Foi objectivo desta dissertação comparar e caracterizar a resposta cardiorrespiratória, metabólica e biomecânica em nadadores de recreação versus competição. Fizeram parte do presente estudo 20 nadadores portugueses do sexo masculino (8 recreação e 12 de competição). Recorreu-se à aplicação de um teste incremental de 7 x 200-m Crol de modo a determinar diversas variáveis cardiorrespiratórias, metabólicas e biomecânicas. Para ser possível comparar os grupos à mesma intensidade de esforço, procedeu-se à relativização das variáveis seleccionadas à velocidade de nado das 4 mmol·l-1 de concentração de lactato. Para verificar a existência de diferenças significativas entre os dois grupos recorreu-se ao teste de Anova a um factor (nadador: recreação vs competição). Os nadadores de competição apresentaram uma velocidade às 4 mmol·l-1 (F(1,18)= 73,541, p= 0,001), um consumo máximo de oxigénio (F(1,18)= 13,152, p= 0,002), uma velocidade mínima de obtenção do consumo máximo de oxigénio (F(1,18)= 29,364, p= 0,001), um dispêndio energético total às 4 mmol·l-1 (F(1,18)= 11,717, p= 0,003), uma frequência gestual às 4 mmol·l-1 (F(1,18)= 45,584, p= 0,001), uma velocidade (F(1,18)=52,690, p= 0,001) e um índice de nado às 4 mmol·l-1 (F(1,18)=25,424, p= 0,001) significativamente superior aos nadadores de recreação. Não se verificaram diferenças significativas entre os grupos no pico de lactato após o esforço (F(1,18)= 1,832, p= 0,193); no custo energético às 4 mmol·l-1 (F(1,18)=1,50, p= 0,703); na distância de ciclo às 4 mmol·l-1 (F(1,18)= 0,044, p= 0,836),e na eficiência propulsiva às 4 mmol·l-1 (F(1,18)= 0,315, p= 0,582). Os nadadores de competição apresentaram valores superiores aos de recreação em quase todas as variáveis estudadas. Essa superioridade permite-lhes obter melhores performances quando comparados com os nadadores de recreação pela presença de um perfil fisiológico mais elevado. The aim of the present dissertation was to compare and characterize the cardiorespiratory, metabolic and biomechanical response between recreation swimmers and competitive swimmers. Twenty Portuguese male swimmers (eight masters and twelve elite) were evaluated. An incremental set of 7 x 200 m swims Crawl was applied to assess the cardio-respiratory, metabolic and biomechanical data. All energetic and biomechanical variables were related at velocity of the 4 mmol·l-1 to of lactate concentrations to compare all swimmers at the same intensity. Differences between both groups were testes with one away Anova (swimmer: recreation versus competition). The competitive swimmers presented a velocity at the 4 mmol·l-1 (F(1,18)= 73,541, p= 0,001), maximal oxygen consumption (F(1,18)= 13,152, p= 0,002), minimum swimming velocity where the maximal oxygen consumption is reached (F(1,18)= 29,364, p= 0,001), maximal total metabolic power at velocity at the 4 mmol·l-1 (F(1,18)= 11,717, p= 0,003), stroke frequency at velocity at the 4 mmol·l-1 (F(1,18)= 45,584, p= 0,001), mean swimming velocity (F(1,18)= 52,690, p= 0,001) and stroke index at velocity at the 4 mmol·l-1 (F(1,18)= 25,424, p= 0,001) significantly higher than recreational swimmers. There were no significant differences between the groups in the highest value of peak lactic acid after exercise (F(1,18)= 1,832, p= 0,193); energy cost at velocity at the 4 mmol·l-1 (F(1,18)= 1,50, p= 0,703); stroke length at velocity at the 4 mmol·l-1 (F(1,18)= 0,044, p= 0,836), and propelling efficiency at velocity at the 4 mmol·l-1 (F(1,18)= 0,315, p= 0,582). The competitive swimmers presented higher values than recreational swimmers in almost all variables assessed. This superiority allows them to achieve better performances when compared to recreational swimmers by the presence of a physiological profile more accurate.

The aim was to assess the interaction between kinematics and neuromuscular responses of subjects performing the rowing exercise with barbell in group fitness classes with different external loads and cadences. Fifteen male subjects performed nine sets of nine repetitions of the selected exercise. Sets were composed by a pair wise combination of different external loads (5, 10 and 20 [kg]) and cadences (1, 2 and 4 musical beats) in a randomized order. Kinematical data was collected with an electrogoniometer and it was assessed the: (i) absolute duration of each exercise repetition; (ii) minimum relative angle between the arm and forearm during the flexion action. Neuromuscular data was collected with superficial electromyography and it was computed the EMG amplitude (aEMG), the EMG room mean square (RMS) and the activation time of five muscles from the arm and trunk. Increasing cadence decreased the absolute duration of the exercise cycle. There was no significant interaction between the joint angle and the external load nor the cadence. Increases in the external load and in the cadence imposed a RMS increase as well. It was also verified a significant interaction among the aEMG and the external load in the four muscle groups.

