The Effect of Intermittent Fasting on Acute Subconcussive Head Impacts

The purpose of this study is to examine the effect of intermittent fasting on the acute neural responses to subconcussive head impacts. The study is designed to identify the effects of 20 controlled soccer headings in college-aged soccer players in one of four groups (fasted, pre-fasted, post-fasted, or control) through the use of neural-injury blood biomarkers, magnetic resonance spectroscopy, functional, and diffusion MRI, and ocular-motor function across 4 acute time points. The central hypothesis is that the neuronal structural, physiological, and functional impairments from the subconussive head impacts will be lessened by intermittent fasting either before or after the soccer headings. The neural-injury blood biomarkers neurofilament light (NfL), glial fibrillary acidic protein (GFAP), Ubiquitin C-Terminal Hydrolase L1 (UCH-L1), and Tau will be measured in serum, with the hypothesis that fasting prior to the 20 soccer headings will result in a decreased heightened response compared to the post-heading fasted group and the controls. It is also hypothesized that repetitive subconcussive head impacts will impair neurocognitive function, as measured by regional changes in fMRI activation during a working memory task in the fasted groups. Twenty headings will significantly alter fMRI activation in the fasted groups from baseline. This impairment will not be observed in the control group. White matter microstructure will be measured by diffusion imaging metrics, with the hypothesis that 20 soccer headings will significantly disrupt microstructure in the fasted groups compared to baseline, but not in the control group. The study will also assess neuro-opthalmologic function as measured by the King-Devick test (KDT) and oculomotor function as measured by near-point-of-convergence (NPC) in response to subconcussive head impacts. The hypothesis is that NPC performance will be significantly impaired for longer than 24 hours in all the groups, but this impairment will be greater in the control group, and that the learning curve and expected improvement of KDT will be significantly blunted in both groups, with a display worsening in the control group.