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Correlation Differences in Heartbeat Fluctuations During Rest and Exercise

Roman Karasik·Nir Sapir·Yosef Ashkenazy·Plamen Ch. Ivanov·Itzhak Dvir·Peretz Lavie·Shlomo Havlin
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Abstract

We study the heartbeat activity of healthy individuals at rest and during exercise. We focus on correlation properties of the intervals formed by successive peaks in the pulse wave and find significant scaling differences between rest and exercise. For exercise the interval series is anticorrelated at short time scales and correlated at intermediate time scales, while for rest we observe the opposite crossover pattern -- from strong correlations in the short-time regime to weaker correlations at larger scales. We suggest a physiologically motivated stochastic scenario to explain the scaling differences between rest and exercise and the observed crossover patterns.

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Roman Karasik, Nir Sapir, Yosef Ashkenazy, Plamen Ch. Ivanov, Itzhak Dvir, Peretz Lavie, Shlomo Havlin. 2001-10-26. Correlation Differences in Heartbeat Fluctuations During Rest and Exercise. https://doi.org/10.1103/physreve.66.062902

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