Nutrition for the Athlete

By: Michelle Miller, Clinical Nutritionist & Rachel Naar, Registered Dietitian

What to Eat and How to Eat It


Muscle glycogen is used the most rapidly during the first stages of exercise. And you guessed it, you’re going to need to make sure you’ve got an adequate supply. This is the only nutrient that can be used for anaerobic energy production (to help promote strength, speed, and power) through weight-bearing exercises, and creates energy for muscle contractions up to 3x faster than fat. (Take THAT ketogenic diet.)

There is a strong association between lack of glycogen (the storage form of glucose which is derived from carbohydrates) and fatigue.

What is the role of carbohydrates during an activity?

Carbs power the contractile proteins of the muscle and fuel the brain and the central nervous system.

So how much do you need?

Well, that depends on YOU! We assess carbohydrate needs based on age, medical state, and physical activity level. Specific needs vary with the type of exercise, the intensity of exercise, and duration.

Training Day Carbs

  • 3-5g/kg for low intensity (shorter training days)
  • 8-12g/kg for very high intensity

Example: If you are 150 lbs, you are roughly 68 kg. If it is a light training day you may consider 4g/kg. So 4g/68kg= ~272g of carbohydrates.*

(*) note: ballpark, always consult with a nutritionist, specifically someone well-versed in sports nutrition.

Before the event

  • At some point between 1-4 hours before your event, top off stores with 4g/kg of carbohydrates.

Example: If you are 150 lbs, you are roughly 68 kg. If this is your event day, you may consider 4g/kg. So 4g/68kg= 272g of carbohydrates before your race.

During the event

  • 90g/hour (this will not necessarily be specific to your gender or size).

After the event

  • Every hour, for 4 hours following your race, be sure to get 1-1.2g/kg of carbohydrates.

Your body needs carbs; this is not the time for a low carb diet!

Carbohydrates and Nutrition for the Athlete at Physio Logic in Brooklyn NY
The above picture notes what contributes to an average ~15g of carbohydrate.


The RDA recommends 0.8g/kg of protein per day for healthy individuals, but studies have shown that protein requirements are elevated for athletes. The ADA/ACSM recommends 1.2-2.0g/kg* for endurance athletes.
This range is necessary to support metabolic adaptation, repair, remodeling, and for protein recovery.

The ADA/ACSM recommendations encompass most training regimes, however, requirements can change based on “trained” status (experienced athletes requiring less protein), exercise intensity, carbohydrate availability, and total energy intake.

This requirement can be met by diet alone! Seek to distribute high-quality protein throughout the day and/ or following key training sessions to the tune of 0.25-0.3g/kg or roughly ~15-25g of protein. Research shows increases in strength and muscle mass with immediate post-exercise ingestion of protein.

Ex. If you are 150 lbs, you are roughly 68 kg. Total protein needs throughout the day are between 81.6g-136g. Spread throughout the day and following key exercise bouts that translates into = 20.4g to 27.2g spread over 4 or 5 meals.

It’s important to consume high-quality dietary proteins. According to the ADA/ ACSM high-quality protein sources include milk-based proteins due to their high leucine content and the digestion and absorption kinetics of branched-chain amino acids in fluid-based dairy foods. However, if milk-based products don’t work for you, below is a list of high-quality protein sources:

Proteins and Nutrition for the Athlete at Physio Logic in Brooklyn NY


Fat intake depends on exercise intensity, duration, and carbohydrate stores/intake during exercise. Higher carbohydrate and protein intake typically means lower fat intake. Severe restriction of fat intake is also not recommended. For a generally healthy individual, fat should make-up 20-35% of your total caloric intake. To achieve proper fat intake, athletes should look at roughly ~1g/kg daily.

Fats and Nutrition for the Athlete at Physio Logic in Brooklyn NY

Omega-3 Fatty Acids

  • Research has shown that Omega-3 Fatty Acids, found in both plants and fish, are beneficial to endurance athletes.
  • Omega-3s are important to immune function, modulating inflammation and recovery.
  • Endurance athletes that supplemented with Omega-3s experienced decreased muscle soreness, reduced swelling, and in some research decreased recovery time.
  • Good animal sources are sardines, salmon, eggs, cod liver oil, tuna.
  • Aim for between 1000mg-2000mg/ day.
    • One serving of fatty fish every other day will get you to that goal, as will the appropriate intake of plant based Omega-3s or a high-quality fish oil supplement.

In conclusion…

  • During a time of intense training, you must adequately fuel your body.
  • Carbohydrates will make up the majority of your diet, followed by protein, and then fat.
  • Be mindful of the different intake amounts of carbohydrate/protein/fat depending on your energy expenditure (light training days vs. longer race day/ marathon).

Be sure to consult with a nutritionist that has a specialty in sports nutrition.

At PhysiologicNYC, Our priority is your well-being,

Schedule an appointment with the Clinical Nutrition Department by filling out the form below or calling now.

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