UBC Triathlon
Would you like to react to this message? Create an account in a few clicks or log in to continue.

Nutrition Article: Nutritional Aspects of Recovery

Go down

Nutrition Article: Nutritional Aspects of Recovery Empty Nutrition Article: Nutritional Aspects of Recovery

Post by Vincent Mon Jun 02, 2008 8:55 pm

Nutritional Aspects of Recovery
By Cliff Harvey
The topic of ‘nutrition for recovery' could not be adequately addressed without making some mention of day to day nutrition. One's total health and performance, and of course recovery, is intricately and inseparably connected to the quality of our ‘every day' nutrition.

In fact we are constantly ‘recovering' from stressors that affect us on many levels. Physiological stress from simple day to day tasks, normal ‘wear and tear' and micro trauma from bumps and mishaps, emotional and mental anguish, stress, lack of sleep...the list goes on and on...and all of these occurrences require ‘recovery'.

They also provide a ‘stress load' and for each of us this is very different as is our ability to cope with it.

As athletes we also provide another large stressor upon the body: TRAINING!

Training is of course a positive stressor in that it elicits innumerable health benefits, and of course we all have our own performance goals that this training is leading us towards as well.

And to most efficiently reach those performance goals we must ensure that our nutritional recovery strategies are supporting us through refueling and repairing.

Nutrition Recovery Strategies for Athletes

Post-Workout Meals

The Post-Workout ‘window of opportunity' is perhaps the most important meal time in any athlete's day. After training we are primed to uptake carbohydrates, amino acids and many minor substrates.

Window of opportunity #1:
Within 1-2 hours after training

Immediately after training is the best time to take in HIGH levels of carbohydrate. Noted nutrition authority Dr John Berardi of Texas University has estimated levels of around 0.8g per kg bodyweight in the period immediately after training.

I personally recommend a slightly higher level of around 1g per kg bodyweight and in certain circumstances (very long rides) up to 2g per kg bodyweight (to a maximum of 220g).

This meal should be repeated with slightly lower levels of carbohydrate 1 hour later. At this meal I would look to 0.6 to 0.8g carbohydrate per kg of bodyweight.

Taking protein with both these meals is crucial. Fast digesting proteins like whey will not only encourage a greater level of protein synthesis (accelerating muscular recovery) but will also encourage a greater insulin release after training – thereby allowing a greater deposition of carbohydrates and other substrates such as creatine.

Other substrates and micronutrients:

Several nutrients will help encourage greater glucose disposal including the insulin potentiators Alpha Lipioc Acid and some other more esoteric substances such as 4 hydroxy-isoleucine.

Creatine, glutamine and BCAAS are also uptake extremely efficiently straight after training and if they are being taken should be included in this meal.

Because of the stripping of chromium from natural carbohydrate foods during processing I have quite recently become an advocate of the addition of chromium to post-workout meals where large amounts of carbohydrate powders are included. Additionally Chromium enhances insulin's ability to deliver nutrients into the cells by increasing insulin sensitivity. Athletes require additional amounts of this vital trace mineral. Research has shown that athletes' urinary chromium levels are increased fourfold following continuous aerobic training of 45 minutes or longer".

Creatine has been extensively studied and proven to be efficacious. Because it is transported into the muscle by insulin, it is an extremely effective time due to the amounts being released in response to the post-workout recovery drink.

Glutamine has been shown in controlled studies to increase muscle glycogen resynthesis and increase whole body carbohydrate storage. Glutamine is also a very important nutrient for maintaining proper immune function and supplementation may decrease incidence of illness and infection in hard training athletes.

Window of opportunity #2:
Within 6 hours of training

To maximally encourage total recovery of glycogen stores after hard training sessions it is important to keep feeding carbohydrates to the muscles in the hours after training.

Levels of ‘glycogen synthase' (the enzyme responsible in part for the conversion of glucose in the blood into stored glycogen in the muscle) slowly taper off after training sessions.

Insulin sensitivity also decrease and there is a lowered uptake of glucose as compared to the period straight after training. Therefore it is important to move to whole foods with a low glycaemic and insulin index rating to keep ‘drip feeding' glucose into the system.

