Evaluation of Health Effects of a First Time Marathon in Young Middle-Aged Men

It is well documented that engaging in regular physical activity is associated
with numerous health benefits, such as a reduced risk of fatal and non-fatal
cardiovascular disease (CVD). However, it is unclear what the upper limits are
regarding the beneficial effects of physical exercise on the CV system and
general health. Marathon running is currently an activity with pronounced
popularity, with predominantly male participants aged 35-50. Correspondingly,
this is the age and gender group where a CVD first becomes clinically evident.
Adverse events such as sudden cardiac arrest (SCA) and sudden cardiac death
(SCD) have been reported among marathon runners, with a 10:1 incidence in men
versus women. Marathon runners may also develop deleterious CV effects, such as
coronary artery calcification, atrial fibrillation and myocardial fibrosis.
Elevations of biomarkers such as myocardial troponins and NT-pro-BNP have also
been demonstrated after acute bouts of endurance running, and changes in
cardiac structures and function have been shown to persist up to 1 week after a
marathon.

No studies have performed a comprehensive longitudinal cardiac evaluation,
including a complete battery of state-of-the-art diagnostic modalities and
continuous monitoring, in first-time marathon runners. Furthermore, running a
marathon after recovery from COVID-19 has never been investigated. Therefore,
we aim to investigate the effects of training for a marathon, performing a
marathon, and recovering from a marathon in first-time male runners, on cardiac
and non-cardiac indices.

Investigate the cardiac and non-cardiac changes of first-time marathon
training, running and recovery in healthy young men, according to COVID-19
status.

A prospective, exploratory cohort study in apparently healthy young middle-aged
first-time male marathon runners. Subjects will be observed for 6 months,
including the different phases of 1) training; 2) the marathon event itself; 3)
recovery. Pre-marathon training will be at the participant's discretion and
unsupervised, but with a standard sports advice (progressive self-training for
4 months). Study evaluations comprise repeated CMR, echocardiography,
cardiopulmonary exercise testing (CPET), ECGs, blood tests and physical
activity reports.

The added risks of participation in this study are negligible. However, the
risks of marathon running carry a certain level of risk,. However, the marathon
running itself is not part of the study protocol, but an individual choice. MRI
has negligible health risks. The cardiac MRI protocol does include the
administration of gadolinium contrast bolus, but gadolinium contrast is well
tolerated with only very rare cases of gadolinium allergy (<0.1%). To exclude
the risk of contrast-induced nephrogenic systemic fibrosis, individuals with a
glomerular filtration rate < 30 ml/min will not be included. The echocardiogram
is a safe, non-invasive procedure using the high-frequency sound waves
(ultrasound). CPET, which involves measuring respiratory gases, is considered a
safe procedure, especially in healthy adults. The 12-lead ECG has no risks, and
subjects may only develop a skin rash from the adhesive ECG pads. The blood
collection has a small risk (<5%), causing a local hemorrhage, which is
unpleasant but harmless. Patients will be offered a guided training by a
licensed coach and a better understanding of the effects of first-time marathon
participation from participation in our study.