Exercise and Atrial Fibrillation: The Dose Makes the Poison? A Narrative Review.

"All things are poison, and nothing is without poison; the dosage alone makes it so a thing is not a poison" (Paracelsus, ~ 1538 AD). This well-known quote seems to aptly summarize the current understanding of the interaction between exercise and atrial fibrillation (AF). A host of data strongly suggests that regular exercise has a protective effect against developing AF. A small but well-conducted group of trials also demonstrates beneficial effects of exercise in the treatment of AF. Recently, however, potentially detrimental effects of large volumes of high-intensity exercise on the probability of developing AF have moved into the sports-cardiological focus. This effect is well documented for elite athletes; data regarding the general population is less clear. This review presents the current data regarding the protective, therapeutic and potentially risk-enhancing effects of exercise regarding AF. The authors demonstrate that the benefits are clear and strongly outweigh the potential disadvantages.

Cellular Integrative Immune Markers in Elite Athletes.

The integrative immune markers neutrophil-lymphocyte-ratio (NLR), platelet-lymphocyte-ratio (PLR) and systemic immune inflammation index (SII) are established markers in clinical patient care. Adoption of these markers in elite athletics might prove beneficial for monitoring training and health. Blood samples of 195 healthy national Olympic squad athletes were collected before a graded bicycle-ergometric exercise test until complete exhaustion. Measurements included white blood cells, lymphocytes and platelets, allowing for the calculation of the integrative immune markers. Correlations between athlete characteristics (sex, age, sporting discipline, training experience, training volume) and integrative immune marker-values were assessed. In a subgroup analysis a second blood sample was collected from 25 athletes at 1 minute after exercise test to assess its effect on the immune marker levels.An inverse correlation between peak power output and SII-level (Pearson correlation coefficient=-.270, p<.001) and NLR-level (Pearson correlation coefficient=-.249, p<.001) was found. Athletes with higher aerobic fitness had significantly lower values of SII and PLR compared to athletes with lower aerobic fitness. An elevated SII (p=.003) and a reduced PLR (p=.001) was documented as acute response to the exercise test. The integrative immune markers might be a promising tool for monitoring training and health in elite athletes.