Fueling a Strong Immune System


By Dave Ellis, RD


In season, it’s all about performing on a consistent basis over the course of the entire season. As a team, hanging onto hard-fought offseason gains during the long grind of the in-season schedule sets the stage for a productive roster in the second half of the season. It doesn’t matter how talented a roster you have; if the team is run down from illness and weak from lack of in-season maintenance training, a successful run at postseason play may not be in the cards. The underpinnings of a strong immune system to avoid illness in-season are…

1) The quality and quantity of your rest, and

2) The quality of your diet, especially from foods like fresh fruits, vegetables, nuts, and seeds. These immune-enhancing foods improve your body’s resilience to stress that comes from playing those long double headers and not-so-great night’s sleep that comes when traveling in vans or buses. If you are not eating a salad or some cut fruit at a meal, then you should be making a smoothie made from those ingredients. Soups can also deliver a cocktail of ingredients we might normally find in a salad. Bottom line get some color on your plate for a strong immune system and turn off your social media and screen time to get some sleep!

Finding the drive to get in the weight room to do in-season maintenance training after practices in heat is what really sets some athletes apart. For sure, staying hydrated at practice can dramatically improve your drive to lift in-season.

1) Rule number one is, don’t wait to drink until you are thirsty. Go into practice hydrated, and drink with routine intervals over the course of practice. Water will do the job leading up to practice, but I would plan on having a sports drink around during practice, in addition to water. The carbs in the sports drink will come in handy when it’s time to lift post-practice, and the salt and potassium will help you retain fluid balance in the heat.

2) A carb-filled snack item that digests fast towards the end of practice like a dried fruit, a banana or a cereal bar can help you find the drive to lift.

3) Motivated teammates can really help you find the drive to get in that weight room in-season, so find a good workout partner!

Lastly, you will want to eat as soon as you can after you lift. If logistics for getting home to eat are going to delay you for a couple of hours…

1) You will want to bring something with you to practice gapping up post-workout. Chocolate milk works great, or a protein-fortified bar – there are dozens of options in every grocery store now (20 g protein in a 70 g bar, for example).

2) Portable protein foods can work great post-workout as well, like string cheese, beef jerky or a good old PB&J.

3) When it comes to protein powders, make sure you use NSF Certified recovery beverages.

The bottom line is, don’t just show up to practice without some hydration and fueling solutions, and value the quality of your sleep and immune enhancing foods to maintain your health over the grind of the season.


Dave Ellis, RD, CSCS is a contributor to the USA Baseball Sport Development Blog, and is a veteran Sports RD with over three decades of experiencing working at the highest level of sports. Dave was the first president of the Collegiate and Professional Sports RDs Association (CPSDA) and is currently CPSDA’s Ambassador over all matter Food and Supplement Security related. Dave is also the Consulting Registered Dietitian for MLB/MLBPA and USA Baseball.