Comparative electroencephalography analysis: Marathon runners during tapering versus sedentary controls reveals no significant differences.

INTRODUCTION: Previous studies described various adaptive neuroplastic brain changes associated with physical activity (PA). EEG studies focused mostly on effects during or shortly after short bouts of exercise. This is the first study to investigate the capability of EEG to display PA-induced long-lasting plasticity in runners compared to a sedentary control group. METHODS: Thirty trained runners and 30 age- and sex-matched sedentary controls (SC) were included as a subpopulation of the ReCaP (Running effects on Cognition and Plasticity) study. PA was measured with the International Physical Activity Questionnaire (IPAQ). Resting-state EEG of the runners was recorded in the tapering phase of the training for the Munich marathon 2017. Power spectrum analyses were conducted using standardized low-resolution electromagnetic tomography (sLORETA) and included the following frequency bands: delta: 1.5-6 Hz, theta: 6.5-8.0 Hz, alpha1: 8.5-10 Hz, alpha2: 10.5-12.0 Hz, beta1: 12.5-18.0 Hz, beta2: 18.5-21.0 Hz, beta3: 21.5-30.0 Hz, and total power (1.5-30 Hz). RESULTS: PA (IPAQ) and BMI differed significantly between the groups. The other included demographic parameters were comparable. Statistical nonparametric mapping showed no significant power differences in EEG between the groups. DISCUSSION: Heterogeneity in study protocols, especially in time intervals between exercise cessation and EEG recordings and juxtaposition of acute exercise-induced effects on EEG in previous studies, could be possible reasons for the differences in results. Future studies should record EEG at different time points after exercise cessation and in a broader spectrum of exercise intensities and forms to further explore the capability of EEG in displaying long-term exercise-induced plasticity.

Marathon running improves mood and negative affect.

BACKGROUND: Physical activity has beneficial effects on depression, as well as on other mental and somatic diseases. The amount of recommended exercise is still under discussion. We investigated whether marathon runners (MA) exhibit less or more depressive symptoms and negative affects compared to sedentary controls (SC) and how their mood changes in the context of marathon training and marathon running. METHODS: We included 100 amateur marathon runners and 46 age- and gender matched sedentary controls in the ReCaP (Running effects on Cognition and Plasticity) study. Questionnaires contained Beck Depression Inventory (BDI), Hamilton Depression Scale (HAMD), Oxford Happiness Questionnaire (OHQ), Visual Analogue Scale (VAS), Positive And Negative Affect Schedule (PANAS), Global Assessment of Functioning (GAF). SC were evaluated one time at baseline, MA six times during the six months study period. RESULTS: Compared to SC, marathon runners (281.80 ± 131.44 running min/week) exhibited less depressive symptoms, more positive affects (PANAS-PA) and a higher level of functioning (GAF). Within the marathon group, negative affect (PANAS-NA) decreased and general mood states (VAS) further improved throughout the study period with a maximum 24 h after the marathon. DISCUSSION: MA had less depressive symptoms and a higher level of functioning compared to SC. Higher amounts than the recommended duration of 150 min/week aerobic training (WHO/ACSM) and the participation in a marathon seem to even further improve negative affect. These findings give new insight into the relationship between exercise and mood parameters. They can be implemented in future preventive strategies for depressive symptoms.

Running effects on cognition and plasticity (ReCaP): study protocol of a longitudinal examination of multimodal adaptations of marathon running.

Regular moderate physical activity (PA) has been linked to beneficial adaptations in various somatic diseases (e.g. cancer, endocrinological disorders) and a reduction in all-cause mortality from several cardiovascular and neuropsychiatric diseases. This study was designed to investigate acute and prolonged exercise-induced cardio- and neurophysiological responses in endurance runners competing in the Munich Marathon. ReCaP (Running effects on Cognition and Plasticity) is a multimodal and longitudinal experimental study. This study included 100 participants (20-60 years). Six laboratory visits were included during the 3-month period before and the 3-month period after the Munich marathon. The multimodal assessment included laboratory measurements, cardiac and cranial imaging (MRI scans, ultrasound/echocardiography) and neurophysiological methods (EEG and TMS/tDCS), and vessel-analysis (e.g. retinal vessels and wave-reflection analyses) and neurocognitive measurements. The ReCaP study was designed to examine novel exercise-induced cardio- and neurophysiological responses to marathon running at the behavioral, functional and morphological levels. This study will expand our understanding of exercise-induced adaptations and will lead to more individually tailored therapeutic options.

Motor-cortex excitability and response variability following paired-associative stimulation: a proof-of-concept study comparing individualized and fixed inter-stimulus intervals.

While diverging efficacy and inter-individual response variability have repeatedly been reported for paired-associative stimulation (PAS), approaches to overcome these issues are yet lacking. Hence, the aim of the present study was to determine whether response variability could be reduced through the application of an individualized PAS paradigm. Changes of transcranial magnetic stimulation (TMS) elicited motor-evoked potentials (MEP) following different PAS paradigms were assessed in three experimental conditions. According to a within-subjects design, 21 participants received three consecutive PAS paradigms differing with respect to the applied inter-stimulus intervals (ISI) between peripheral nerve stimulation (PNS) and TMS. Based on foregoing considerations, we compared fixed ISI of 25 ms (PAS 25) and 22 ms (PAS 22) to an individualized PAS paradigm accounting for conduction time differences on the single subject level (iPAS). Overall, we did not observe significantly increased post-stimulation MEP magnitudes in any of the three experimental paradigms. Explorative analyses revealed increased inter-individual response variability in case of PAS 25 and PAS 22 compared to higher rates of expected MEP magnitude increases in case of our iPAS paradigm. The findings of our proof-of-concept study points towards a potential association of decreased inter-individual variability with individually selected ISI that account for differences in conduction time. However, as our findings did not reach the significance threshold, our study highlights the issue of intra-individual variability in PAS paradigms. Further replication studies with larger sample sizes and repetitive designs are needed to confirm our findings.