What Is It?
Post exercise Carbohydrate – Protein supplements contain "fast" protein and carbohydrates meaning quickly digested and absorbed proteins (such as whey protein) and simple sugars (including glucose and/or glucose polymers). Often these products also contain additional amino acids and/or creatine.
What Does It Do?
While strength and endurance training and competition promote a host of physiological benefits, both types of exercise stress the body to a large degree. Not only are muscle substrates (stored carbohydrate/glycogen, stored amino acids, and stored phosphagens like ATP and phosphocreatine) depleted but also protein status becomes negative, muscles suffer structural damage, blood cortisol rises, and immune function is compromised.
Fortunately, the body is designed to respond to these changes by providing a short post exercise period in which all these negative effects can be remedied as long as proper nutrition is provided, and fast.
Well designed post-exercise Carbohydrate – Protein supplements are designed to deal with each of the aforementioned changes, rapidly replenishing muscle glycogen and muscle phospagens, rapidly shifting the body from a catabolic state to an anabolic one, managing blood cortisol, supporting immune function, and protecting muscles from excessive structural damage.
Where Does It Come From?
Post exercise Carbohydrate – Protein supplements represent the true definition of "nutritional supplement" in that they are fast digesting proteins and carbohydrates provided in a fast acting liquid form. The major protein component of a good post exercise supplement is usually a high quality, enzymatically hydrolyzed whey protein.
Whey protein makes up about 20% of the protein found in milk (80% of milk protein is casein) and when enzymatically hydrolyzed, whey protein is more quickly digested, is non-allergenic, and retains its health promoting properties. The carbohydrates in a good post exercise should come from a blend of glucose and maltodextrin (glucose polymer).
Glucose and maltodextrin are simple sugars and while simple sugars are not recommended any other time of the day, they are critical during the immediate post-exercise period for replenishing fluid and muscle glycogen.
How Do I Use It?
Strength athletes/weight lifters interested in increasing muscle mass – Sip 0.8g/kg carbohydrate and 0.4g/kg protein dissolved in 1L of water during exercise. Immediately after exercise ingest another identical beverage. Eat a solid food meal 1h later.
Strength athletes/weight lifters interested in preserving muscle mass while dieting – Sip 0.4g/kg carbohydrate and 0.2g/kg protein dissolved in 0.5L of water during exercise. Eat a solid food meal 1h after exercise.
Endurance athletes interested in optimal recovery from training/practice – Drink 0.4g/kg carbohydrate and 0.2g/kg protein dissolved in 0.5L of water 15 min prior to exercise. Immediately after exercise ingest 0.8g/kg carbohydrate and 0.4g/kg protein dissolved in 1L of water. Eat a solid food meal 1h later.
Endurance athletes interested in optimal recovery between competitions – Drink 0.8g/kg carbohydrate and 0.4g/kg protein dissolved in 1L of water immediately after exercise. Drink another identical beverage 1h later. Eat a solid food meal 1h later.
4/4 - This supplement/regimen has significant scientific backing and can produce significant benefits in most individuals.
3/4 - There exists a sound theoretical basis for its ergogenic effects; may work in certain individuals; further research is needed to elucidate their respective effects.
2/4 - Science is equivocal, animal data and human data may be conflicting; or mechanism of action may be unclear.
1/4 - Little or no science as well as poor theoretical foundation.
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About The Author
John M Berardi is one of the world's foremost experts in the field of human performance and nutrition. His company, Science Link, provides unique and highly effective training, nutrition, and supplementation programs for high level athletes as well as recreational exercisers. John is a prolific author and a sought after speaker and consultant. Visit www.johnberardi.com for more information about John and his team. Also, check out his new DVD entitled No Nonsense Nutrition.
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