MRI of the brain. Male, 52-years-old. A1: stage 57, 3,971 km (T1w turbo FLASH 3D sagittal): High resolution isometric three-dimensional sequence (1 mm) allows isovoxel based volumetry (VBM) of the whole brain. A2: Three-dimensional view shows dominant areas of volume loss (colored) of grey brain matter occurring during the TEFR09. B: stage 36, 2,448 km (T2w FLAIR): Sensitive sequence for detection of brain lesions. In this case, no lesions visible. C: 20 days before the start. Functional MRI (fMRI) using blood oxygenation level dependent (BOLD) contrast for evaluation of pain perception in ultra runners (C1: without pain stimulus, C2: with pain stimulus). C3: Post-processing analysis using statistical parametric mapping (SPM) shows areas of activation.