Strenuous exercise, such as running a half marathon, can lead to a temporary increase in markers of acute inflammation, such as white blood cells, cytokines and creatine kinase, compromised immunity, and skeletal muscle damage [
2,
3]. Running a half marathon may also result in blisters, loss of toenails, temporary loss of muscle force generating capacity, and feelings of muscle pain and tenderness following the event [
3]. These symptoms may last hours or days, depending on fitness level, recovery, age and genetics.
Running a half marathon may also lead to dehydration, depleted muscle glycogen stores and fatigue. Some people experience digestive changes and loss of appetite immediately after a half marathon, followed by a stronger appetite in the days following. Incorporating proper recovery after a half marathon is important to counteract muscle breakdown, decrease inflammation and speed up recovery [
4].