Thursday, December 17, 2009

Pre-Workout Protein Boosts Metabolism

We were recently on the topic of fasted training and the need for pre-workout protein intake as a slight compromise to training completely fasted.

I argued that the need for pre-workout protein intake was due to this being a case where the benefits (increased protein synthesis) simply outweighted the negatives (insulin increase; low insulin being a determinant of the fasting state). It's also known that BCAAs independently affects the same myogenic pathway through which fasted training may increase protein synthesis in response to post-workout nutrition.

On the whole, the scientific evidence that speaks in favor of pre-workout protein for increased protein synthesis and muscle growth is strong. Some researchers even speculate that it may be just as important as post-workout protein intake.

Last week I came across another study which makes a strong argument for pre-workout protein to facilitate body fat loss. Let me give you a brief summary of the findings.

Participants were recruited for two experiments where they ingested 18-19 g whey protein or carbs 20 min pre-workout. It should be noted that they all had weight-training experience; they were not newbies. Resting energy expenditure (REE) was measured on the morning before training and at the 24- and 48-hour marks post-workout. Respiratory Exchange Ratio (RER) was also measured at these time points; in short, RER is a way to quantify the ratio of fat, carb and protein oxidation at rest.

The training was in the form of a full-body session, with nine different movements trained 4 x 10-12, with a 2 min rest between sets. Bench press, squats and sit ups were some of the movements of choice.

Results showed that REE was significantly elevated at the 24-hour mark when compared to baseline.

Using a typical 80 kg/176 lbs male as an example, here's what the experiments showed

Baseline (before training): 1730 kcal

24 hours post-workout (carbs): 1790 kcal (+3.5% vs baseline)

24 hours post-workout (protein): 1880 kcal (+8.5% vs baseline)

48 hours post-workout: at this point, no clinically significant differences where seen between carbs and protein, but REE was still elevated approximately 6-6.5% above baseline in both experiments.

It's interesting to note that the carb-supplemented experiment caught up with the protein-supplemented experiment in terms of REE at the 48-hour mark, while lagging behind big time at the 24 hour mark. The difference of 90 kcal between carb and protein-supplemented experiments can be seen as fairly substantial in this context. It's more than what many thermogenic supplements would yield. The degree of latency is also interesting. One would hardly think that your pre-workout nutrient intake would affect protein synthesis 24 hours later.

REE was tilted towards increased fat burning at the 24-hour mark, but this effect was not affected by pre-workout nutrition. In this case there were no differences between protein or carbs.

Why does pre-workout protein boost metabolic rate when carbs doesn't?

The higher REE observed in the protein-supplemented experiment can be explained by increased muscle protein synthesis, which is a metabolically costly process. Older studies show that consuming pre-workout protein increase protein synthesis far more effectively than pre-workout carbs. This effect is due to shuttling amino acids to the working muscles, which in turn may increases protein synthesis for up to 48 hours. It goes without saying that if no dietary amino acids are present at this time, the effect would be blunted, which is what occurs if one would work out completely fasted or with carbs only.

The researchers put forth another hypothesis for the increased REE seen in the protein supplemented group. Pre-workout protein blunts cortisol throughout the day, which is another effect not seen fasted or with carbs only. In this context, lower cortisol could boost metabolic activity of muscle protein synthesis by allowing it to go on unscathed (cortisol increase protein breakdown and decrease synthesis).

In short, you have everything to gain by ingesting protein shortly prior to your "fasted" training session. The argument that pre-workout protein would interfere with fat burning can be laid to rest once and for all. Pre-workout protein will not only lead to better muscle and strength gains, but also help with fat loss due to it's effects on metabolic rate.

To summarize:

* Ideally, ingest 10 g branched-chain amino acids (BCAA) or 10 g essential amino acids (EAA) 5-15 mins prior to training.

* Alternatively, ingest 30 g of whey protein 5-15 mins prior to training. This will yield similar amounts of BCAA as the above protocol.

* Break the fast post-workout. Your 8 hour feeding window starts here.

* Ideally, break the fast with your largest meal and taper caloric content of meals downwards throughout the day. End the 8-hour feeding window with a lower carb meal containing slow digesting protein such as cottage cheese or eggs. Meat served with fibrous veggies is another option (meat is a fairly "fast" protein, but fiber will slow digestion).


Fredrik said...

Good post. Thanks, Martin. Keep up the great work.

Erik said...

