathing pattern and signifcant oxygen desaturation during exercise. The CoT did not difer between the groups (p= 0.680), but dyspnea and SpO₂ were higher and lower, respectively, in patients with ILD at the same relative speeds. SSWS was reduced in ILD patients (2.6 ± 0.9 vs. 4.2 ± 0.4 km h⁻¹ p = 0.001) and did not correspond to the energetically optimal walking speed. Dynamic stability was signifcantly lower in patients with ILD than in healthy controls, mainly at lower speeds. Patients with ILD presented a similar cost of transport compared to healthy controls; however, they chose lower SSWS despite higher walking energy expenditure. Although walking stability and dyspnea were negatively afected, these factors were not associated with the slower walking speed chosen by individuals with ILD

INFLUENCE OF DEEP WATER RUN TRAINING SUPPLEMENT ON THE MAINTENANCE OF AEROBIC PERFORMANCE AND KINEMATICS OF MIDDLE-DISTANCE RUNNERS

The purpose of this study was to examine whether trained competitive runners could maintain on-land running performance and kinematics, using 8 wk of deep water run supplement training (30%) instead of just on-land training. Eight trained male runners (V02MAX: 53,3 ± 4.1 ml. Kg,1. min,1) were assigned to one of the two groups, on-land run just (R) or water run supplement (WR). Following 8 wk of workouts, no significant intragroup or intergroup differences were observed for treadmill V02MAX, running economy, horizontal velocity, stride length, stride rate, time of support, time of flight and segmental body positions. It was concluded that deep water running may serve as an effective training supplement to land-based running for the maintenance of aerobic performance and running kinematics for up 8 wk in trained middle-distance runners

RELAÇÃO ENTRE O CONDICIONAMENTO FÍSICO E A IDADE NO DESEMPENHO DE EQUIPES DE CORRIDA DE AVENTURA

O objetivo deste estudo foi correlacionar valores de consumo máximo deoxigênio (VO2máx) e variáveis avaliadas no segundo limiar ventilatório (2ºLV) de equipesde Corrida de Aventura. Seis equipes realizaram teste progressivo em esteira paradeterminação do VO2máx e do 2ºLV. Não foram encontradas diferenças significativas entreas médias das equipes e sua correlação com o desempenho foi baixa. Bons coeficientesforam encontrados entre idade e desempenho para navegadores (r =-0,77) e mulheres(r = -0,90; p&lt;0,05). Apesar do condicionamento físico ser requisito ao esporte, a experiênciados navegadores e da mulher pode ter contribuído para o desempenho das equipes

Objetividade e fidedignidade do sistema de digitalização manual para o movimento de corrida

É fundamental na análise técnica da pesquisa esportiva o conhecimento das diversas fontes de variabilidade, especialmente avaliando as diferenças intra e inter-avaliadores. A proposta deste estudo foi examinar a objetividade e fidedignidade do processo de digitalização manual em uma seqüência de imagens de corrida entre três avaliadores e entre três digitalizações de um avaliador, e analisar o efeito da filtragem dos dados sobre a variabilidade dos dados (desvio-padrão). Todos os testes de Correlação Intra-Classe apresentaram altos coeficientes de correlação. 0 processo de digitalização manual é objetivo e fidedigno no movimento de corrida.Un understanding ofthe different variation sources in experimental sport research is fundamental to technical analysis, especially when comparing the Intra- and inter-evaluator differences. The purpose of thís study was to examine the objectivity and reliability of manual digitisation process in the analysed sequence of running among three evaluators and among three digitisations of the same evaluator, and analyse the effect of smoothing about the variability (standard deviation). Ali Intra-Class Correlations showed high correlation s coefficient This demonstrate that the manual digitisation process is objective and reliable for running movement

OBJETIVIDADE E FIDEDIGNIDADE DO SISTEMA DE DIGITALIZAÇÃO MANUAL PARA O MOVIMENTO DE CORRIDA

É fundamental na análise técnica da pesquisa esportiva o conhecimento das diversas fontes de variabilidade, especialmente avaliando as diferenças intra e inter-avaliadores. A proposta deste estudo foi examinar a objetividade e fidedignidade do processo de digitalização manual em uma seqüência de imagens de corrida entre três avaliadores e entre três digitalizações de um avaliador, e analisar o efeito da filtragem dos dados sobre a variabilidade dos dados (desvio-padrão). Todos os testes de Correlação Intra-Classe apresentaram altos coeficientes de correlação. 0 processo de digitalização manual éobjetivo e fidedigno no movimento de corrida.ABSTRACTUn understanding ofthe different variation sources in experimental sport research is fundamental to technical analysis, especially when comparing the Intra- and inter-evaluator differences. The purpose of thís study was to examine the objectivity and reliability of manual digitisation process in the analysed sequence of running among three evaluators and among three digitisations of the same evaluator, and analyse the effect of smoothing about the variability (standard deviation). Ali Intra-Class Correlations showed high correlation s coefficient This demonstrate that the manual digitisation process is objective and reliable for running movement