AUTHOR=D’Silva Andrew , Bhuva Anish N. , van Zalen Jet , Bastiaenen Rachel , Abdel-Gadir Amna , Jones Siana , Nadarajan Niromila , Menacho Medina Katia D. , Ye Yang , Augusto Joao , Treibel Thomas A. , Rosmini Stefania , Ramlall Manish , Scully Paul R. , Torlasco Camilla , Willis James , Finocchiaro Gherardo , Papatheodorou Efstathios , Dhutia Harshil , Cole Della , Chis Ster Irina , Hughes Alun D. , Sharma Rajan , Manisty Charlotte , Lloyd Guy , Moon James C. , Sharma Sanjay TITLE=Cardiovascular Remodeling Experienced by Real-World, Unsupervised, Young Novice Marathon Runners JOURNAL=Frontiers in Physiology VOLUME=11 YEAR=2020 URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2020.00232 DOI=10.3389/fphys.2020.00232 ISSN=1664-042X ABSTRACT=Aims

Marathon running is a popular ambition in modern societies inclusive of non-athletes. Previous studies have highlighted concerning transient myocardial dysfunction and biomarker release immediately after the race. Whether this method of increasing physical activity is beneficial or harmful remains a matter of debate. We examine in detail the real-world cardiovascular remodeling response following competition in a first marathon.

Methods

Sixty-eight novice marathon runners (36 men and 32 women) aged 30 ± 3 years were investigated 6 months before and 2 weeks after the 2016 London Marathon race in a prospective observational study. Evaluation included electrocardiography, cardiopulmonary exercise testing, echocardiography, and cardiovascular magnetic resonance imaging.

Results

After 17 weeks unsupervised marathon training, runners revealed a symmetrical, eccentric remodeling response with 3–5% increases in left and right ventricular cavity sizes, respectively. Blood pressure (BP) fell by 4/2 mmHg (P < 0.01) with reduction in arterial stiffness, despite only 11% demonstrating a clinically meaningful improvement in peak oxygen consumption with an overall non-significant 0.4 ml/min/kg increase in peak oxygen consumption (P = 0.14).

Conclusion

In the absence of supervised training, exercise-induced cardiovascular remodeling in real-world novice marathon runners is more modest than previously described and occurs even without improvement in cardiorespiratory fitness. The responses are similar in men and women, who experience a beneficial BP reduction and no evidence of myocardial fibrosis or persistent edema, when achieving average finishing times.