Dietitians and nutritionists often receive questions about pre- and post-workout nutrition. While answers can vary based on individual needs and activities, there are common guidelines. Pre-workout snacks should be enjoyable and beneficial, providing energy and preparing muscles for the exercise ahead. Post-workout nutrition is essential for refueling, recovery, and muscle growth.
Eating the right foods before and after workouts is crucial because it provides the optimal fuel for the mitochondria, the powerhouses of your cells, to produce energy. To function efficiently, the mitochondria need both carbs and fats as fuel. When the mitochondria can easily switch between burning carbs or fats, depending on their availability and your body’s needs, it makes you metabolically flexible.
This has many benefits, such as enhanced athletic performance, muscle mass growth, and better body composition.
Exercise is a cornerstone of a healthy lifestyle, providing numerous benefits beyond physical appearance. Regular physical activity improves cardiovascular health, enhances mood, supports weight management, and strengthens muscles and bones. Understanding the different types of exercise and how they impact our bodies is crucial for optimizing our workout routines and nutritional strategies.
Exercise can generally be categorized into two main types: aerobic and anaerobic workouts. Each type serves different purposes and offers distinct benefits.
Aerobic exercise, also known as cardio, involves sustained, rhythmic activities that increase your heart rate and breathing. These workouts rely on the continuous use of oxygen to generate energy through aerobic metabolism. During aerobic exercise, the body uses carbohydrates and fats as the primary energy sources, converting them into ATP (adenosine triphosphate) with the help of oxygen. Fat is typically used as fuel by the mitochondria during prolonged low-intensity exercise like walking. Common examples of aerobic exercises include:
Aerobic workouts are typically low to moderate-intensity activities performed over an extended period. They effectively improve cardiovascular health, enhance lung capacity, and boost endurance.
Anaerobic exercise consists of short, intense bursts of activity where the oxygen demand exceeds the supply available. These workouts rely on glucose stored in the muscles as glycogen. During anaerobic metabolism, glycogen is broken down into glucose, which is then used to produce ATP (adenosine triphosphate) through glycolysis. This process does not require oxygen and results in lactate production, which can accumulate in the muscles and cause the characteristic "burn" associated with intense exercise. Common examples of anaerobic exercises include:
Anaerobic workouts are typically high-intensity activities performed in short durations. They are effective for building muscle strength, power, and muscle mass and improving overall body composition.
Both aerobic and anaerobic exercises contribute to various aspects of health and well-being. Here’s how they impact key areas:
Aerobic exercise is particularly beneficial for cardiovascular health. It strengthens the heart muscle, improves blood circulation, and lowers blood pressure. Regular aerobic activity can reduce the risk of heart disease, stroke, and hypertension.
Anaerobic exercise also supports cardiovascular health by enhancing the efficiency of the heart and lungs during high-intensity efforts. This training can improve the body’s ability to manage and recover from intense physical exertion.
Mitochondria play a crucial role in energy production. Both aerobic and anaerobic exercises stimulate mitochondrial biogenesis, increasing the number and efficiency of mitochondria in the muscles [1]. This leads to better energy production, improved endurance, and overall cellular health. Your muscles are packed with mitochondria. So, the more muscle mass you gain through anaerobic training, the more mitochondria you’ll have. This translates to increased fat burn at rest and a quick shift to carb burn when you need a little boost.
Aerobic exercise primarily aids in fat loss by increasing energy expenditure. With the appropriate diet, it can help you achieve a leaner body composition.
Anaerobic exercise, particularly resistance training, is vital for building and preserving muscle mass. It promotes a higher resting metabolic rate, aiding long-term weight management and body recomposition.
Exercise, in general, is known to enhance mood and reduce symptoms of depression and anxiety. Aerobic exercise releases endorphins, often referred to as "feel-good" hormones, which can improve mood and promote relaxation.
Pre-workout nutrition is important to ensure the body has enough energy to perform effectively, especially during high-intensity workouts. Consuming carbs before exercising helps balance your glycogen stores to maximize performance, delay fatigue, and improve endurance. When glycogen is depleted, your mitochondria won't have the reserves to provide energy boosts, leaving you feeling sluggish. Carbohydrates provide the necessary fuel for the body, while protein helps prepare the muscles for the stress of training, reducing the risk of injury and enhancing muscle repair and growth.
