Our immune system is one of the amazing cellular networks in our body. This system has come into direct focus as we face the COVID pandemic and try to improve our immunity to this virus through vaccinations. In addition to avoiding exposure through social distancing individuals often search for ways to boost their immune response. Despite claims and marketing efforts the basics of sleep, nutrition, and exercise may be our best options to improve our immunity.
Researchers have previously established fit individuals report fewer infections and illnesses, as well as, have higher resting levels of immune cells and stronger responses to bacteria and viruses. More recently we have seen the health benefits of an exercise session on immunity. Although authors have found a temporary reduction in immunity following intense exercise sessions, these individuals become protected as they become more trained over time. Conversely, moderate exercise has been associated with an improved immune response. A prior study demonstrates the impact of low to moderate exercise on infection incidence.
Chubak and colleagues published their results of their randomized controlled trial on walking and future incidence of infections (Am J Med. 2006). Authors recruited over 100 overweight and obese females and randomized them to one of two groups. The first group attended a 45 minute stretching session once a week while the 2nd group received 45 minutes of moderate exercise 5 days a week. These group allocations were maintained over 12 months as the researchers monitored the incidence of colds among these women. Authors reported a decreased risk of colds among the exercisers with a three times higher risk of illness among the stretching group.