Network Physiology of Exercise: Beyond Molecular and Omics Perspectives

Abstract

Molecular Exercise Physiology and Omics approaches represent an important step toward synthesis and integration, the original essence of Physiology. Despite the significant progress they have introduced in Exercise Physiology (EP), some of their theoretical and methodological assumptions are still limiting the understanding of the complexity of sport-related phenomena. Based on general principles of biological evolution and supported by complex network science, this paper aims to contrast theoretical and methodological aspects of molecular and network-based approaches to EP. After explaining the main EP challenges and why sport-related phenomena cannot be understood if reduced to the molecular level, the paper proposes some methodological research advances related to the type of studied variables and measures, the data acquisition techniques, the type of data analysis and the assumed relations among physiological levels. Inspired by Network Physiology, Network Physiology of Exercise provides a new paradigm and formalism to quantify cross-communication among diverse systems across levels and time scales to improve our understanding of exercise-related phenomena and opens new horizons for exercise testing in health and disease.

Inter-muscular networks of synchronous muscle fiber activation

“…), and 3) investigate synchronized cross-frequency communication among different muscles and key organ systems, such as the brain and related cortical rhythms (Ciria et al, 2019;Rizzo et al, 2020Rizzo et al, , 2022. Extending investigations in these directions would lay down the first building blocks of a new interdisciplinary area of research, Network Physiology of Exercise (Balagué et al, 2020, Balagué et al, 2022a.…”

Functional networks of muscle fibers facilitate inter-muscular coordination

“…), and (iii) investigate synchronized cross-frequency communication among different muscles and key organ systems, such as the heart or the brain and related cortical rhythms 29,63,64 . Extending investigations in these directions would lay down the first building blocks of a new interdisciplinary area of research, Network Physiology of Exercise [65][66][67] .…”

Cardiorespiratory Coordination in Collegiate Rowing: A Network Approach to Cardiorespiratory Exercise Testing

“…Another limitation of this study may be due to the applied discontinuous incremental rowing protocol to exhaustion, as continuous time series of the involved physiological variables were recorded and analyzed, but in a discontinued way. In order to capture interactions among physiological systems with PCA, a continuous time series analysis using a continuous CPET has been proposed [ 57 ]. This study examined the NPE framework in rowing using the PCA method, and for field applicability was decided to use a discontinuous incremental protocol instead of a continuous one.…”

“…It has been proposed that the synergism of the cardiovascular and respiratory systems during a sub maximum or maximum exercise stimulus cannot be captured by the traditional VO 2max tests [ 52 ]. The framework of Network Physiology and, more specifically, Network Physiology of Exercise (NPE) [ 51 , 53 , 54 , 55 , 56 , 57 , 58 ] utilizes non-linear modeling and time series analysis of coordinative variables to investigate how different physiological systems coordinate and synchronize as a network [ 59 , 60 , 61 , 62 ]. For example, cardiorespiratory coordination (CRC) has been recently proposed as an alternative method to assess the synergism between the cardiorespiratory variables during an exercise stimulus [ 52 , 63 , 64 , 65 , 66 , 67 ].…”