{"id":151762,"date":"2025-11-30T12:18:06","date_gmt":"2025-11-30T17:18:06","guid":{"rendered":"https:\/\/runningmagazine.ca\/?p=151762"},"modified":"2025-12-01T14:18:32","modified_gmt":"2025-12-01T19:18:32","slug":"your-marathon-brain-could-be-making-you-sick","status":"publish","type":"post","link":"https:\/\/runningmagazine.ca\/health-nutrition\/your-marathon-brain-could-be-making-you-sick\/","title":{"rendered":"Your marathon brain could be making you sick"},"content":{"rendered":"

Maybe you’ve experienced it: you cross the finish line of your marathon feeling strong, only to wake up a day later with a sore throat and a headache. It turns out the problem might not be the race itself, but everything swirling in your head beforehand. In a study<\/a> published in the European Journal of Sport Science, <\/em>a group of researchers from Liverpool John Moores University and Bangor University set out to understand why so many runners catch a cold after a marathon, and the answer wasn’t just about hard training days and logging big mileage.<\/p>\n

\"tired<\/p>\n

Inside the pre-run mood check<\/h2>\n

The group followed more than 400 marathoners in the weeks before a race. Along with the usual performance and training questions, the runners reported how they were feeling emotionally\u2014anxious, calm, irritable, keyed up<\/a>. They also gave saliva samples both before and after the race. Then the runners logged how they felt over the next two weeks, including any cold-like symptoms. The researchers were looking at markers tied to what\u2019s called mucosal immunity, basically the first-line defence in your mouth and throat against the viruses that cause common colds.<\/p>\n

\"runner<\/p>\n

 <\/p>\n

The link between nerves and getting sick<\/h2>\n

The researchers observed a clear pattern. Runners who reported higher stress, anxious thoughts or unsettled moods before the race were more likely to experience a dip in mucosal immunity, and they were also the ones who tended to contract a cold after the marathon. The researchers conducted a second, smaller study in the lab, this time using an hour-long treadmill run, and observed a similar effect, particularly in men. If your stress levels were already running high, the body\u2019s first line of defence didn\u2019t bounce back as smoothly.<\/p>\n

The story was less straightforward in women, likely because hormones, cycle phase and contraceptive use<\/a> can all influence immune markers. The researchers were clear that more work needs to be done there.<\/p>\n

\"\"<\/p>\n

How stress and long runs team up<\/h2>\n

The takeaway isn\u2019t that running makes you sick. It\u2019s that psychological stress and physical stress can pile on top of each other, and when they do, your immune system<\/a> sometimes pays the price. Long runs and the race build-up already nudge your system, and if you\u2019re also juggling nerves, poor sleep, hectic travel or life stress, that nudge gets a little stronger.<\/p>\n

Faith Kipyegon’s secret for calming race-day nerves<\/a><\/p><\/blockquote>\n