CAP. 9 ADAPTAÇÕES CARDIORRESPIRATÓRIAS DO TREINAMENTO. Jack H. Wilmore David L. Constill

Transcrição

1 CAP. 9 ADAPTAÇÕES CARDIORRESPIRATÓRIAS DO TREINAMENTO Jack H. Wilmore David L. Constill

2 Endurance Endurance Resistência Muscular Resistência Cardiorrespiratória Vo2Máx maior taxa de consumo de oxigênio possível de ser atingido o durante um exercício máximo ou exaustivo Exercise in Health and Disease: Evaluation and Prescription for Prevention and Rehabilitation (Pollock,M.L % Wilmore, J.H., 1990)

3 Adaptações cardiovasculares ao treinamento Tamanho do coração Com aumento da demanda do trabalho, o peso e o volume do coração e,consequentemente, a espessura da parede e o tamanho do ventriculo esquerdo aumentam Treinamentos de força x endurance Several methodological considerations and factors confounding the outcome of exercise training in humans have also been omitted when interpreting echocardiographic cross-sectional and longitudinal findings. (Perrault, H., & Turcotte,R.A., 1994)

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5 Volume de Ejeção Por que aumenta com o treinamento? - Frequência Cardíaca - Volume diastólico final - Volume Plasmático - Espessura do ventriculo esquerdo

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8 Frequência cardíaca REPOUSO um batimento por semana com o treinamento Estudo mostra pequenas mudanças em relação a frequência cardiaca de repouso, 65 para 62,4 bpm.

9 SUBMÁXIMA Após 6 meses de treinamento moderado a frequencia cardiaca reduz de 20 a 40 bpm MÁXIMA - Geralmente permanece inalterada

10 Wilmore, J.H. (1996)

11 Débito Cardiaco

12 Fluxo Sanguíneo 4 fatores são responsaveis pelo aumento do suprimento sanguineo: 1 aumento da capilarizaçao 2- Maior abertura dos capilares existentes nos músculos treinados 3 Redistribuiçao sanguínea mais efetiva 4 Aumento do Volume sanguineo *Pesquisa com ratos de Armstrong e Laughlin (1994)

13 Exercise blood flow patterns within and among rat muscles after training. Abstract This study was designed to determine the influence of a long-term, moderate-intensity treadmill training program on the distribution of blood flow within and among muscles of rats during exercise. One group (T) of male Sprague-Dawley rats trained for 1 h/day for wk at 30 m/min on a motor-driven treadmill. A second group (UT) of rats was conditioned for 10 min/day for 4 wk at the same speed. Muscle succinate dehydrogenase activities were higher in T than UT rats indicating a significant training effect. Blood flows (BFs) in 32 hindlimb muscles or muscle parts and other selected organs were measured in the two groups with radiolabeled microspheres during preexercise and while the rats ran for 30 s, 5 min, or 15 min at 30 m/min on the treadmill. The data indicate 1) there were no differences in total hindlimb muscle BF between UT and T rats at any time; however, 2) T rats had higher preexercise heart rates and higher muscle BFs in the deep red extensor muscles, suggesting a greater anticipatory response to the impending exercise; 3) T rats demonstrated more rapid elevations in BF in the red extensor muscles at the commencement of exercise; 4) T rats had higher BFs in red extensor muscles during exercise, whereas UT rats had higher BFs in white muscles; and 5) T rats maintained higher BFs in the visceral organs during exercise. These findings demonstrate that exercise training results in changes in the distribution of BF within and among muscles and among organs during exercise. Specifically, data indicate the highoxidative motor units that are primarily recruited in the muscles during the initial stages of moderate treadmill exercise receive higher blood flows in the trained rats; this presumably contributes to increased resistance to fatigue.

14 Pressão Arterial - Endurance < a pressao arterial em repouso em pessoas hipertensas. - Durante o exercício tem pouco ou nenhum efeito sobre a pressão arterial. - Os mecanismos são desconhecidos

15 Effect of weight training on blood pressure and hemodynamics in hypertensive adolescents (Hagberg, 1984) Six adolescents with persistent essential hypertension were examined to determine the effect of weight training on their blood pressure and hemodynamics. Five had first completed an endurance training program; one subject trained only by weight lifting. All subjects were reevaluated after 5±2 months of weight training, and 12±2 months after cessation of training. Endurance training resulted in an increase in VO 2 and decreases in systolic and diastolic blood pressure. After weight training. VO 2 had decreased to the level found prior to endurance training, and body weight was significantly increased. Systolic blood pressure after weight training was 17±4 mm Hg lower than when measured initially (P<0.01). Weight training maintained the reduction in diastolic pressure elicited by endurance exercise in those who initially had diastolic hypertension. Cessation of all forms of training resulted in no change in body weight, body fat, or VO 2 from the values measured after weight training. Systolic pressure increased significantly with the cessation of training to a value not different from that measured initially. Diastolic pressure also increased after cessation of training. but was still below the initial value. The only significant hemodynamic change found was a reduction in systemic vascular resistance in response to weight training. Weight training in hypertensive adolescents appears to maintain the reductions in blood pressure achieved by endurance training, and may even elicit further reductions in blood pressure.

