With the dreaded flu season on the horizon, we know you’re looking for ways to boost your immune system and protect yourself. After all, not only does it leave you feeling lousy, the flu can sideline you for a week or longer, seriously impacting your life and productivity.

We recently shared a list of immune-boosting foods, and we received an influx of great feedback, and we wanted to complement that with 3 more key strategies to help support a properly-functioning immune system and help keep you healthy this flu season.

Exercise…But Not Too Much. It’s no surprise that being sedentary makes you more susceptible to getting upper respiratory tract infections (URTI) like the flu, but did you know that too much exercise can impair the body’s defense system, making avid exercisers and hard-training athletes more susceptible to getting sick? On the other hand, moderate exercise can decrease one’s risk of getting URTI by enhancing immune function.

Take a Chill Pill. Too much stress — whether real or perceived — can also increase your susceptibility to contracting the cold and flu. In one study published in the prestigious New England Journal of Medicine, which examined the relationship between psychological stress and the frequency of the common cold among 394 healthy participants intentionally exposed to respiratory viruses, found that the more stressed the participants felt, the more likely they were to get sick. Studies have also shown that stressful life events, daily hassles, and negative mood states are predictive of experiencing more flu-like symptoms. What’s more, it appears that the longer that stress persists, the greater the risk of infection.

All that is to say that regularly practicing stress management is a linchpin in keeping you healthy. Set boundaries, practice yoga, meditate, take walks, breathe deeply and slowly, exercise, and practice reframing to help boost your immune system and keep your stress levels in a healthy range.

Get Your Beauty Rest. Looking for a surefire way to get sick this cold and flu season? Don’t get enough sleep, which is an important predictor of immunity. A study published in JAMA Internal Medicine, which examined the relationship between sleep duration and the incidence of contracting the cold virus among 153 healthy men and women, found that participants who slept 7 hours or less were nearly 3 TIMES more likely to develop a cold than those who slept 8 hours or more. The researchers also found that sleep efficiency (which is the percentage of time a person actually sleeps between lying down to sleep and waking up the next morning) played a tremendous role. Specifically, they found that participants with poorer quality of sleep (> 92% efficiency) were 5 ½ TIMES more likely to develop a cold than those with 98% or better efficiency.

So, if you want to boost your immune system and stay healthy, practice healthy sleep hygiene habits and aim for about 8 hours of sleep each night.