What to have: Carb foods such as sweet potato/yams, oats, pasta, wholegrain breads, rice or the ‘ancient grains' (quinoa, spelt, amaranth, millet, barley etc) with a little lean meat, cottage cheese or beans/legumes.

Nutrition, Injury and Inflammation:

‘Recovery' itself is the defining factor for ‘stressors'. Anything requiring recovery from – is a stressor.

The grossest example of the effect of a stressor is the development of an injury.

The injury itself is the presentation of a condition or situation – so is to a certain degree a ‘symptom'. – The situation may have been acute (generally what we would regard as an accident, but may have contributing factors e.g. muscle imbalance or weakness) or may result from chronic factors (over use etc.)

The inflammatory response is the first recourse for the body in its healing process from injury.

This essential process, may be overactive or of too long a duration.

The Effect of Fatty Acids on Inflammatory Processes

Nutrition has a major part to play in systemic and local inflammation. One of the major affecters of this is fatty acid balance in the body. Omega 6 fatty acids when consumed in too great an amount have inflammatory effects and can potentiate and prolong local inflammatory effects associated with injury and from the wear and tear elicited by hard training. On the other hand Omega 3 fatty acids are generally considered to be anti-inflammatory.

Why?
Two major Omega 3 fatty acids: EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) compete with the Omega 6 fatty acid AA (arichidonic acid) for positions in the phospholipid membrane (Cleleand & James, 1997) however AA will bind to these sites in preference to DHA and/or EPA.

EPA, DHA and AA are utilized from the cell membrane to form eicosanoids including prostaglandins (PGs), leukotrienes (LTs), and Thromboxanes (TXs).

Eicosanoids of the 2- and 4-series (e.g. PGE2, TXA2, and LTB4) are derived from AA and evoke a large immunological response, whereas eicosanoids of the 3- and 5-series (e.g. PGE3, TXA3, and LTB5) are derived from EPA and DHA and have lower biological potency.

The enhanced immunological response elicited by the AA-derived eicosanoids leads to the production of pro-inflammatory cytokines, whereas the production of these cytokines is reduced by EPA (Grimble, 1998).

Where AA is consumed in excess or the ratio of AA to EPA and DHA is too high there is likely to be a corresponding ‘hyper-immune', and hyper inflammatory response. (Hence the positive effect of n-3 fats in autoimmune diseases.)

(Note: There is some corresponding increase in cortisol release to counter the pro-inflammatory effects of these cytokines.)

In the modern western diet it is estimated that we consume between a 16:1 and 50:1 omega 6 to omega 3 ratio. In a natural wild human state this would more than likely be closer to 3:1!!!

Acid/Alkaline Balance and its Effect on Recovery

The modern diet is considered to be too acidic. A chronic and underlying level of metabolic acidosis is thought to exist as a result of our dietary habits.
Because calcium is strongly basic it is one of the bodies primary means of preserving blood PH within the proper range. Metabolic acidosis causes a release of calcium from bone. As a result, osteoclastic (bone degrading) activity increases and osteoblastic (bone building) activity decreases. The net result of these changes is that bone is lost in order to neutralize the acidic environment of the body.

Muscle breakdown may occur as Glutamine is freed from muscle tissue to neutralize acidity.

Metabolic acidosis may also be involved with decreased IGF-1 and Growth Hormone activity, potentially affecting muscle, bone and connective tissue growth, repair and maintenance.

What's Acid and What's Alkaline?

Acidic foods as a rule are meats, dairy and grains. Several authorities have espoused low protein, low meat and dairy diets to offset metabolic acidosis without always recognizing the value of many nutrients found within these foods.

Highly alkaline (or alkaline forming foods) are found within the fruit, berries and vegetables groups.

If we eat more vegetables our diets will become more basic and will more closely resemble an ancestral diet that created less metabolic acidosis!

Protein – The fundamental building block.

The traditional ideology is that we only need about an extra teaspoon per day of protein over the minimum daily requirement for musculo-skeletal remodeling and repair, but there are compelling arguments supporting a higher protein intake.

