ECSS Paris 2023: CP-MH03
INTRODUCTION: It is well known that ultra-endurance races such as a full distance ironman triathlon causes damage to skeletal and cardiac muscles. However, the underlying factors causing these disturbances are less investigated. In this study we investigated if there is an association between ground reaction forces, measured with accelerometry, during the marathon part of an Ironman triathlon and markers of skeletal and cardiac muscle damage. Our hypothesis was that higher ground reaction forces are positively associated with skeletal and heart muscle damage with no gender differences.The overall results of the race have been reported previously [1, 2]. 1. Danielsson T, Schreyer H, Woksepp H, et al. BMJ Open Sport Exercc Med 2019;5:e000486 2. Danielsson T, Carlsson J, Bergman P, et al. Scientiffic Reports 2020;10:901 METHODS: Twenty (8 women) participants completed a full distance ironman triathlon (3.8 km swimming, 180 km cycling and 42 km running) and provided a full set of data and were included in the analysis. As markers for skeletal muscle damage, creatine kinase (CK) and myoglobin was analysed. As markers for cardiac muscle damage cardiac troponin t (cTnT), the N-terminal of the prohormone brain natriuretic peptide (NT-proBNP) was analysed. Ground reaction forces were estimated using an accelerometer (ActiGraph GT3x). Based on the official transition times we sliced out the raw accelerations for the marathon part of the race and calculated the mean vector magnitude (VM) expressed in milliG per second (mG/s). Due to outliers among the dependent variables, Spearman rank correlations (rho) stratified by sex was calculated. RESULTS: No significant association between the biomarkers and mechanical stress was observed (all p>0.05). CONCLUSION: We did not find any support for our hypothesis of a positive association between ground reaction forces and markers of skeletal and heart muscle damage. The small sample size in the groups and the fact that we did not adjust for any potential confounder in this study warrants caution in the interpretation of the results.
Read CV Tom DanielssonECSS Paris 2023: CP-MH03
INTRODUCTION: In incremental exercise tests, a significant decrease in vagal activity occurs as exercise intensity rises. This reduction in vagal tone results from the autonomic nervous systems (ANS) response to increased physical demands. As individuals move from rest to higher exertion levels, the sympathetic nervous system becomes more dominant, leading to an elevated heart rate (HR) and reduced heart rate variability (HRV). This shift in autonomic balance highlights the bodys need to deliver more oxygen and nutrients to active muscles, showcasing the complex interaction between the cardiovascular and nervous systems during exercise. Despite this understanding, insights into HRV behavior during sports medical tests for issuing exercise certificates are limited. Thus, we aimed to assess the timing of vagal suppression and its recovery during maximal tests in the Italian clinical context. METHODS: Following the Italian Ministry of Healths suggestion, the ECGs of twenty-three healthy men who underwent an incremental test on the cycle ergometer were recorded. The protocol involves a consistent load increase of 25 W every 30 seconds until reaching 85% of the theoretical maximum heart rate (HR85%theory). Tests were preceded by a 1-minute resting period and a 30-second warm-up at a fixed intensity of 50 W. The following recovery phase was divided into 30 seconds of pedaling without load and 2 minutes of rest. At each phase of the protocol, the root mean square of successive beats (RMSSD) and the HR were calculated. RESULTS: A repeated measures Friedman test confirmed that RMSSD decreased along with the increased workload required (-42% from the rest phase to the end of the test, p < 0.001). However, the RMSSD at the final stage of recovery did not differ from the rest phase (p = 0.85), nor did the RMSSD observed during the first step of the test vary from that recorded at the beginning of recovery (p = 0.08). Moreover, the RMSSD during the resting phase also showed a significant correlation with its counterpart at the end of the test (rho = 0.47; p = 0.025). In parallel, a paired t-test demonstrated that the maximal HR achieved at the end of the test presented values similar to those of the HR85%theory (p > 0.05). CONCLUSION: The lower RMSSD value observed during the incremental step test confirms that this protocol is sufficiently stressful for the ANS without compromising the cardiovascular system. As mandated by Italian authorities, this protocol aims to determine whether the participant is suitable for competitive sports, considering the underestimation of the actual maximal HR. From the ANS perspective, it was confirmed that there was greater reactivity at the end of the recovery, demonstrating a similar autonomic balance to the results in the resting phase. Furthermore, participants with higher RMSSD values at rest maintained elevated RMSSD levels at the end of the test, reaffirming previous findings regarding the extent of vagal suppression in maximal tests based on resting values.
Read CV Jorge Lopes StornioloECSS Paris 2023: CP-MH03
INTRODUCTION: The atria make a significant contribution to ventricular filling and thus to cardiac output. Due to regular exercise-induced volume and pressure overload endurance athletes may develop atrial dilation, leading to a reduction in atrial reservoir and booster function. This reduction of atrial function can already be observed after 16 weeks of endurance training.1 To investigate whether changes in atrial function may also occur during a single ultra-endurance event we analysed the atrial adaptions during the 64-day TransEuropeFootRace. METHODS: 20 athletes (18 men, 2 women, age 26-65 (50.3 ± 10.0) years) ran 4,487 km at an average of 70.1 km/day. Cardiac magnetic resonance imaging (cMRI) was obtained at three time points: T1 after 294.3 ± 134.7 km, T2 after 1735.3 ± 85.7 km and T3 after 3369.8 ± 89.7 km. 8 months after the race (Tpost) 10 athletes returned for a follow-up scan. Atrial function was analysed by longitudinal strain analysis. Since atrial function is substantially influenced by ventricular filling pressures, we also analysed left ventricular diastolic function using the ratio of mitral peak early to late diastolic filling velocity (MV E/A). We fitted linear mixed models for all strain parameters. Means of the parameters were compared pairwise by Tukey test at all time points. Multiple imputation was used to account for uncertainty due to missing data. RESULTS: Left and right atrial reservoir strain and right atrial booster strain remained unchanged over the course of the race. MV E/A also remained unchanged. However, we found evidence for a significant change in left atrial booster strain in both 4- (F(3; 45.83) = 3.99, p = 0.013) and 2-chamber views (F(3; 45.74) = 3.77, p = 0.017). In the 2-chamber view, left atrial booster strain decreased significantly between T2 and T3 (20.15 ± 4.41%, 15.55 ± 6.63%, p = 0.045). In the 4-chamber view, there was a significant increase in left atrial booster strain between time points T2 and Tpost (10.19 ± 4.76%, 17.07 ± 11.03%, p = 0.039). CONCLUSION: Cardiac imaging provides evidence of partial decline in left atria booster strain after approximately 45 days of the TransEuropeFootRace. As the left ventricular diastolic function remained stable this decline might be intrinsic to the left atrium. A possible regeneration of left atrial booster strain is suggested by the follow-up cMRI (Tpost) of a sub-sample. 1 DAscenzi, F., et al. (2014). Morphological and functional adaptation of left and right atria induced by training in highly trained female athletes. Circulation. Cardiovascular imaging, 7(2), 222–229. https://doi.org/10.1161/CIRCIMAGING.113.001345
Read CV Luisa PrechtlECSS Paris 2023: CP-MH03