Timing: Eat 1 to 4 hours before exercising to avoid gastrointestinal discomfort and performance issues.
Carbohydrates: Essential throughout the workout, breaking down into glucose for energy.
Protein: Small, easy-to-digest portions to help repair muscle micro-tears.
Hydration: Proper hydration with 250-350mL of water pre-workout and 20-30mL in small sips during exercise.
Post-workout nutrition directly impacts recovery, muscle growth, and overall performance. During exercise, especially intense or high-endurance sessions, the body’s glycogen stores are depleted. Consuming carbohydrates post-workout is essential to replenish glycogen stores, ensuring the body has enough energy for subsequent activities. Additionally, protein intake is vital for repairing and rebuilding muscle fibers that break down during exercise. For workouts that are extremely energy-demanding, replacing expended energy with fat is important to restore energy balance. Proper fueling helps avoid muscle breakdown, reduces the risk of fatigue and injury, and supports continuous improvement in fitness and strength.
Lumen supports users with finding the proper workout nutrition. By taking measurements before and after a workout, Lumen can help you determine the right nutrition based on the workout type and measurement results. For anaerobic workouts, starting with a high Lumen level is best, ensuring you have enough energy for the workout.
Conversely, aerobic workouts can be performed starting with a lower Lumen level, depending on the purpose. If the aim is to reach fat burn quickly and for a prolonged period, you can start the workout with a lower Lumen level and may not need to fuel up beforehand. However, if you plan to engage in high-endurance training, eating some carbs before the workout can be beneficial.
After a workout, post-workout breath measurements will help determine how many macros you should consume to best recover from your session.
Macros: 17g fat, 54g carbs, 16.5g protein
Macros: 11g fat, 50g carbs, 20g protein
Whole-grain toast with avocado and egg
Macros: 22g fat, 30g carbs, 15g protein
Banana and almond butter
Macros: 9g fat, 34g carbs, 3g protein
Pre-workout energy balls
Macros: 12g fat, 30g carbs, 6g protein
Grilled chicken with quinoa and vegetables
Macros: 10g fat, 45g carbs, 30g protein
Salmon with sweet potato and asparagus
Macros: 18g fat, 30g carbs, 30g protein
Turkey and avocado wrap
Macros: 18g fat, 30g carbs, 28g protein
Egg and veggie scramble
Macros: 15g fat, 30g carbs, 20g protein
Greek yogurt with honey and berries
Macros: 4g fat, 25g carbs, 15g protein
Apple slices with peanut butter
Macros: 250 calories, 16g fat, 28g carbs, 6g protein
Post-workout smoothie
Macros: 10g fat, 35g carbs, 10g protein
Cottage cheese with pineapple
Macros: 200 calories, 4g fat, 30g carbs, 12g protein
Hummus with carrot and cucumber sticks
Macros: 200 calories, 10g fat, 25g carbs, 5g protein
Ensure meals and snacks include carbohydrates to maintain energy levels and prevent the body from resorting to gluconeogenesis, the synthesis of glucose from non-carbohydrate sources, which can elevate Lumen levels.
You can adjust the amount of workout carbs based on your energy levels and hunger cues. Listen to your body to find the right balance for optimal performance and recovery.
Whether you’re engaged in aerobic or anaerobic exercise, knowing how to fuel your body before and after your workout is vital to get the most out of your session and recover properly after.
Pre- and post-workout nutrition is the answer to unlocking more energy to power through your training, build muscle, improve body composition, and prevent injury. Get into the habit of measuring your metabolism before and after your workout to figure out how to best fuel your own body.
[1] Eluamai, A., & Brooks, K. (2013). Effect of aerobic exercise on mitochondrial DNA and aging. Journal of Exercise Science & Fitness, 11(1), 1–5. https://doi.org/10.1016/j.jesf.2013.03.003
Ulrike is the Head of Nutrition at Lumen. She has a BSc in Human Nutrition from the University of Hamburg, Germany, and an MSc in Nutrition Sciences from the University of Halle, Germany. She is also a Registered Dietician (RD) through the German Nutrition Association. Ulrike has been widely published as an expert and opinion leader on metabolic health on the Telegraph, NetDoctor, the Express, and other media outlets.