Competition in masters swimming is getting tougher. Athletes are dedicating more time and effort to excel in masters competitions than they use to. Research question: What are the factors associated with masters and elite swimmers performance? Type of study: A cohort group comparison (young master versus elite swimmers) and a correlational study (association between selected variables and performance) were conducted. Purpose: The aim was to identify the energetics, kinematics and efficiency variables associated with young masters (former elite) and elite swimmers performance as well as compare it between both cohort groups. Methods: Twenty male swimmers (masters: N=8, 29.75±3.80-y; elite: N=12, 20.41±3.20-yld) performed a 7x200m freestyle swim. The performance (200m freestyle at official competition), velocity at which the 4 mmol.l-1 of blood lactate was assessed (V4), peak blood lactate concentrations (Lapeak), peak oxygen up-take (VO2peak), minimum velocity to elicited VO2peak (vVO2peak), total energy expenditure (Ėtot), stroke frequency (SF), stroke length (SL), mean swimming velocity (v), energy cost (C), stroke index (SI) and propelling efficiency (p) to check whether this was achieved. Results: Elite swimmers presented a better performance. V4, VO2peak, vVO2peak, Ėtot , SF, v and SI were significantly higher in elite swimmers. For both groups performance was associated with the V4, vVO2peak and v. In addition, elite swimmers’ performance was impaired with regard to the Lapeak. Conclusions: Young masters swimmers presented impairment in performance related to a decrease in the energetics profile and biomechanical behaviour. Nevertheless, their previous background as elite swimmers allowed them to maintain high swimming efficiency.

O objectivo do estudo foi desenvolver e validar equações para estimar a área de secção transversa do tronco (ASTT), em ambos os sexos, de acordo com o nível competitivo, que habitualmente são usadas para avaliar o arrasto hidrodinâmico. Para o sexo feminino, na condição de experts, foi utilizado um grupo de 33 sujeitos para estimar a equação e um grupo de 38 sujeitos para validar a equação, na condição de não experts foi utilizado um grupo de 23 sujeitos para estimar a equação e um grupo de 18 sujeitos para validar a mesma. No caso do sexo masculino, na condição de experts, foi utilizado um grupo de 28 sujeitos para estimar a equação e um grupo de 32 sujeitos para a validar, na condição de não experts, foi utilizado um grupo de 48 sujeitos para estimar a equação e um grupo de 44 sujeitos para validar a equação. Os sujeitos foram fotografados (DSC-T7, Sony, Tóquio, Japão) num plano superior transversal, no meio terrestre, simulando a posição hidrodinâmica. A ASTT foi medida através da foto digital do sujeito com um software específico (Universal Desktop Ruler, v3.3.3268, AVPSoft, E.U.A.). Foram ainda medidas as variáveis antropométricas massa corporal (SECA, 884, Hamburgo, Alemanha), a estatura (SECA, 242, Hamburgo, Alemanha), os diâmetros bi-acromial (DBC) e tóraco-sagital (DTS) com um clip antropométrico (Campbell, 20, RossCraft, Canadá), assim como, o perímetro peitoral (PP) com fita métrica (RossCraft, Canadá). Para sexo feminino experts ASTT=16,498*DTS+10,875*PP-504,705 (R2=0,28; Ra=0,24; p<0,01). Para sexo feminino não experts ASTT=14,836*PP-26,825*DTS-33,149 (R2=0,28; Ra=0,21; p<0,01). Para sexo masculino experts ASTT=19,216*DTS+10,505*PP-575,496 (R2=0,33; Ra=0,27; p<0,01). Para sexo masculino não experts ASTT=30,453*DTS+5,030*PP-371,404 (R2=0,48; Ra=0,45; p<0,01). Em todas as condições, por sexo e nível competitivo, não se verificaram diferenças estatisticamente significativas entre a média da ASTT medida e da estimada. Os coeficientes de determinação, calculados através da análise de regressão linear, entre a ASTT medida e estimada foram moderados. Para todas as condições, por sexo e nível competitivo, mais de 80% dos plots, na análise de Bland-Altman, encontram-se dentro dos 95% do intervalo de confiança.

A higher underwater gliding distance seems to be associated to a decrease of the passive drag (Marinho et aI., 2010). But it also can be related to other variables 5uch as muscle power of the lower limbs, while pushing the forehead wall. At least one paper reported that during tums, muscle power from lower limbs is a determinant factor (Potdevin et al. 2011). The aim of this study was to develop a structural equation model for underwater gliding distance based on these selected variables.

The aim of this study was to compute and validate trunk transverse surface area (TTSA) estimation equations to be used assessing the swimmer’s drag force according to competitive level by gender. One group of 130 swimmers (54 females and 76 males) was used to compute the TTSA estimation equations and another group of 132 swimmers (56 females and 76 males) were used for its validations. Swimmers were photographed in the transverse plane from above, on land, in the upright and hydrodynamic position. The TTSA was measured from the swimmer’s photo with specific software. It was also measured the height, body mass, biacromial diameter, chest sagital diameter (CSD) and the chest perimeter (CP). With the first group of swimmers it was computed the TTSA estimation equations based on stepwise multiple regression models from the selected anthropometrical variables. The TTSA prediction equations were significant and with a prediction level qualitatively considered as moderate. All equations included only the CP and the CSD in the final models. In all prediction models there were no significant differences between assessed and estimated mean TTSA. Coefficients of determination for the linear regression models between assessed and estimated TTSA were moderate and significant. More than 80% of the plots were within the 95% interval confidence for the Bland-Altman analysis in both genders. So, TTSA estimation equations that are easy to be computed by coached and researchers were developed. All equations accomplished the validation criteria adopted.