Variabilidade da frequência cardíaca: método não-invasivo de avaliação do limiar ventilatório

Exercise intensity is one of the main variables in planning and implementing physical training. Many methods are used to quantify this exercise intensity. Heart rate is a commonly used method to determine it, which is generally done by estimating maximum heart rate from the equation 220 - age. Maximal oxygen consumption and lactate threshold are widely used in order to measure exercise intensity. However, these techniques present limitations as they are exclusive to laboratory and demand expensive equipments. Using heart rate for determining precisely exercise intensity would be easier and less expensive than the above techniques. Variations that occur between RR intervals or between two consecutive heart beats are called heart rate variability (HRV) and have been used in the clinical set for detection of cardiac disorders. Recent investigations