I found the following a bit confusing:

"PURPOSE:: To determine if protein supplementation (PRO) prior to an acute bout of heavy resistance training (HRT) would influence post-exercise resting energy expenditure (REE) and the non-protein respiratory exchange ratio (RER).
CONCLUSION:: Timing PRO prior to HRT may be a simple and effective strategy to increase energy expenditure by elevating REE the day after HRT."

But what they actually did was compare carbohydrate ingestion to protein ingestion preworkout...

Has the comparison to no food intake preworkout already been done earlier? Anyone with full text access who knows?

Kevin Joel Smith said...

Would 5 or 10mg creatine work as a pre-workout protein?

Unknown said...


That's a good point. Jamurtas et al showed REE to be elevated by approx 5.5% at the 24-hour mark after fasted training.

There might be similar studies around, but this one was cited in the full text.


No. Creatine is not protein.

Unknown said...


I am hardly well versed on these topics, so forgive me if my questions come across as ignorant or foolish sounding.

I have seen some discussion of using a dose of 3-5 grams of leucine in place of BCAA's or EAA. Would this have any validity or is it just flat out more sensible to stick with around 10 g's BCAA's as you mentioned?

Along that same line, your 10g number not only sounds reasonable, but it would also be very cost-effective compared to those recommending 0.2g BCAA's per pound/0.44g BCAA's per kg. Were those who had previously recommended such a high dosage either just a bit prior to or during training way off the mark? Based upon your recommendation, I get the feeling that is the optimal amount to get the positive benefits without pissing money down the drain.

As always, thank you for sharing and for your helpful feedback.

Unknown said...

Interesting find! I didn't read the paper you linked.... was the difference in calorie expenditure between carb and protein pre-workout groups statistically significant, or was there a lot of noise within the two groups?

And, I know you're not here to endorse any specific brand of whey protein, but is there any brand you do NOT recommend? Or, is there anything we should be cautious of?


Yew-wei Tan said...

Very Informative. I'd assume though that you're still an advocate of having a small meal preWO with 40-50g protein.

On a different note, your old recommendation for eating on non-training days has always been to stack a large portion of the calories in the first meal breaking the fast. Has that changed in recent years? If so, what is your recommendation now?

I'd think this is a question that is much better answered by anecdotal reports from your numerous clients and yourself. Which is ultimately the best resource for real-world results. =)

Anonymous said...

Great stuff as always Martin...thanks

Anonymous said...

Very interesting post, I have a question though, what if I mix my weight training with cardio, is it enough with an intake of 30 gr whey protein? Or should I adjust with some carbs aswell?

Thanks for a very informative website!

Unknown said...


'Would this have any validity or is it just flat out more sensible to stick with around 10 g's BCAA's as you mentioned?'

Maybe, but it's not been investigated in a comparative study so it's hard to say for sure.

'Were those who had previously recommended such a high dosage either just a bit prior to or during training way off the mark?'

Off the mark. Broscience.

Unknown said...


It was statistically significant. There is no particular brand of whey that I dislike, but I haven't tasted that many either.


No, it hasn't.


Depends. Duration and intensity of the cardio session, total work volume for weights etc.

Anonymous said...

What about pre-workout fat intake? Recommended?

Unknown said...

I'd expect the effect of pre-workout fat on post-workout REE to be similar to that of pre-workout carbs and post-workout REE if that's what you're asking.

nondual said...

Is there any adverse effect to eating, say 30g BCAAs preworkout? It's not essential that I keep doing it, but it helps me get my macros closer to ideal and I was doing it merely because I hadn't read the 10g recommendation yet.

Unknown said...

The whole point of the 10 g recommendation is

a) 10 g provides maximal results and additional BCAA doesn't do anything in terms of stimulating protein synthesis and

b) 10 g will impact insulin minimally. Thus you get the advantage of pre-wo protein and fasted workouts. 30 g BCAA is unnecessary.

Lowie said...

Hi Martin,

Interesting post.

Can I substitute fresh milk instead of whey as a preworkout protein source?


Unknown said...


Anonymous said...

nice post. thanks.

Anonymous said...

Hi Martin, just found your site and love it. Quick question, my 2x weekly full body lifts are at 10:00am....are you suggesting 0 carbs before these and just the 30grams whey? How about a banana or something?

I feel like my intensity level will be shortchanged without some carb fuel before the workout.


Unknown said...

Try without carbs and see how you do. Some people believe carbs pre-workout is a must until they try fasted training and see that they do just as well without them.

