With the talk of masks and social distancing in our current climate, which are certainly important ideals, it is a shame that more focus is not put on improving our immune systems. Each of us have a responsibility to keep others healthy by wearing a face covering and keeping our distance, but we have an equal opportunity and responsibility to keep ourselves healthy by incorporating a few key tenets into our routine.
First, it has long been known that regular exercise improves immune function. Campbell and Turner (1) note that regular physical activity or structured exercise reduces the incidence of viral and bacterial diseases as we age, as well as non-communicable diseases such as cancer and chronic inflammatory diseases. They also suggest that exercise creates a 1-2 hour post-workout window where immune cells are redistributed to peripheral tissues, resulting in a transient and time-dependent heightened immune response.
According to da Silveira, et al.(2), this response may be elicited by pro- and anti-inflammatory cytokines that are released after physical activity, as well as a boost in cell recruitment and lymphocyte circulation. All three of these factors combine to create a powerful force in battling viral infections, possibly even SARS-CoV-2, both acutely and chronically although more research is needed in the exact function of exercise and the virus that causes COVID 19.
Often referred to as the "fountain of youth,” regular exercise also acts as a means of slowing the aging process of the immune system. This slowing may occur due to the release of growth hormone post-exercise, an increase in testosterone or other sex-hormones, or an increase in NK cells or NK cell activity (3). This process occurs both during and after a single bout of exercise, as well as repeated bouts leading to an overall improved immune response.
It must be noted that long, strenuous bouts of exercise have been shown in some studies to temporarily increase the susceptibility to upper respiratory infections and therefore are not recommended in order to produce an improved immune system. Instead, moderate exercise for a moderate duration is recommended, both in the form of cardiovascular exercise and strength training.
Armed with this information, how can we best exercise to improve our immune function?
- Exercise regularly - while individual bouts do have some benefit and may create a window of increased immune function, the chronic effects of exercise on the immune system are the most desirable.
- Exercise moderately - this is not the time for workouts that push you to your limits or workouts that last all day.
- A sample week might look like -
a. One day of sprints - 10 short repetitions (10-30 seconds) of running, cycling, swimming, boxing, etc at near max capacity with long recoveries.
b. Two days of lifting heavy - focus on 3-5 sets of 3-12 repetitions with multijoint movements executed with perfect form, depending on age and training experience. The Houstonian’s Personal Trainers are masters at creating these programs for your unique needs.
c. One day of HIIT (High Intensity Interval Training) - this might be a group fitness class or a circuit of exercises that you complete with a high intensity, hence the name, and short rest periods.
d. Three days of easy moving - walking, hiking, swimming gently, cycling easy, tennis, pickleball, golf and gardening might all fit into this category depending on your level of intensity. Just move!
- Incorporate exercise as one part of the five factors in creating a healthy life - movement, nutrition, mindset, recovery (sleep), and connection. Spend a few minutes each day improving each of those five factors and your whole body, including your immune system, will be ready for whatever life throws at you.
By: Personal Trainer Andrew Chaddick, MS, CSCS
References
- Campbell JP, Turner JE. Debunking the Myth of Exercise-Induced Immune Suppression: Redefining the Impact of Exercise on Immunological Health Across the Lifespan. Front Immunol. 2018;9:648. Published 2018 Apr 16. doi:10.3389/fimmu.2018.00648
- da Silveira MP, da Silva Fagundes KK, Bizuti MR, Starck É, Rossi RC, de Resende E Silva DT. Physical exercise as a tool to help the immune system against COVID-19: an integrative review of the current literature [published online ahead of print, 2020 Jul 29]. Clin Exp Med. 2020;1-14. doi:10.1007/s10238-020-00650-3
- Pedersen BK, Hoffman-Goetz L. Exercise and the immune system: regulation, integration, and adaptation. Physiol Rev. 2000;80(3):1055-1081. doi:10.1152/physrev.2000.80.3.1055