Essentials of Nutrition for Sports

Protein

Protein Key Points •^

Aim to ingest 10% to 20% of calories from protein. The upper end of the range is for aerobic endurance athletes exercising more than 10 hours per week.

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Said differently, aim for up to 1.5 grams of protein per kilogram (0.7 grams per pound).

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Watch for bad company—substances harmful for health that may accompany otherwise good protein sources.

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Get a mix of proteins. A variety of foods will ensure that you get all of the amino acids you need.

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Balance carbohydrate and protein. Keep up the carbs. Endurance athletes need carbohydrate for intensity training.

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Too much protein can potentially weaken bones.

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There is little evidence that athletes need protein supplements.

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There is little evidence that amino supplements are of value, except in a few disease states.

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Whey protein has no magical qualities.

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The role of protein in recovery drinks, if any, is overstated.

Background

Protein, a basic structure material of all cells, is also biologically

active in enzymes, immunoglobulins, hormones, neurotransmitters, nutrient transport and storage compounds, and cell membrane receptors.

Protein is needed for muscle formation. Enzymes are important

in speeding up many body processes.

Proteins are made up of amino acid units. There are 22 common

amino acids. They mix and match in thousands of different combinations to make up specific proteins.

The body cannot manufacture nine of these amino acids; it must
get these essential amino acids from diet.

Requirements: RDA

The US Food and Nutrition Boar

d (FNB) young adult daily RDA

is 56 grams per day for men and 46 grams per day for women.

Growth, pregnancy, lactation, and exercise increase needs. The FNB Acceptable Macronutrient Distribution Range is 10%

to 35%.

Generally, 10% to 15% of total daily energy intake should be

consumed as protein. Requirements by Quality

The amount of protein needed to meet the requirements for

indispensable amino acids differs

depending upon the protein source.

Protein needs are minimal when the dietary protein is of high

quality: it is highly digestible, and provides amino acids in the proportions in which they are required. Requirements by Activity

Sedentary adults probably need less than 0.5 grams of high-

quality protein per kilogram of body weight. A 60-kilogram (132 pounds) sedentary adult might do fine on just 30 grams of high-quality protein.

The RDA is higher, in part because not all protein is high-

quality, not all is easily digestible,

not all adults are sedentary, many

weigh more than 60 kilograms, and

some additional protein is added

as a safety margin to cover individual differences.

Those engaged in recreational activities may use up to 0.8 grams

per kilogram.

A few studies have shown that competitive endurance and

strength athletes may use up to 1.5 grams per kilogram.

Nutrition for Sports, Essentials of 56