Endurance Recovery
By Neal Henderson MS CSCS: Boulder Center for Sports Medicine

Intro: Recovery from training is what allows us to adapt and improve. There are many different components of recovery, but nutritional recovery is one of the more important topics. If you were to ask ten endurance athletes what they do for recovery nutrition you'll likely get ten different post-workout recovery concoctions. Should you focus on protein, vitamins, carbohydrates or simply purchase one of the many recovery products that line store shelves and appear in magazine ads? Most supplement ads tout 'maximum recovery,' but it's important to maintain awareness of some key principles with solid clinical research supporting their effects. Keep in mind that no supplement will allow you to go from a sedentary lifestyle, or one with limited training, to a 20 hour per week training schedule overnight. Gradually increasing the volume and intensity of your training will allow physical and physiological changes on the structural and cellular level, which support strong performance increases. The following recommendations can help you stay fueled during your scheduled training program and during periods of high mileage and intense training.

Recover from what?
Before getting into the importance of additional nutrients in recovery, we need to ask the question, recover from what? Since endurance athletes are involved with such varied workouts, there is no single product or magic food that can supply what is needed for all these workouts. Workouts and races come in many different lengths and intensities, and two types of workouts in particular are of utmost importance to recover from: glycogen depleting or maximum lactate. A glycogen depleting workout is one during which you have put in enough time to deplete the glycogen stores in your working muscles and are on the brink of bonking. A century ride or a two and a half hour run at moderate intensity are good examples of glycogen depleting workouts. During training sessions when you exceed your lactate threshold (AKA anaerobic threshold), you are in the realm of maximum lactate workouts. Characterized by considerable lactate buildup in the working muscles, these workouts involve repeat intervals nearing your maximum heart-rate combined with a period of rest. You can see why it's important to know what you are recovering from before you decide what to use for recovery. Most other workouts do not need special recovery strategies as long as duration and intensity are lower than the workouts just described. Be wary of general recommendations that are entirely too broad to be effective.

The following are the most important nutritional strategies to focus on for optimal recovery. Remember that these focus entirely on post-workout recovery. True nutrition recovery begins before a workout since you want to make sure your fuel and fluid stores are full prior to exercise (this helps to speed the post-workout recovery process). Keep in mind that even perfect nutritional recovery strategies will not ensure improvement if you train too hard, rest or sleep to little, or have too much stress in your life to adapt to your training.

#1: Water, water, water:
The backbone of any recovery program is always water - and more specifically hydration! Water alone can give substantial benefit in your recovery, but even greater gains can be found combining it with other nutrients. However, no other nutrient or magic pill will work without water as its backbone. All cellular reactions, including the basis of ATP production (electron transport-oxydative phosphorylation) require water and oxygen. Without water, the entire process of converting nutrients to glycogen and protein is limited. Choose water first, whether by itself, in a formulated sports drink or through foods such as fruits.

Keep in mind that the average fluid loss during exercise: 1-2 liters (33.6 to 67.2 ounces) per hour. Some individuals may lose even more than that during intense workouts/races in extreme heat and humidity!

It is recommended to drink 20-24 ounces of fluid in recovery for every pound of body weight lost during exercise.

#2: Replenish your carbs:
Following water, the second most important nutrient group to consider is not proteins, but carbohydrates. The primary fuel source for endurance athletes is glycogen…period! If you don't restore your fuel, you aren't going anywhere fast, and some carbohydrates are better than others at restoring glycogen to the working muscles. Keep in mind that a window of opportunity exists where your depleted muscles open their acceptance to this fuel, further allowing for maximum replenishment. Depending on what data you reference, this window is somewhere between 20 minutes and two hours following exercise. To keep things simple, always try to start your recovery immediately following exercise. During this time, insulin sensitivity is at is highest. Insulin, which allows sugar to flow into your bloodstream, works most efficiently immediately following exercise. In addition, high glycemic carbohydrates are broken down easily and further increase the flow of glucose into the bloodstream. This glucose can then be converted to glycogen in your working muscles, in essence 'filling your tank.' To ensure you have refilled your glycogen fuel tank to the top, always practice using a high glycemic recovery product/food immediately following exercise. Glucose (also known as dextrose), a high glycemic carbohydrate, is twice as effective at restoring muscle glycogen as fructose, a low glycemic carbohydrate. Whether a carbohydrate is a simple sugar or complex carbohydrate makes little difference on the recovery rate -- the key for post-workout nutrition recovery is the food's glycemic index.(Gonzales, Roberts, Roy) Whether a food is a liquid or solid will not make a difference either, though some claims state that liquids offer more efficient absorption. But remember, regardless of the form, the glycemic index is a direct indicator of the breakdown of the food into your bloodstreamand and is most useful as a tool to help select foods for post-workout recovery.

It is recommended to eat 1.0-1.5 grams of carbohydrate (ideally high glycemic index) per kilogram of body weight immediately after exercise to promote optimal recovery.

