Protein Pulse Feeding May Revolutionize the Way We Plan Our Meals

by Bryan Haycock MS, CSCS

When it comes to protein one thing is certain, bodybuilders eat a lot of it. You may have your preferences as to brand or even what source (i.e. egg, whey, casein, soy, meat, goldfish, etc.), but you will be hard pressed to find a bodybuilder or fitness competitor who isn�t constantly thinking about where his/her next protein meal is coming from.

I have had many discussions about optimal amounts of protein with my good friend Lyle McDonald. These discussions have led us to believe that despite all our efforts to alter the amount of protein we retain, few if any practices currently being employed by bodybuilders actually work. These discussions, along with some recent research, have led me to some conclusions that may surprise you.

A couple of recent studies really got me thinking. A researcher by the name of Marie Arnal out of France had the idea that perhaps you could increase 24-hour protein anabolism by using a diet that was both "high" and "low" in protein. You may ask, "How can a diet be both high and low in protein?" By a method called protein pulse feeding. Simply put, you consume about 80% of your daily protein at one sitting, the rest of the day you keep protein intake fairly low (for bodybuilding standards anyway).

Here is what she and her colleagues found. In "elderly women", nitrogen balance was more positive with the pulse feeding than with protein spread out (54 � 7 compared with 27 � 6 mg N/kg FFM/day).(1) Protein turnover rates were also higher with the pulse than with the spread diet (5.58 � 0.22 compared with 4.98 � 0.17 g protein/kg FFM/day), mainly because of higher protein synthesis in the pulse group (4.48 � 0.19 g protein/kg FFM/day) than in the spread group (3.75 � 0.19 g protein/kg FFM/day).

Ok, Ok, many of you are probably thinking that you have nothing in common with elderly women. Just bear with me for a moment. They did the same experiment with 26-year-old women. (2) Surprisingly they found very little effect of protein pulse feeding on nitrogen balance in these young subjects. Keep this in mind�

Finally, they found one other effect of protein pulse feeding. Protein turnover modifications induced by the protein pulse pattern for 14 days persisted at least 1 day after both young and old subjects had stopped the diet. (3) In other words, their bodies became more anabolically responsive to protein meals after utilizing a protein pulse-feeding pattern and this continued for at least a day when normal feeding was resumed.

So in summary, research has shown that in individuals who are aging, protein pulse feeding (i.e. eating most of your daily protein intake at one meal) may lead to greater gains in muscle mass over time by increasing the anabolic effect of a high protein meal, and decreasing catabolism thereafter if protein intake is reduced for the remainder of the day.

Now here is where you might be surprised, when you step back and take a look at what they found, you see that eating protein all day in many small meals, or eating a ton of protein in one big meal, made no difference in nitrogen retention in young women. This makes perfect sense with respect to how the body�s systems have evolved to ensure survival (i.e. by altering metabolism according to nutrient intake). If you eat low protein, your body conserves protein. If you eat protein all the time your body breaks it down, oxidizes it and spits it out. It could very well be that all the fuss bodybuilders make (including myself) about where and when their next protein meal is coming from might be for nothing. It could very well be that it is more anabolic to eat large amounts of protein after training (~80% of daily total) and keep protein around 10-12% of meals there after. Believe it or not, there is other research supporting this hypothesis indirectly. Up until now there has been no use in bringing it up with most bodybuilders because of the "tradition" of eating protein in a constant fashion all throughout the day. In time we will see more research on this issue and perhaps Protein Pulse Feeding will become a viable alternative to grazing on meat all day. I can already hear the nay sayers�.

2: Arnal MA, Mosoni L, Boirie Y, Houlier ML, Morin L, Verdier E, Ritz P, Antoine JM, Prugnaud J, Beaufrere B, Mirand PP. Protein feeding pattern does not affect protein retention in young women. Journal of Nutrition. 2000 Jul;130(7):1700-4.

3: Arnal MA, Mosoni L, Boirie Y, Gachon P, Genest M, Bayle G, Grizard J, Arnal M, Antoine JM, Beaufrere B, Mirand PP. Protein turnover modifications induced by the protein feeding pattern still persist after the end of the diets. American Journal of Physiology Endocrinology and Metabolism. 2000 May;278(5):E902-9.