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Whey Protein



What is Whey Protein?  Whey protein is a derivative of milk.  Milk consists of two types of protein: 1) Whey, and 2) Casein.  Both casein and whey protein have traditionally been used by body builders, and strength athletes alike, to increase the rate of protein synthesis (muscle building), decrease the rate of catabolism of muscle mass (muscle breakdown), and consequently to improve the rate of recovery following exercise.


Who might benefit from Whey Protein?  Any athlete looking to increase their lean muscle size, improve their rate of recovery, and improve immune health, and reduce body fat levels may benefit from whey protein.


What does research say about Whey Protein?  Of the two types of protein (whey and casein), whey protein has been demonstrated to have the greater benefit on muscle growth and recovery after exercise and helps to lower body fat levels (Lands et al., 1999).  The increased levels of muscle growth are likely to be as a result of an increased rate of protein synthesis and due to a reduction in the levels of cortisol (Markus et al., 2000).  Cortisol is a stress hormone, released during periods of physical or mental stress. It is known to have a negative effect on muscle growth by increasing the rate of catabolism (muscle breakdown).  This is of particular concern to bodybuilding/strength athletes since it will limit the effectiveness of training programmes by lowering potential gains in muscle. 

There are two main types of whey protein: 1) whey concentrate, and; 2) whey isolate. Whey concentrate is just the basic form of whey after it has been separated from casein.   Whey isolate normally goes through a special filtration process in order to increase the concentration of protein.  Typically whey concentrate may contain 70-80% protein whereas whey isolate would normally contain at least 90% protein, with a much lower level of carbohydrate and fat than whey concentrate.  Whey isolate will also have a higher level of branch-chain amino acids (BCAAs).  BCAAs have been demonstrated to be effective at helping to maintain and increase muscle mass.    

Some whey isolate will also contain partially pre-digested proteins these have been pre-digested by a process of enzymatic hydrolisation which are more readily absorbed into the blood stream and will therefore reach the muscles more quickly.

Whey protein isolate has proved particularly effective at promoting gains in muscle mass.  Subjects were observed to gain 8 pounds more lean muscle than when using whey isolate than subjects using concentrate (Cribb et al., 2002).


How should I take Whey Protein?  It is generally recommended that bodybuilders/strength training athletes should be consuming 1.5-2.0g of protein per kg of bodyweight.  Therefore if you weigh 100kg, your protein needs would be 150-250g of protein per day.  If your diet provides 100g of protein then you should be consuming an additional 50-100g of protein per day. This can easily be achieved through supplementing your diet with whey concentrate or isolate.  Protein should be consumed just before a workout (30-60mins before) and immediately afterwards (within 60mins) since protein supplementation close to training has a greater muscle building effect (Levenhagen et al., 2002).    

When not training athletes can help to keep the body in a positive growth state by consuming approximately 25g of protein (the body cannot utilise more than 25g at one time) every 2-3hours.  Many athletes like to take protein last thing at night to help to promote muscle growth overnight and to reduce muscle breakdown.  Since whey isolate and concentrate are fully absorbed and utilised within 1-2 hours of drinking they are not necessarily a good source of protein to take overnight.  Consider using a slower digesting protein overnight such as casein which will keep protein levels elevated for longer in the blood. 



Cribb, P. J., Williams, A. D., Hayes, A. and Carey, F. (2002) The effect of whey isolate and resistance training on strength, body composition, and plasma glutamine. Medicine and science in Sports and Exercise. 34, S1688. 

Lands, L. C., Grey, V. L. and Smountas, A. A. (1999) Effect of supplementation with a cysteine donor on muscular performance. Journal of Applied Physiology. 87, 1381-1385. 

Levenhagen, D. K., Carr, C., Carlson, M. G., Maron, D. J., Borel, M. J. and Flakoll, P. J. (2002) Postexercise protein intake enhances whole body and leg protein accretion in humans. Medicine and Science in Sports and Exercise. 34, 828-837. 

Markus, C. R., Olivier, B., Panhuysen, G. E. M., Gugten, J. V. D., Alles, M. S., Tuiten, A., Westenberg, H. G. M., Fekkes, D., Koppeschaar, H. F. and De Haan, E. E. H. F. (2000) The bovine protein alpha-lactalbumin increases the plasma ratio of tryptophan to the other large neutral amino acids, and in vulnerable subjects raises brain serotonin activity, reduces cortisol concentration, and improves mood under stress. American Journal of Clinical Nutrition. 71, 1536-1544.


Although, every attempt is made to ensure the accuracy of the information on this site, the publisher does not accept responsibility for the accuracy of information on this site. This material is not intended for use to diagnose, treat, cure, or prevent any disease.  The publisher does not accept any responsibility for consequences that may arise through the consumption of any supplement or nutritional product discussed on this site. You should always consult a physician, doctor, nurse, pharmacist or health practitioner before consuming any nutritional supplement.  Always read the product label and be aware of any possible side-effects or possible drug interactions before taking any nutritional product.

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Last modified: 01/05/06