Here is a short list of high glycemic index foods. A more complete Glycemic Foods lists are available at www.mendosa.com/gilists.htm

#3: Protein demands:
Over the last ten years the media, the body building world, fad diets, and new research have made protein the magic nutrient for recovery. Proteins play many critical roles aiding in recovery, including the building of new tissue; as a primary constituent in cell membranes and internal cell material; comprising the enzymes which allow the body to function and breakdown fat, carbohydrates and other proteins; aiding in blood clotting; acting as a critical agent in muscle contraction; and aiding in regulation of acid-base balance. Though protein is critical in many aspects of recovery, it always works better when combined with carbohydrates. A high protein meal or nutritional product with little or no carbohydrates is relatively ineffective for any endurance athlete as a recovery product. On the other hand, protein added to high glycemic carbohydrates can actually further increase the shuttling of glycogen back into the working muscle. Protein is not a preferred fuel source for your depleted muscles, and ingesting too much protein following a workout may actually hinder the resynthesis of muscle glycogen.

Six to twenty grams of total protein is recommended in the nutrition "window of opportunity" following exercise.

#4. Electrolyte demands:
With excessive sweat, the body may also require the replenishment of electrolytes. The primary electrolytes lost in sweat are sodium, chloride, potassium and phosphorus. Electrolyte replenishment typically only becomes problematic for those athletes who consume only water during a long exercise bout in heat, or poorly designed electrolyte replacement and energy drinks. A 'during race' nutrition plan should always contain some electrolytes in order to keep homeostasis. With excessive sweat, body fluids can become hypotonic (low in electrolytes) when not replenished. The key here is to simply make sure what you drink and eat following exercise contains some or all of these electrolytes. Be careful not to drink plain water following exhaustive exercise. Water alone will actually dilute your electrolytes even further, and may cause additional nausea. Most sports drinks contain sodium. The better sports drinks will focus on all of the key electrolytes in doses large enough to help you replenish your lost stores.

Focusing on these four nutrients in the post-workout recovery window will offer you a more efficient and faster recovery from your glycogen depleting or maximum lactate training sessions or races. Here is a list of further recommendations to assist you in your post-workout nutrition plan:

1) Your recovery starts before you start working out. Make sure you are properly fueled prior to exercise and replenish lost water, carbohydrates and electrolytes during exercise. Most athletes look at their post-exercise nutrition program as primary for recovery even though what is consumed prior to and during exercise is equally as important.

2) Water is the king of all recovery nutrients. Your first line of defense is to drink plenty of fluid (not plain water), as a sports drink during exercise. Ideally the drink will have easy to digest carbohydrates and all electrolytes in advanced levels. Plenty means 20-24 Oz fluid for every 1 lb. of body weight lost during exercise (Gonzales)

3) As an endurance athlete, your next line of defense is carbohydrate replenishment. Always remember that carbohydrates are your preferred fuel source. Carbohydrates, not protein, are the nutrients which fuel your workouts and if not replenished will negatively impact your performance. The Glycogen depleting workout requires 1.5g/kg body weight of high glycemic carbohydrate immediately following workout. Maximum lactate or shorter high intensity workouts which do not deplete your glycogen don't require as much carbohydrates post exercise. Cutting your post-training carbohydrate intake down to about .5 to .75 g/kg is likely sufficient for these kinds of workouts.

4) In order to repair microfiber muscle tears and rebuild what has been damaged due to a hard workout, protein is key. Approximately 6g to 20g of a quality protein should be adequate in restoring amino acid levels in the blood and nitrogen balance. However, too much protein may hinder glycogen resynthesis, so don't grab for that Body Building supplement with 50g of Protein. Glycogen depleting workout: 4:1 ratio of high glycemic carbohydrate to protein. . Maximum lactate workouts require greater muscle recruitment and hence greater tissue damage and repair. Following these workouts protein is necessary to help rebuild muscle, though this can be supplemented with less carbohydrates (see recommendation above). A ratio closer to 3:1 or 2:1 is a good target. Isolated or Hydrolyzed Proteins are absorbed more quickly than food proteins or Protein Concentrates. To maximize your protein absorption immediately following exercise look for products using the higher quality Protein Isolates and Protein Hydrolysates.

5) Key amino acids further support complete recovery. To improve recovery a supplementation program which includes at least 5g of Glutamine and 4g of the Branched Chain Amino Acids Leucine, Iso-Leucine and Valine can make a considerable difference.

6) The primary electrolytes lost in sweat are sodium, chloride, potassium and phosphorus. Make sure your recovery program contains these key electrolytes, especially when exercising in heat or for a long duration. Proper levels of these electrolytes will keep you in water balance, which affects virtually all body functions.

7) Improvement from hard exercise happens during recovery, not during your workout. Without proper rest between hard workouts, your body will not adapt and improve. If you are lacking proper rest and sleep, hard workouts are useless and can actually send you into a downward spiral of increasingly worse performances.

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