Any strenuous exercise depletes your body. It is during the recovery phase that you can reap the benefits of your workout.
A huge part of this replenishment involves nutrition. Learning what to eat after cardio can make sure that you are rewarded for every ounce of effort you put into your workout.
There are different types of cardio. Keep in mind that anything that raises your heart rate—from logging an hour on a treadmill to doing hill sprints to a fast walk – is cardio in some form. If you do ten minutes of hill sprints you’re going to burn more energy and calories than you will walking. When this is the case, refueling is going to be more urgent. It will be important for you to learn to trust your hunger. When your body is screaming that you need to eat, you need to listen to it. Optimal results will come from knowing how to eat.
30-45 minutes of low-level cardio is probably not going to be enough to completely deplete your energy stores. Your focus in the aftermath of any cardio is two-fold: replenish the fluids you have lost, best done in the form of 8-16 ounces of water, and eat a post-workout meal within 30-60 minutes of finishing your workout. In a 2015 issue of Environmental Nutrition, dietician Molly Kimball recommends roughly a 3:1 ratio of carbohydrates to protein. The protein will help rebuild your muscles, and the carbohydrates will replenish your energy stores.
If you perform a more intense cardio session (or significantly longer, such as distance running) the philosophy remains the same, but you may need to increase the number of calories, carbs, and protein in your post-workout meal according to how much energy you expended, your performance, and your bodyweight. Stick with the 3:1 ratio of carbs to protein, unless your performance or results start to drop to an undesirable level. When that happens, maintain the intensity of your workouts, but add 300 clean calories per day to your total and see if it restores your energy and improves your results.
The post-workout whey protein shake is a staple of modern-day training. Because it is recommended that you eat within 30-60 minutes after a workout, shakes are obviously convenient. Protein quality is not all the same, however. When choosing a protein for your post-workout meal, one of the most important factors is the protein’s biologic value (BV).
BV refers to the amount of protein that your body actually uses after consumption. For instance, a protein source with a BV of 100 means that 100% of it was used and absorbed by your body. You got the maximum benefit out of that meal, in terms of protein. A 2015 study in the Carpathian Journal of Food Science & Technology found that a whey protein shake, consumed after a workout, has great value, because most whey shakes fall within the 90-100 BV range. However, they are not always superior to whole food sources.
For instance, a whey shake may provide as much protein as a lean chicken breast, but a shake does not stimulate the metabolism. Digesting and processing a chicken breast requires that the body use energy—boosting the metabolic rate by as much as 30%. This is good news for fat loss.
Learning what to eat after cardio is both a science and an art. If you stick to the guidelines of eating within an hour after your cardio session, you’re getting enough calories and fluids, and you stick to the 3:1 ratio of carbs to protein, you will make sure you are getting the most out of your post-cardio nutrition. Keep in mind that these are guidelines, and you will need to experiment and pay attention to find your own optimal numbers.