16 Volume Sanguíneo O treinamento de endurance faz aumentar o volume sanguíneo. Volume plasmático Liberaçao de ADH e Aldosterona Quantidade de proteína plasmática

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18 Adaptações Respiratórias ao treinamento Difusão pulmonar Repouso e durante o exercício submáximo respiratória Frequencia Exercício máximo Difusão pulmonar e a Frequencia respiratória

19 Adaptações Metabólicas ao Treinamento Limiar de lactato

20 Razão de troca respiratoria Relação entre o dioxido de carbono liberado e oxigenio consumido durante o metabolismo de nutrientes. Vo2 Repouso : Não Conclusivo Submáximo : Inalterado ou discreta diminuição

21 The impact of exercise and diet restriction on daily energy expenditure. Poehlman ET 1, Melby CL, Goran MI. Author information 1 College of Medicine, Department of Medicine, University of Vermont, Burlington. Abstract In addition to the direct energy cost of physical activity, exercise may influence resting energy expenditure in 3 ways: (a) a prolonged increase in postexercise metabolic rate from an acute exercise challenge; (b) a chronic increase in resting metabolic rate associated with exercise training; and (c) a possible increase in energy expenditure during nonexercising time. It seems apparent that the greater the exercise perturbation, the greater the magnitude of the increase in postexercise metabolic rate. An exercise prescription for the general population that consists of exercise of low (less than 50% VO2max) or moderate intensity (50 to 75% VO2max) does not appear to produce a prolonged elevation of postexercise metabolic rate that would influence body-weight. Inconsistent results have been found with respect to the effects of exercise training and the trained state on resting metabolic rate. Whereas some investigators have found a higher resting metabolic rate in trained than untrained individuals and in individuals after an exercise training programme, other investigators have found no chronic exercise effect on resting metabolic rate. Differences in experimental design, genetic variation and alterations in energy balance may contribute to the discrepant findings among investigators. A relatively unexplored area concerns the influence of exercise training on energy expenditure during nonexercising time. It is presently unclear whether exercise training increases or decreases the energy expenditure associated with spontaneous or nonpurposeful physical activity which includes fidgeting, muscular activity, etc. The doubly labelled water technique represents a methodological advance in this area and permits the determination of total daily energy expenditure. Concomitant with the determination of the other components of daily energy expenditure (resting metabolic rate and thermic effect of a meal), it will now be possible to examine the adaptive changes in energy expenditure during nonexercising time. A plethora of studies have examined the combined effects of diet and exercise on body composition and resting metabolic rate. The hypothesis is that combining diet and exercise will accelerate fat loss, preserve fat-free weight and prevent or decelerate the decline in resting metabolic rate more effectively than with diet restriction alone. The optimal combination of diet and exercise, however, remains elusive. It appears that the combination of a large quantity of aerobic exercise with a very low calorie diet resulting in substantial loss of bodyweight may actually accelerate the decline in resting metabolic rate. These findings may cause us to re-examine the quantity of exercise and diet needed to achieve optimal fat loss and preservation of resting metabolic rate.

22 Consumo Máximo de oxigênio Aumentos no Vo2 Max e limitações Enzimas Oxidativas (teoria da utilização) Liberação de oxigênio (teoria da apresentação)

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24 Functional adaptations to physical activity and inactivity. Saltin B, Rowell LB.(1980) Abstract Artigo de revisão Rather than focusing on the performance criteria accompanying adaptation to physical activity, this paper emphasizes the magnitudes of alteration in the function of the circulatory, respiratory, and metabolic systems with adaptation. It is our opinion that the limitation of maximal aerobic power resides in the transport of oxygen to working muscle by the circulation. Increases in maximal aerobic power that accompany physical conditioning are attributed primarily to increased maximal muscle blood flow and muscle capillary density. The increase in the oxidative potential of skeletal muscle after training is presented as the mechanism by which capacity for submaximal work is augmented.

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27 Fatores que afetam a Resposta do treinamento aeróbio - Nível de Condicionamento Quanto < o nível de aptidão > a melhora relativa - Hereditariedade Responsável por 25% a 50% dos valores de Vo2máx

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29 I Idade Effect of age and training on aerobic capacity and body composition of master athletes. Pollock ML, Foster C, Knapp D, Rod JL, Schmidt DH. (1987) Abstract Maximum oxygen uptake (VO2max) and body composition have been shown to deteriorate with age. How much of the decline is attributable to aging and how much is affected by reduced physical activity is not known. The purpose of this investigation was to determine the aerobic capacity and body composition of 24 master track athletes and to evaluate the relationship to age and maintenance of training over a 10-yr period. The subjects (50-82 yr of age) were retested after a 10.1-yr follow-up (T2). All continued their aerobic training, but only 11 were still highly competitive (COMP) and continued to train at the same intensity. The other 13 athletes studied became noncompetitive (post-comp) and reduced their training intensity. The results showed the COMP group to maintain its VO2max and maximum O2 pulse while the post-comp group showed a significant decline ( vs ml X kg-1 X min-1; vs ml/beat from test one (T1) to T2 for the COMP vs. post-comp groups, respectively). Maximum heart rate declined 7 beats/min for both groups. Body composition showed no difference between groups from T1 to T2. For both groups body weight declined slightly ( kg), percent fat increased significantly ( %), and fat-free weight decreased significantly ( kg). Thus, when training was maintained, aerobic capacity remained unchanged over the follow-up period. Body composition changed for both groups and may have been related to aging and/or the type of training performed.

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