CSCS Nutrition Recommendations | Protein & Carbs for Athletes

Edited by: Danielle Abel

Nutrition recommendations for athletes are different than what lifestyle clients seeing a personal trainer might need. If you're curious about the key differences between athletes and personal training clients, keep reading. 

Nutrition for Performance

Nutrition for athletes is fairly straightforward, they need a lot of carbs! There's definitely more detail that we'll unpack in this article, including protein recommendations, but if you've ever wondered what the main focus for athletes should be, it's carbs. 

Carbohydrates, or carbs for short, serve as the main source of energy for athletes. Carbs are one of three macronutrients, along with protein and fats. Carbs are broken down into glucose and used to fuel metabolic processes that convert food to energy. Carbs can be broken down and used for energy anaerobically (fast glycolysis) and aerobically (slow glycolysis). 

However, glucose can also be made by the body, via a process called gluconeogenesis. However, consuming carbs provides a quick source of energy for sports movements for athletes and is overall more efficient. 

Before we dive further into carbs, you also need to know protein recommendations for athletes. 

How much protein do athletes need?

The amount of protein an athlete needs is probably based on the degree to which they break down muscle and other connective tissues like ligaments & tendons. 

Previously, the National Strength and Conditioning Association (NSCA), recommend separate protein intakes for endurance (1.0-1.6g/kg of body weight) & strength (1.4-1.7g/kg of body weight). However, that recommendation changed in late 2023/early 2024 when they standardized the protein range to 1.4-1.8g/kg of body weight for both endurance & strength athletes.  

Protein Ranges for Endurance & Strength Athletes

Here's an example, using an endurance athlete to help you calculate protein ranges: 

• 132lb female endurance athlete who's preparing for a half marathon 
  • First, you need to convert her weight to kilograms by taking her weight in pounds and dividing it by 2.2.
    • 132 / 2.2 = 60kg. 
  • Then, you need to find the lower and upper ranges for protein using the endurance athlete recommended g/kg ranges 
    • Lower range: 1.4g x 60kg = 84g of protein per day
    • Upper range: 1.8 x 60kg = 108g of protein per day

Using the values you calculated above, you might give her a protein recommendation of 84-108g of protein per day. Keep in mind, you may want to narrow the range a bit and use her current protein intake to help you determine what range would be best for her. 

You might be thinking, "Is it a bad thing to consume too much protein?" It's not that it's a bad thing; it's simply not as optimal if an athlete wants to be powerful. Athletes need plenty of protein, but they also need a large number of carbs to help them create fast & powerful movements repeatedly, and they can achieve this with carbs. 

How many carbs do athletes need?

Just like protein, recommended carb intake will vary based on the athlete's sport and position. For example, athletes who perform large volumes of training, endurance athletes for example, need more carbs than strength athletes to help them stay as powerful and strong as long as possible by fueling Type II muscle fibers with readily available glucose. 

Strength athletes need a large number of carbs as well, but since the movements of their sport come in bursts, with rest in between, they don't need as many carbs as endurance athletes. 

Keep in mind carb intake may also vary based on the season of training an athlete is in. For example, in the off-season, a strength athlete may have a greater focus on endurance training, so therefore they may require more carbs during this time compared to their in-season. 

Just like you do with training, it may be helpful to plan out athlete nutrition needs annually based on their training focus. 

In general, the NSCA recommends the following ranges for athlete carb intake:

• Endurance Athletes: 8-10g/kg of body weight
• Strength Athletes: 5-6g/kg of body weight

Carb Ranges for Endurance Athletes

Sticking with the 132lb female endurance athlete preparing for a half marathon, let's calculate how many carbs she would need to consume to fuel her training. 

• We can use the 60g of body weight that we converted from the protein recommendations above (if you skipped that section above, it explains how to convert pounds into kilograms).

From here, calculate the upper and lower ranges for carb intake for her. 

• Lower range: 8g x 60kg = 480g of carbs per day
• Upper range: 10g x 60kg = 600g of carbs per day

These ranges would apply during times when she is actively training for her race, and may not necessarily be what she needs to consume on cross-training days or rest days. 

Carb Ranges for Strength Athletes

For the 172lb male soccer midfield player we'll want to use the 5-6g/kg carb range for him. We converted his body weight into kilograms above (again scroll up to see how we did that if you skipped over it) and came up with 78.2kg. 

Just like we've been doing, we need to calculate the lower and upper ranges for carbs to provide to him. 

• Lower range: 5g x 72.8kg = 364g of carbs per day
• Upper range: 6g x 72.8kg = 437g of carbs per day

What about protein and carb timing?

Like with protein and carbohydrate ranges, timing also depends on the type of athlete you're working with. 

Endurance athletes who need to eat 4 hours before competition should eat 1 to 4 grams of carbs per kg of body weight and between 0.15 and 0.25 grams of protein per kg of body weight with that meal. 

• 132lb female endurance athlete training for a half marathon
  • Meal components 4 hours before competition: 
    • Carbs
      • 1g x 60kg = 60g of carbs
      • 4g x 60kg = 240g of carbs
    • Protein
      • 0.15g x 60kg = 9g of protein
      • 0.25g x 60kg = 19g of protein
  • A couple of example meals here:
    • A bowl of cereal with milk or choice + scrambled eggs
    • Toast with regular jam + greek yogurt 

Pre-training nutrition recommendations for strength athletes are not as clear as they are for endurance athletes due to limited research. However, we know that athletes who require strength, power, & speed will need carbohydrates to power working muscles.

• So it's probably safe to recommend at least 30-90g of carbs to strength athletes before training. 

There is research showing that strength athletes can decrease muscle protein breakdown by consuming at least 30-100g of carbohydrates post-training. 

Additionally, following resistance training, at least 20 to 25g of high-quality protein (protein containing all 20 amino acids) to stimulate muscle protein synthesis. 

• Older adults may need to consume as much as 40g post resistance training session to stimulate muscle protein synthesis.
• If exercise is performed in a fasted state (right away in the morning at greater than 3 hours after the last meal that contained protein), protein should be consumed within 30 minutes following the conclusion of a training session.

In general, recommending full meals to athletes that contain both protein & carbohydrate, along with fats, every 3 to 4 hours is likely a very good place to start from when it comes to nutrition recommendations for athletes. 

Support & Courses Available

Ready for more support to help you prep for the CSCS exam? Join our Facebook Group, “Strength and Conditioning Study Group,” here. Ready for even more? Our 24-module CSCS Prep Course has nutrition for maximizing performance in athletes completely laid out for you with even more content than what we’ve provided here, plus chapter quizzes to help you pass the NSCA exam; click the link here to check it out.