Meal Timing for a Cardio Workout

Regardless of the number of cardio sessions you do or the distance you log, nutrition plays a key role in not only how you perform, but also how you feel. Exercising without eating enough is like burning the candle at both ends—it's not efficient.

Instead of spinning your wheels and going nowhere, take a few moments to plan out your pre- and post-workout nutrition and hydration plan so you can make the most of your cardio workouts. Here is what you need to know about meal timing and cardio workouts.

Before Your Workout

Whether you eat before your cardio workout is dependent upon the type of exercise you're going to do and the duration. A short 60 minutes (or less) low-intensity workout may not need additional fuel beforehand as what's stored in the muscle and liver should provide you with enough energy if you ate up to 4 hours prior to exercising.

On the other hand, any endurance exercise longer than 60 minutes requires a pre-workout meal or snack and continuous refueling during exercise to help prevent dips in performance and energy. If you're a competitive athlete, the timing of your pre-workout nutrition should be more precise.

You may need up to 1 to 4 grams of carbohydrates per kilogram of weight before training with up to 12 grams of carbohydrates per kilogram of weight in between workouts.

Fueling too close to your workout—such as within 75 minutes—poses a risk of rebound hypoglycemia. If this is an issue, fueling with a bar or gel within 15 minutes of exercising can be helpful to prevent hypoglycemia. If you're someone who has difficulty eating so close to physical activity, then spacing it out within the span of 4 hours prior to your workout is perfectly fine. Overall, pre-workout needs are individualized.

Carbohydrates are the most important factor in endurance. However, if consumption is less than 1.2 grams per kilogram of weight per hour, then protein can help with glycogen recovery.

Food

Quick snacks are perfect pre-workout. They're convenient, easy to prepare, and easy to consume wherever you are. High glycemic index foods are recommended.

Hydration

Drinking water before a cardio workout is part of preventing dehydration while optimizing performance. Being adequately hydrated is essential for physical performance and to reduce stress on the cardiovascular system and risk of injury.

Starting a workout optimally hydrated is important to prevent dehydration. The night before training, consume 500 milliliters of water or sports drink. Another 500 milliliters upon waking, and then another 400 to 600 milliliters of water or sports drink 20 to 30 minutes before your workout.

To assess whether you're hydrated to begin with, you can monitor the color of your urine. Yellow or dark amber urine is a good indicator that you need to be drinking more water. If your urine is light in color, you're well hydrated!

During Your Workout

There are only a handful of scenarios where eating during your cardio workout is helpful, namely ultra endurance events like an Ironman, triathlon, or any activity covering a greater distance than a marathon. Even running a marathon may require use of gels or other fuel sources.

According to the International Society of Sports Nutrition position on nutrient timing, any high intensity activity greater than 60 minutes would benefit from fueling with 30 to 60 grams of carbohydrates per hour in a 6 to 12 fluid ounce solution containing 6% to 8% carbohydrates with electrolytes for the duration of the activity. The addition of protein is helpful to increase performance, maintain normal blood sugar levels, prevent muscle damage, and facilitate energy production.

Food

Fueling up (aside from a water break) during a long cardio workout must be convenient and easy to store. Look for practical options that can be carried in your pocket or waist pack.

Remember to try your intra-workout fuel sources on a training day before your event. That way you can eliminate anything that is difficult to race with or causes GI upset. Doing so can ensure you do not have any disruptions on race day.

After Your Workout

Fueling up after a workout is just as important as your pre- and intra-workout nutrition. The post-workout meal can help restore glycogen (carbohydrate) stores and speed up recovery.

While timing may not be detrimental (the body absorbs nutrients no matter how long you wait to eat), the sooner you eat the quicker your body can begin the recovery process. Shoot to consume 20 to 40 grams of protein every 3 to 4 hours to meet between 1.4 to 2.0 grams of protein per kilogram of weight per day.

Protein intake may be necessary if the workout wasn't fueled by greater than 1.2 grams of carbohydrates per kilogram of weight per hour. Within 4 to 6 hours of working out, aim for 1.2 grams of carbohydrates per kilogram of weight per hour.

Food

While protein shakes are convenient, they're not the only option when it comes to post-workout fuel. Get creative with your post-workout meal and experiment with a variety of quick and easy ideas with a concentration of carbohydrates.

Hydration

Sweat loss can account for 3 to 4 liters of water per hour during a cardio workout. Working out in a hot, humid environment or at a high altitude will increase this number. The effects of water loss can be felt at just 1%. For that reason it is essential to rehydrate after a workout.

The primary goal is not to lose any water weight while working out. However, if it does happen, it is best to measure your weight before and after your work out. A good rule of thumb is to drink 16 to 24 ounces of water for every pound lost. Finally, never rely on your thirst because it's a response that occurs when you already lost a significant amount of fluids through sweat.

Rest Day Nutrition

Taking rest days can make you a better athlete, or just make you better at the workouts you enjoy. Rest days are important for muscle recovery, energy replenishment, and to prevent overtraining and injury.

What you eat on rest days is just as important as the rest day itself. A menu that promotes recovery and nourishes the body should include sufficient calories, lean protein (to promote muscle recovery), and carbohydrates (replenishes glycogen stores). Skimping out on calories can leave you weak and sluggish at your next workout, so make sure you eat enough.

A Word From Verywell

Cardio workouts require pre- and post-workout fuel just the same as resistance training, especially if your workouts are lasting longer than 60 minutes. Without proper nutrition and hydration before, during, and after a long cardio workout you increase your risk of injury and overtraining.

If you have any questions or are having trouble putting together a fueling plan, talk to a healthcare provider or registered dietitian. They can help you discover what works for you.