What Does a Sports Dietitian Do—and Do You Need One?

Feb 3

If you're training regularly, preparing for a competition, or trying to perform better in the gym, simply "eating healthy" often isn't enough. Fueling for athletic performance requires much more than just eating more fiber or protein, but with so much conflicting information online, it can be hard to know where to start. That's where a sports dietitian comes in.

While general nutrition advice can work for the average person, athletes have unique physiological demands related to energy availability, recovery, hydration, gastrointestinal issues, and performance outcomes. A sports dietitian specializes in helping athletes fuel strategically and goes beyond simply "eating well."

Sports Dietitian vs. General Dietitian: What's the Difference?

First, let's clear up a common misconception: dietitian and nutritionist are not interchangeable terms. Unlike the title nutritionist, which is unregulated in many states and does not have a universal governing body or standardized set of education requirements, registered dietitians must complete rigorous postgraduate education, supervised clinical practice, and credentialing requirements to provide evidence-based nutrition care. A registered dietitian is a medically credentialed nutrition professional qualified to provide medical nutrition therapy who:

Is a member of the multi-disciplinary medical team providing thorough care to athletes (alongside Certified Strength & Conditioning Specialists, certified athletic trainers, physical therapists, physicians, and sports psychologists).
Reduces liability for the athlete and the sports organization through validated credentials and their knowledge of medical conditions, medications, etc. that must be considered when providing safe recommendations on nutrition and supplements.

If you're serious about optimizing every aspect of your health to give yourself the best shot at advancing in your sport, if your million-dollar professional sports contract depends on your performance, or simply, if you're paying for the help, you probably want to work with the credentialed expert.

All registered dietitians (RDs/RDNs) are qualified nutrition professionals trained in medical nutrition therapy, behavior change strategies, and evidence-based practice. But a sports dietitian has additional expertise in exercise physiology and performance nutrition.

While a general dietitian may help with chronic disease management or general healthy eating habits, a sports dietitian applies nutrition fundamentals through a performance lens. That includes:

Periodized fueling strategies that align with your specific training cycles
Carbohydrate timing for endurance athletes
Recovery nutrition optimization
Hydration and electrolyte planning
Preventing underfueling and energy deficiency
Assessment of all sports supplements and fortified foods for safety, efficacy, and quality to protect the athlete’s eligibility and health
Assessing and monitoring of body composition and weight in a way that prevents eating disorder and body image issues

In short, a general dietitian helps support overall health, while a sports dietitian helps you optimize how you perform in your chosen sport. Many sports dietitians also hold specialized credentials, such as the Certified Specialist in Sports Dietetics (CSSD), which means the dietitian also holds a board certification with specific RD eligibility and practice hour requirements, indicating that they have advanced training in sports nutrition.

Who Can Benefit From Working With a Sports Dietitian?

You don't need to be an Olympic athlete to benefit from sports nutrition support. Many recreational and competitive athletes alike often see meaningful improvements in their performance after working with a sports dietitian.

Endurance Athletes

Runners, cyclists, triathletes, and swimmers place high demands on glycogen stores and recovery systems. A sports dietitian can help with fueling for longer events, preventing energy crashes, managing GI symptoms, and planning recovery nutrition. Many endurance athletes unintentionally underfuel, which can impair performance and increase the risk of injuries.

Team Sport Athletes

Athletes in team sports like soccer, hockey, basketball, or volleyball often juggle intense practices, travel schedules, and competition demands. A sports dietitian can help these types of athletes maintain consistent energy levels, recover between games and tournaments, and navigate busy training schedules.

Strength and Power Athletes

Weightlifters and CrossFit athletes often aim to improve muscle mass and strength. Nutrition strategies for these athletes include protein distribution and timing, making weight safely (when required), and supporting training volume without burning out.

Active Individuals and Recreational Athletes

Even weekend runners or gym-goers can benefit from performance-focused nutrition. If you exercise regularly and feel constantly fatigued, sore, or stuck in a performance plateau, nutrition may be the missing piece of the puzzle.

Athletes At Risk of Underfueling

Athletes with disordered eating habits, compromised bone density, frequent injuries, and/or amenorrhea (essentially, those with any risk signs for RED-S or underfueling complications) can benefit from working with a sports dietitian to ensure they're fueling appropriately for their training.

Athletes At Different Life Stages

Athletes or active individuals at different life cycles or stages of their athletic development, such as adolescents, college athletes transitioning to pro athletes, athletes still growing and developing (pediatric/teen athletes), pregnant/lactating individuals, pro athletes transitioning to retirement/general activity, mature adults, and the elderly, can all benefit from working with a sports dietitian who can customize their nutrition plan based on their life stage.

People Who Work With Athletes

Coaches, CSCS, and team managers can benefit from working with a sports dietitian to learn how to integrate specialized medical nutrition therapy into their program to optimize nutrition practices in their athletes, increase the safety and efficacy of their nutrition practices, and reduce their organization’s liability. Having non-credentialed individuals consult with athletes on anything beyond basic nutrition advice can cause serious complications, especially when pre-existing medical conditions or medications are not considered.

