Nutrition Guidelines

Fitness

Exercise and Upper Respiratory Tract Infections

People who were
physically active had
20-30% fewer colds
than inactive people.

Download PP Slide
for this study

Upper respiratory tract infections (URTIs) are primarily caused by viruses and are the most common infections experienced. While they are usually moderate in symptoms, they do cause high levels of work loss days (see first article) and added expense for productivity losses.

The Massachusetts Medical School recently did a study comparing URTI (colds and flu) and physical activity in a group of 547 healthy adults. They tracked physical activity levels and the number of URTIs each person experienced over a period of a year. At the end of the year, they divided people into quartiles based on how much exercise they got.

People who were most active (the top 25%) had from 20-30% fewer colds per year compared to those most inactive (bottom 25%). Men seemed to benefit the most with 34% fewer colds in the active group and women 20% fewer colds.

Results were adjusted for age, smoking, dietary factors, vitamin supplements, presence of children in the home and other possible confounders, but the relationship held true. Regular moderate physical activity protects against common URTIs.

Other research shows that in competing athletes, at very high intensity exercise and long duration, their is actually an increase in the number of URTIs. Getting adequate exercise but not over doing it is most beneficial. Ways that exercise may protect against infections include the following observed changes following regular exercise:

Exercise increases the number of circulating neutrophils and lymphocytes, white blood cells that fight infection
Exercise increases the number of circulating natural killer cells and cytokines, key immune function factors
These effects may last for several hours following each exercise bout
Regular exercise improves natural killer cell activity

One good way to prevent illness and reduce expense from work loss days is to encourage regular, moderate exercise. Last year 100 million colds were responsible for 250 million days of restricted activity and 30 million lost days of work!

Fitness

Reference

References

Top

Matthews CE, et al. Moderate to vigorous physical activity and risk of URTI, Medicine and Science in Sports and Exercise, 2002; 34:1242-1248

Making Healthy Choices articles are written by Don Hall, DrPH, CHES president of LifeLong Health with contributions from associated health professionals. Content is general health information from evidence based research. It's purpose is not to treat disease or take the place of advice by your doctor but to promote healthy lifestyles. Persons with health problems should contact their physician for specific guidance.

Updated: 2-27-03 DRH