(Adapted from “Protein Prejudice” by Dr John Berardi PhD)

Increased Thermic Effect of Feeding — While all macronutrients require metabolic processing for digestion, absorption, and storage or oxidation, the thermic effect of protein is roughly double that of carbohydrates and fat. Therefore, eating protein is actually thermogenic and can lead to a higher metabolic rate. This means greater fat loss when dieting and less fat gain during overfeeding. (This can be an important factor for athletes who have been forced into greater levels of inactivity due to injury)

Increased Glucagon — Protein consumption increases plasma concentrations of the hormone glucagon. Glucagon is responsible for antagonizing the effects of insulin in adipose tissue, leading to greater fat mobilization. In addition, glucagon also decreases the amounts and activities of the enzymes responsible for making and storing fat in adipose and liver cells. Again, this leads to greater fat loss during dieting and less fat gain during overfeeding.

Increased IGF-1 — Protein and amino-acid supplementation has been shown to increase the IGF-1 response to both exercise and feeding. Since IGF-1 is an anabolic hormone that's related to muscle growth, another advantage associated with consuming more protein is more muscle growth when overfeeding and/or muscle sparing when dieting.

Improved Weight-Loss Profile — Brand spankin' new research by Layman and colleagues has demonstrated that reducing the carbohydrate ratio from 3.5 - 1 to 1.4 - 1 increases body fat loss, spares muscle mass, reduces triglyceride concentrations, improves satiety, and improves blood glucose management (Layman et al 2003 — If you're at all interested in protein intake, you've gotta go read the January and February issues of the Journal of Nutrition. Layman has three interesting articles in the two journals).

Increased Protein Turnover — All tissues of the body, including muscle, go through a regular program of turnover. Since the balance between protein breakdown and protein synthesis governs muscle protein turnover, you need to increase your protein turnover rates in order to best improve your muscle quality. A high protein diet does just this. By increasing both protein synthesis and protein breakdown, a high protein diet helps you get rid of the old muscle more quickly and build up new, more functional muscle to take its place.

Increased Nitrogen Status — Earlier I indicated that a positive nitrogen status means that more protein is entering the body than is leaving the body. High protein diets cause a strong positive protein status and when this increased protein availability is coupled with an exercise program that increases the body's anabolic efficiency, the growth process may be accelerated.

Increased Provision of Auxiliary Nutrients — Although the benefits mentioned above have related specifically to protein and amino acids, it's important to recognize that we don't just eat protein and amino acids — we eat food. Therefore, high protein diets often provide auxiliary nutrients that could enhance performance and/or muscle growth. These nutrients include creatine, branched chain amino acids, conjugated linoleic acids, and/or additional nutrients that are important but remain to be discovered. This illustrates the need to get most of your protein from food, rather than supplements alone.

Cofactors (vitamins and minerals)

Analogically vitamins and minerals are the keys that unlock cellular processes.

They also provide raw materials for specific structural matrices in the body (calcium). Therefore we need to ensure we are receiving ample micro-nutrients particularly those most involved with bone and connective tissue (calcium, boron, magnesium, manganese)

Important nutrients for recovery from injury:

Glucosamine and Chondroitin
Thought to aid repair and maintenance of connective tissue but studies have been mixed. Glucosamine and Chondroitin are integral components of joint connective structures but critics have compared taking supplements as analogous to eating hair to cure baldness!

However anecdotal evidence in practice is positive both for osteoarthritis and sports related injuries. Many studies do show a positive effect on repair and pain and inflammation reduction particularly for osteoarthritis.

Animal studies have also shown definite effects on cartilaginous matrix formation as a result of Glucosamine and Chondroitin.

Vitamin D
As well as its effects on immune modulation, mood, insulin function and corresponding relevance to heart disease, cancer and mental health Vitamin D has a critical role in not only bone formation but also in reducing inflammation in the body. Several markers of inflammation (including c-reactive protein and IL-6) are reduced by adequate exposure to sunlight or dietary vitamin D. Chronic Pain may also be exacerbated by low vitamin D levels.
Vincent
Vincent

Posts : 69
Join date : 2008-02-27

Back to top Go down

Back to top


 
Permissions in this forum:
You cannot reply to topics in this forum