If you complement your clean eating lifestyle with regular gym visits (as you should!) you have probably heard of nutrient timing. This refers to what you should eat and when in relation to workouts and goals. If your main goal is to get fitter and healthier and maybe lose a little bit of weight, nutrient timing won’t be as important to you. But if you want to really change your body shape by adding lean muscle and losing serious body fat you should take a close look at what you eat before and after you train.
The three main phases of nutrient timing are The Energy Phase (just before and during your workout), The Anabolic Phase (45 minutes post workout), and The Growth Phase (the rest of the day). Before we discuss what you should eat in each phase, let’s talk a little bit about fuel storage and energy systems within the body.
Glycogen (stored carbohydrate) is the primary source of fuel for our bodies during exercise. This glycogen is stored within the liver and also within the muscles themselves. During anaerobic exercise such as weight lifting and high intensity cardio intervals this glycogen gets depleted, causing you to feel weak and fatigued (Levenhagen et al., 2001). Another important hormone within the body is cortisol, which increases in the blood during exercise. When glycogen stores are insufficient to supply energy demands cortisol triggers the muscles to release amino acids that are sent to the liver to be metabolized for energy (Di Pasquale, 1992c). In other words, cortisol eats your muscles as you are trying to build them. By keeping your glycogen stores full you provide your body with adequate energy to fuel your workout and depress the damaging effects of cortisol. One of the ways we can do this is by eating a meal in the Energy Phase (pre workout).
The pre workout meal should be a combination of carbs and protein, ideally in a ratio of 4:1 grams of carbohydrates to protein. This would be approximately 6 grams of protein and 24 grams of carbohydrates (Chambers & Kravitz, 2009). If you will be working out less than an hour after eating, make sure your carbs are fast digesting, like fruit or another high glycemic carb. Stay away from high fiber/low glycemic carbs like brown rice and fibrous veggies close to workouts because they are slower to digest. Although this is normally a good thing, in this case we want the stomach to be empty! When you start training one of the adaptations of the body is to shunt blood flow to the working muscles and away from the stomach. If you have eaten recently and not had time to fully digest then this food will sit undigested while you train. Not only is this uncomfortable but you will have an unpleasant surprise when you finish training and that blood flow returns to finish where it left off. If your pre workout meal does include slow digesting carbs then eat then 1.5-2 hours before you train. A good pre-workout meal could be an apple and Greek yogurt or some chicken and sweet potato.
The Anabolic Phase is the 45 minutes immediately following your workout. It is during this time that your body is most able to uptake nutrients to replenish your energy stores and promote muscle recovery. During this phase you should consume a combination of carbohydrates and protein in a 3:1 gram ratio of carbohydrates to protein, or approximately 15 grams of protein and 45 grams of carbohydrates (Chambers & Kravitz, 2009).
The Growth Phase, more commonly known as the rest of the day, is when muscle repair and growth occurs. During this time it is important to continue feeding your body clean, healthy food in order to facilitate the rebuilding of muscle tissue. Depending on your goals you can alter your carbohydrate intake slightly. If your goal is fat loss you want to consume the majority of your daily intake of carbohydrates before and after your workout. For the rest of the day keep your carbohydrate servings very small and mostly non-starch based. Fill up on fibrous carbs like vegetables instead. If your goal is muscle gain then you will want to consume carbohydrates in combination with protein regularly throughout the rest of your day. This will maintain insulin sensitivity within the muscles and allow the body to continue to replenish glycogen stores and stay in the anabolic (building) state (Ivy & Portman, 2004).
Nutrient timing will allow you to maximize your nutrition by taking advantage of the hormonal adaptations of the body in response to exercise, both immediately and over time.
This article was researched and written by Follow @DaraCoxPT
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