By mid-September, fall sports are in full swing. Football, soccer, cross-country, volleyball, field hockey, and marching band all mean long practices, early mornings, and weekend competitions. Somewhere in there, a teenager usually asks whether they should be taking something: a protein powder, a pre-workout, creatine, the energy drink their teammate swears by.
For parents and teen athletes, the honest answer is less exciting than the marketing but more useful. The vast majority of performance and recovery in adolescent athletes comes from three things: eating enough, drinking enough, and sleeping enough. A small number of nutrients are worth watching. A larger number of products are worth avoiding. Here is how to sort them.
Start With Fuel: Most Teen Athletes Under-Eat
Teenagers are still growing, and a growing body that also trains hard every day needs a lot of energy. Many teen athletes, especially those in sports where weight or appearance gets attention (cross-country, dance, wrestling, gymnastics), simply do not eat enough to cover both.
Chronic underfueling can lead to fatigue, stalled progress, frequent injuries, and, in girls, missed or irregular periods. Sports medicine groups call this relative energy deficiency in sport. Missed periods in an athlete are not a sign of fitness; they are a reason to see a doctor.
Practical fueling for fall sports:
- Three meals plus snacks, with a snack 1-3 hours before practice (a sandwich, yogurt and fruit, or a granola bar and banana).
- A recovery snack or meal within a couple of hours after training that includes carbohydrates and protein, such as chocolate milk, a turkey wrap, or leftovers.
- Carbohydrates are not the enemy. They are the main fuel for high-intensity sports.
- Protein from food. Active teens often do well at roughly 1.2-1.6 g/kg of body weight per day, which most reach with regular meals. Protein powder is a convenience for busy schedules, not a requirement.
Hydration for Hot Early-Season Practices
September practices can still be hot, and teens do not always drink until they are already behind. For most practices under an hour, water is enough. Sports drinks with carbohydrates and sodium make sense for sessions longer than 60-90 minutes, two-a-days, heavy sweaters, or high heat.
A simple check: pale yellow urine generally means adequate hydration. Weighing before and after practice can also show how much fluid a teen typically loses. Our electrolytes guide explains when sodium and potassium actually matter and when a plain water bottle does the job.
Heat illness is a real risk early in the season. Dizziness, confusion, nausea, or stopping sweating during hot practices are signs to stop, cool down, and get medical help.
Nutrients Worth Watching
Iron
Iron is the nutrient most likely to run low in teen athletes, especially menstruating athletes, distance runners, and those who eat little or no meat. Low iron stores can cause fatigue and poorer endurance well before full anemia shows up.
- RDA (ages 14-18): 15 mg/day for girls, 11 mg/day for boys.
- Test first. A ferritin and complete blood count through the pediatrician tell you whether iron is actually low. Supplementing without a reason can cause constipation and stomach upset, and iron overload is a risk for some people.
- Upper limit: 45 mg/day from supplements for teens, unless a doctor prescribes more for a diagnosed deficiency.
- How to take it: Many take iron with a vitamin C source and away from dairy, calcium supplements, coffee, and tea. Some doctors recommend every-other-day dosing for better absorption and fewer side effects.
- Storage: Keep iron supplements locked away from younger siblings. Accidental iron overdose is dangerous for small children.
Our iron supplement profile covers forms and dosing in more depth.
Vitamin D and Calcium
Teens build most of their lifetime bone mass during these years, and stress fractures are common in some fall sports, particularly running.
- Calcium: 1,300 mg/day for ages 9-18. Three to four servings of dairy or calcium-fortified alternatives covers most of it. If a supplement fills a gap, keep single doses to about 500 mg for better absorption.
- Vitamin D: 600 IU/day RDA, with an upper limit of 4,000 IU/day for ages 9 and up. As days shorten and indoor time increases, levels can drift down. A blood test can guide whether a supplement is needed, especially for athletes with darker skin, those who train indoors, or those with a stress fracture history.
A Basic Multivitamin?
A standard multivitamin is not necessary for a teen who eats a reasonably varied diet. It can be a reasonable safety net for picky eaters, vegetarian or vegan athletes, or teens with food allergies that restrict whole food groups. Choose one without megadoses, and count its iron and vitamin D toward the daily totals above.
What to Skip
This is where the supplement aisle and teen locker rooms tend to cause trouble.
Pre-workout powders. These often contain large or unclear doses of caffeine and other stimulants, sometimes in proprietary blends. Stimulant-heavy products have been linked to racing heart, anxiety, and sleep problems, and some have been found to contain undeclared or banned ingredients.
Energy drinks. Pediatric groups advise that energy drinks have no place in children’s and teens’ diets. If a teen uses caffeine at all, a commonly cited ceiling for adolescents is about 2.5 mg per kg of body weight per day, roughly 150 mg for a 60 kg (132 lb) teen. That can be less than a single large energy drink. Caffeine after mid-afternoon also cuts into sleep, which costs more performance than it adds.
Creatine. Creatine is well studied in adults, but research in adolescents is limited, and major pediatric organizations advise against performance-enhancing supplements, including creatine, for athletes under 18. This is a question for the teen’s doctor, not the team group chat.
Testosterone boosters, fat burners, and “muscle builders.” These are among the product categories most often found to contain hidden drugs, stimulants, or banned substances. For a competing athlete, a positive drug test is a real possibility. For a still-developing body, the risks are not worth it.
Anything a coach or teammate hands out unlabeled. If you do not know exactly what is in it, do not take it.
If a teen does use a protein powder or other supplement, choose one certified by a third-party program designed for athletes, such as NSF Certified for Sport or Informed Sport. These programs screen for banned substances. Our guide to third-party testing seals explains what each certification does and does not guarantee.
Sleep: The Underrated Performance Tool
Teenagers generally need 8-10 hours of sleep a night, and most active teens fall short, especially once early practices, homework, and screens compete for time. Insufficient sleep is linked to slower reaction times, poorer mood, and higher injury risk in young athletes.
Melatonin is not a routine fix for a packed schedule. Doses in over-the-counter products are often much higher than needed, and a pediatrician should weigh in before a teen uses it regularly. Consistent bedtimes, a cool dark room, and phones out of the bedroom do more.
A Quick Checklist for Parents
- Is your teen eating breakfast and a pre-practice snack?
- Do they bring a water bottle and drink during practice?
- Has anyone checked iron and vitamin D, particularly for a runner, a vegetarian, or an athlete with persistent fatigue?
- Are they getting at least 8 hours of sleep most nights?
- Do you know what is in the tub or can they are using?
For a broader look at nutrition during the teen years, see our overview of supplements for teenagers.
Bottom Line
Fall sports put real demands on growing bodies, but the answer is rarely a supplement. Enough food, enough fluids, and 8-10 hours of sleep do most of the work. Iron, vitamin D, and calcium are worth checking, ideally with a blood test and a pediatrician’s input, before supplementing. Pre-workouts, energy drinks, creatine, fat burners, and testosterone boosters are best left on the shelf for athletes under 18.
This article is for educational purposes only and is not medical advice. Talk with a pediatrician or healthcare provider before a teen starts any supplement, especially if they are pregnant or nursing, take medication, or are managing a health condition.