7 research outputs found
Relação entre velocidade crítica, limiar anaeróbio, parâmetros associados ao VO2max, capacidade anaeróbia e custo de O2 submáximo
Get PDFThe purposes of the study were to compare and correlate the running velocities associated with the maximal oxygen consumption (Vmax), anaerobic threshold (LL), ventilatory threshold (LV), critical velocity (CV), anaerobic work capacity (AWC) and oxygen cost during sub-maximal exercise (C). METHODS: Eight male physically active subjects (20.8±1.6 years; 74.3±14.9 kg), performed the following tests: 1) 500m and 3km time trial (Vm500 and Vm3km); 2) Incremental test on treadmill for of LL, LV, VO2max and Vmax identification; 3) sustained running at Vmax (Tmax) and identification of the time to VO2max and time at VO2max. The CV and AWC were obtained from linear regression (distance x time on 500m and 3km test). The C was determined as a ratio between sub-maximal running velocity and its VO2. RESULTS: A high correlation was verified for Vm3km and Vmax (r=0.83), Vm3km and VC (r=0.98), Vm500 and VC (r=0.90), Vm500 and Vm3km (r=0.92), and between Vm500 and Time to VO2max (r=0.69). No differences were observed between LL and LV (178.7±20.0 e 180.7±21.8m.min –1) (p>0.05). Also a high correlation between LL and Vmax¬ (r=0.91), CV (r=0.96), and Vm3km (r=0.96) were verified. The AWC was negatively correlated to running economy for those with higher aerobic capacity. CONCLUSION: The CV, AWC, Vm500 an Vm3km can be used for exercise evaluation and training prescription. Due the correlation with the C, the AWC may be an indicative of mechanical inefficiency.Os objetivos do estudo foram analisar as relações existentes entre a velocidade de corrida associada ao VO2max (Vmax), tempo para obtenção do VO2max na Vmax, tempo no VO2max, limiar de lactato (LL), limiar ventilatório (LV), velocidade crítica (VC), capacidade de trabalho anaeróbio (CTAn), desempenho em corrida de 500m e 3km e custo de O2 durante exercício submáximo (C). MÉTODOS: 8 homens fisicamente ativos (20,8±1,6 anos; 74,3±14,9kg) realizaram: 1) Corrida 3km e 500m máximos (Vm3km e Vm500). 2) Teste incremental em esteira para determinação do LL, LV, VO2max e Vmax. 3) Tempo de permanência na Vmax (Tmax), Tempo para atingir o VO2max e Tempo no VO2max. A VC e a CTAn foram obtidas (método linear) a partir dos testes de 3km e 500m. O C foi determinado dividindo-se a velocidade de corrida submáxima pelo respectivo VO2. RESULTADOS: Observou-se alta correlação entre Vm3km e Vmax (r=0,83), Vm3km e VC (r=0,98), Vm500 e VC (r=0,90) e entre Vm500 e Tempo no VO2max (r=0,69). Não foram verificadas diferenças entre LL e LV (178,7±20,0 e 180,7±21,8 m.min-1), sendo o LL altamente correlacionado com Vmax (r=0,91), VC (r=0,96) e Vm3km (r=0,96). Correlação positiva foi observada entre CTAn e C para indivíduos com maior aptidão aeróbia (r=0,79). CONCLUSÕES: As correlações apresentadas entre Vm500 e tempo no VO2max e entre Vm500 e VC indicam que exercícios de curta duração e alta intensidade são positivamente influenciados pela aptidão aeróbia. Devido a correlação significativa com o C, a CTAn se mostra como um possível indicador de ineficiência mecânica no exercício aeróbio
Morphoquantitative study of the aorta’s wall in aerobically trained elderly wistar rats
No full textThe aim of the present study was to evaluate under morphoquantitative aspects possible alterations in the ascending section of the Aorta’s endothelium of elderly Wistar rats (16 months of age) trained at an anaerobic threshold intensity. Ten male animals were divided in two experimental groups (control and exercise, each with 5 animals). The exercise group performed swimming five times per week, 30 minutes per day during eight weeks. Anaerobic threshold was evaluated at the first, fourth and eighth week of training. After the intervention the animals were sacrificed and the heart and Aorta were collected. The Aorta was properly fixed and prepared according to the histology procedures for coloring with Hematoxilin-Eosin, Weigert and Verhoeff. Quantitative and qualitative evaluations were performed using morphometric and stereological methods. There was an increase in the thickness, cross sectional area, elastic fibers and distance between the beams and the nucleus of the smooth muscle without alteration of its diameter (p< .05)
