PEDS200 Lecture : Cardio-Respiratory Exercise Physiology-2
Document Summary
Vo2 max: max rate o2 can be taken into body, transported, utilized to perform work. 1. central: o2 transport: dependent on hr, sv, q, blood volume, oxygenation, blood flow. 2. peripheral: o2 utilization: dependent on capillarization of muscle fibers, oxidative capacity, fiber type. Exercise-induced hypoxaemia: not enough o2 getting into blood. Cardiac hypertrophy: incr. cavity size of ventricle, wall thickness. Decr. resting hr (decr. sympathetic drive, incr. parasympathetic drive) Qmax, svmax, max muscle blood flow, a-vo2 diff(o2 extraction) Pressure overload: pressure from high afterload, forces heart to contract harder against resistance, increase wall thickness (concentric hypertrophy) Volume overload: volume due to high preload, incr. stretch on cavity ->incr. size (eccentric hypertrophy) Blood doping: incr. hematocrit, hemoglobin, blood volume, vo2 max: early: remove, wait, re-infuse. (incr. heart stress due to hemoconcentration, modern: erythropoietin (epo): incr. Rbc prod. , higher [hb] (result in stroke, heart attack, pulmonary edema, death)