T Nation

Protein Cycling?


I had a member of my gym come to me wanting to follow a protine cycling program where you load on protein for three weeks and then the folloeing three weeks you only eat 40 g per day. What?!

So I searched the site to see what I could find on this topic. I wanted to see if anyone sees any value in a program like this.

My education and experience in sports/fitness fields are complete opposite in thinking to this whole program.

Can anyone enlighten me? Thoughts?


Personally, I think protein cycling is great. But I don't see a reason to go 3 weeks with virtually no protein. IMHO, this is too long and you'll lose too much muscle tissue OR won't be able to build any over these weeks. I think i'll hinder progress.

I constant inkake of very high amounts of protein attenuates protein synthesis. This has been known for quiet a while. One sound way to avoid this or to somewhat "reset your body" would be to add 1-2 low protein days a week. Every week.

If you've never done this before and are consuming very high amounts of protein, I'd start with 2 low-protein days a week, then switch to only one later.

For me, Mondays are my low-protein, low-calorie days. I only have my protein pulse first thing in the morning and no more than 20g of protein with dinner.
Besides that, I only have around 1'000 calories on Mondays. Which is very little for me! (6'4, 225lbs @ 8% bdf).

I belive - though I cannot prove it - that Tuesday and Wednesday, which are high-calorie workout days, are the two most anabolic days of my week!

I cyle in a low-carb day on Thursdays (no workout).

I startet this approach 6 or 6 weeks ago and made fantastic gains. I started to use Thib's peri-wo nutrition protocol, too!


Well. I don't know the 24h fasting protocol. But first, let my say a few things about fasting.

I personally had great success cycling protein as well as carbs. As far as I know, however, there is only little scientific literature covering the topic. Some studies show that constant intake of high amounts of protein slows protein synthesis (mid 90's).
Other studies clearly show that in fat and carb metabolism, there is something like an upregulation of the endocrine system or certain crucial genes. So fat storage as well as carb metabolism/glycogen storage will be increased after a period of fasting.

For protein metabolism, relatively little is know. Some studies even show that protein metabolism/sythesis is unaltered after 3 days or so of fasting and that there is no real upregulation. There was one study in the Acto Physiologica (Oxford) a couple of moth back. But I can't remember the authors names.

Additionally, as a side note, it has been shown that the capacity of increased protein synthesis in the process of wound healing is "protected" agains protein malnutrition.
So if you look at recovery from workouts as a wound healing model, protein synthesis may be a biological priority and therefore be pretty well protected.

So I can't really prove that protein cycling works. And I can't answer whether the 24h fasting protocol will work.
I do think the logic behind protein cycling is sound, there ARE some studies that supports the extrapolation of the concept into bodybuilding. But I think it's too early to give closing answers. We need to see some more studies.

To sum it up: protein cycling, as far as I know, is still pretty unexplored. I do it personally, I believe in the concept. But I can't give advice or instruction on it with a clear conscience before having this said.


Very interesting ParagonA....thank you. Dent


I think he's following the Optimum Anabolics program. IMO, 3 weeks of low protein days is too long.


Very interesting. I really have not heard much on protein cycling but I found an article from 98 on this site that discussed it.

Now, I guess this would be more conducive to a cutting period rather bulk?

Para: What have your gains been during the six weeks? Strength? Body Fat? Etc?

Tariq: Yes that is the program he found.


I'd have them on seperate days. Like Mondays and Thursdays.

I wouldn't plan a low-protein day a day after a heavy workout. This could interfere with recovery.

I plan my low-protein days after a non-workout day.


I posted my progress several times over the last 2 month. The latest post is in Thibs formum. "Bench up 15% in 4 weeks" or so.

My gains were crazy. But it's very, very hard to attribute them. This, since I started protein pulsing, low-protein days as well as Thib's peri-workout nutrition protocol more or less on the same time.

To give you a short summary. My weight went from 211 to 225 in 8 weeks. My bodyfat decreased from 10% to 8%.

I started a new intensification phase of training 5 weeks ago. Within 6 workouts, my bench went from a cluster of 5 single @ 315 to 5 single @ 363.

Almost the samee gains in squats and deadlifts (now at 5 singles at 465 and 528, respectively).

You'll find some detailled info in the thread mentioned above.

(As usual: sorry fpr the bad English...)



How much calories do you consume on your other days, and in terms of macros is that mainly from P+F meals with the exception of carbs para-workout?




I don't really count calories anymore. Did that almost 2 decades...

On my workout days, I have a protein pulse first thing in the morning. Followed by eggs (8-10 whites, 2 yolks) and 300-400g fruit.

Another protein pulse mid morning.

I workout at noon, so I start my peri-workout protocol 11am or so.

60 minues after workout another pulse, followed by a big meal 30 minutes later (500g potatoes or 125g whole wheat pasta, 250-300g chicken/fish, green veggies, Flameout)

I have the same meal - but with red meat - like 3 hours later (supper). With another protein pulse 30 min earlier.

Befor bed I have 300g of probiotic yoghurt, 1 Metabolic Drive Bar and 2 servings Metabolic Drive.

I guess I eat someting like 4'500 calories including workout nutrition on workout days. With 200+ grams of carbs not counting the protocol.
I have all my carbs (besides the protocol) after my workout. In the morning I only have fruits to replace liver glycogen.
I do believe - but cannot prove it - that the anabolic response to the protocol is bigger if I don't have a ton of carbs in the morning.


Thanks for the detailed response. I am surprised by your additional carb intake given you're following CT's advice very closely. It was my understanding that, breakfast fruit carbs aside, all carbs are ingested para-workout only?
Regardless, your progress is very impressive so why change it. I follow a similar protocol myself. I am pulsing once per day upon waking with 12g WH and 3g leucine. I also have 5-10g BCAAs 3 hours after breakfast and 2 hours before another soid meal.
My weight has stalled at 175lbs but my strength is steadily gaining. I am also quite paranoid about losing my abs (after a long battle to get them in the first place) so I'm prepared to make slow but steady lean mass gains.
The only aspect I have not incorporated consistently so far is a low protein day. I think this is the next step for me and based on your own results I will commit to it for a period to see how it goes.


CT only recommends this for those who don't tolerate carbs well and are seeking maximum fat loss.

As often happens, his response on this was taken out of context.


Anyone else using protein cycling?

I am gonna check CT's thread.


I've started having a low protein day (60-80g). Suprisingly, I don't get hungry on that day - The next day I wake up and very feel fresh and rejuvenated.


Although, I don't count calories on the weekend, I use those days as low protein days on the AD. I just focus on carbs and fat and dont really eat any meat. This is a big drop from the 350 grms i get monday - friday.