Common Reasons to Work With a Sports Dietitian

There are many reasons a person may choose to work with a sports dietitian, but here are some of the most common reasons I see in my practice:

Achieving consistency in your workouts & events: If your energy levels, exercise efficiency, or overall experience during workouts feel unpredictable, nutrition may be one contributing factor. A sports dietitian can help identify fueling, hydration, recovery, and gastrointestinal factors that may be affecting consistency. Many athletes report feeling more prepared and confident in their fueling strategy after working with a sports dietitian.
Fueling for performance: Many athletes either underfuel or mistime their nutrition around workouts. Working with a sports dietitian can teach you how to time your carbohydrate, protein, and hydration intake while optimizing your performance.
Gastrointestinal issues during exercise: GI symptoms are extremely common in athletes, particularly in runners and endurance athletes. A sports dietitian can help identify triggers and develop gut-training strategies to help minimize GI issues during longer training sessions or races.
Relative energy deficiency in sport (RED-S): RED-S is a syndrome of impaired physiological and/or psychological functioning caused by low energy availability—when dietary energy remaining after exercise is insufficient to support normal body functions. It can affect athletes of all genders, body sizes, ages, and sport types. Potential signs of RED-S include recurrent bone stress injuries (and frequent injuries in general), chronic fatigue, reduced training response, frequent illness, mood changes, declining performance, or loss of menstrual cycle. A sports dietitian plays a key role in restoring adequate energy availability and supporting safe continuation of training when appropriate.
Performance plateaus: If training volume is increasing but your performance is lagging, nutrition may be the limiting factor. Common nutrition-related performance barriers include inadequate carbohydrate intake, poor recovery fueling, or chronic dehydration. Small adjustments to these variables often help you break out of a performance plateau.

Sports Dietitian Support for GI Symptoms During Exercise

Exercise-related GI symptoms — including urgency, cramping, nausea, reflux, bloating, or diarrhea — can interfere with training and race-day performance. A sports dietitian can help assess likely contributors such as pre-exercise meal timing, carbohydrate type and dose, hydration practices, caffeine, fiber and fat intake, stress, and the demands of the event itself. For endurance athletes, this may include an individualized gut-training plan that is practiced in training rather than tested for the first time on race day.

Clinical Note: persistent, severe, or new symptoms — especially bleeding, unexplained weight loss, or symptoms outside exercise — warrant medical evaluation.

What to Expect When Working With a Sports Dietitian

Working with a sports dietitian is highly individualized, and a typical appointment goes far beyond simply reviewing what you ate yesterday. You can expect discussions about:

Training and competition demands: This includes training frequency, intensity, competition schedule, and overall performance goals. Your dietitian uses this information to tailor fueling, hydration, and recovery strategies to the demands of your sport and training cycle. When nutrition is a limiting factor, an individualized plan may support more consistent energy, recovery, and training quality.
Nutrition assessments: This may include typical daily intake, meal timing, supplement use, hydration habits, and travel or scheduling challenges. The assessment helps identify potential nutrition-related barriers and opportunities. Depending on your goals, health history, training demands, and baseline intake, targeted changes may support body-composition goals, training capacity, recovery, and day-to-day energy.
Health and injury history: Sleep, stress, menstrual health, injury history, and digestive symptoms all influence performance nutrition planning. Addressing these factors can help reduce injury risk, improve recovery, support long-term health, and ensure your body is able to consistently perform at its best.
Goal setting and strategy development: Rather than a rigid meal plan, most sports dietitians provide flexible strategies, such as fueling frameworks, pre- and post-workout meal ideas, race-day nutrition plans, and recovery targets. Strategies will be refined in follow-up sessions. This gives you a clear, practical roadmap for achieving your goals while building habits that are sustainable long after the season ends.
Anticipation of challenges with preventive plans in place: Years of experience working with athletes of all levels across all sports allow me to anticipate challenges and setbacks before they occur and prepare my patient-athletes for them, both mentally and through preventive action plans. When stakes and nerves are high, there’s nothing more calming than knowing that you can trust the experienced members of your team to help you quickly pivot in a way that makes a potential disaster just a blip on the radar. This helps minimize disruptions to training and competition, allowing you to stay focused, confident, and prepared when challenges inevitably arise.

How to Find a Qualified Sports Dietitian

Not all dietitians are trained in sports performance. Here's what to look for when trying to find a sports dietitian:

Registered dietitian credentials: Ensure the provider is a registered dietitian (RD or RDN).
Sports nutrition experience: Look for experience working with athletes, or a background in exercise or performance nutrition. While not required, finding a dietitian with their CSSD credential is an added bonus.
Sport-specific experience: A dietitian familiar with your sport will better understand the challenges of race fueling, tournament schedules, and weight-class requirements.
Membership in professional sports nutrition organizations: Dietitians who are members of the ASPDA or the Sports and Human Performance Nutrition DPG within the Academy of Nutrition and Dietetics demonstrate a commitment to leadership responsibilities, research, ongoing education, and active involvement in the sports nutrition professional community.
Evidence-based approach: Be cautious of providers promoting extreme diets and unnecessary supplement stacks.

Final Thoughts

A sports dietitian helps bridge the gap between training hard and performing well. Whether you're chasing a personal best, recovering from an injury, or simply trying to feel stronger during your workout, nutrition plays a key role.

Working with a sports dietitian isn't just for elite athletes. I've worked with many people who want their nutrition to actively support their performance, recovery, and long-term health.

If you're looking for support with running nutrition, my Fuel To Train program offers tiered nutrition and hydration plans tailored to your unique needs. These plans are designed to help you understand how proper fueling can support your training, race day, and recovery.

Lauren Cornell, MS, RD, CSDH