Anonymous said...

Hey Martin,

I'm gonna start training fasted tomorrow. I've got my Purple Wraath that you recommend ready.

Can you confirm that one scoop of that stuff is enough for fasted training 5 minutes pre-workout? It has many substances in it, so that's why I'm asking, if it contains the 10g of BCAA's that I need. I think it has a combination of both, BCAA & EAA.

tiago said...

I just found out about your site and I am loving it. I am a grappler and my stronger workout is at the end of my feeding time which is at night. Should I make my biggest meal post my strongest workout or post my first workout which is in the beginning of my feeding time. Thanks for all the good information that you put out.

Unknown said...




Hard to say without knowing the details but I would suggest that the second post-workout meal be your largest meal.

Jim Sutton said...

Hi Martin,

We're not mice, but I thought you might be interested in this:

Branched-Chain Amino Acid Supplementation Promotes Survival and Supports Cardiac and Skeletal Muscle Mitochondrial Biogenesis in Middle-Aged Mice

It's at

Unknown said...

Martin, what is your recommendation for BCAA intake on non-workout days? Separate topic, have you looked at the amino acid content of hempseed powder as a nutritional supplement? Thanks for the great info.

Anonymous said...

Martin, I have TONS of casein around and no whey. Would taking casein 5-15 minutes pre-workout give me the same benefits as whey?

Unknown said...


No BCAAs on rest days. And no, I haven't.


No, casein is too slow to spike % BCAA in the blood.

Unknown said...

Basic Question...

Does powdered BCAA contain protien? I am reading lables on different sites and most don't list it. Do I need to take the Whey along with the 10g BCAA?? I'm in the US so if you could advise on a specific brand that would be great. Or maybe I just don't understand the lables. Thanks. Great site.

Nicky Hajal said...


Not sure if Martin minds others chiming in but here's how I understand it:

Protein is a set of 9 amino acids that our body is unable to produce - we must consume them.

BCAA (Branched Chain *Amino Acids*) is 3 of those 9 that are known to be particularly important for muscle development.

Therefore, Whey contains BCAA but in lesser amounts and along with other potentially less useful chemicals. It's redundant to take both and Whey is less of what you need, more of what you don't.


Barb Reeves said...

Hi Martin,

Not sure the best place to post this, so here goes. At the end, I do have a question about BCAA's.

I have just found your site within the week and have been reading with great fascination all your articles. I am so determined to finally lose fat and really tone. Apparently everything I have been doing for the past many years is not working, and your before and after results are most impressive. I am a 49 year old woman, I run and hike, now trying to increase weight training for more muscle definition, not going for any sort of competition. Under those circumstances, what do you consider the best information I could use to those goals? Do you cover this in your book--is your book out? Haven't been able to find it.

About the BCAA's, the whey protein isolate I am using says high in BCAA's, but does not say how many, just a huge list on the back, so it looks like a lot I will say. How do I sift through the list to know I am getting the essential BCAA's I need? Thanks so much for any input you can offer.

Charlie said...

Hi Martin,

I was just wondering if, you do indeed consume the protein pre-workout, do you consume more post-workout (in the form of a whey protein shake), or wait until the next meal? I've heard mixed opinions and I got really confused.

Thanks in advance,


Aakash said...

Hey Martin,

i just wanted to ask u whether consuming whey pre workout that is 5-15mins advisable.

It has 5.5 gms of BCAA in one scoop and 120 cals in compare to plain 10gms BCAA.
Will taking two of the whey scoops work or is one just enough?

Please i need help on this cause i have some stubborn belly fat to lose.

Thanks in advance


Anonymous said...

Thank you martin!
always good to reread your writing again!

Hallberg said...

Hi Martin.

What about taking one or two scoops of some pre workout supplement along with the BCAA/EAA? Like NO-Xplode, Jack3d etc.? Do you think that would have a negative or positive effect?

Brandon said...

Martin, how do you feel about creatine supplementation and when is the best time for usage, pre-workout or post-workout?

Jero said...

"* Alternatively, ingest 30 g of whey protein 5-15 mins prior to training. This will yield similar amounts of BCAA as the above protocol."

hi, Martin. just a quick question. when you say 30g of whey? do you mean 30g of protein? coz my whey is 30g=24g protein, about 120cal, its ON 100% whey if you must know.

and last, the pre workout whey 5-15mins of training would fall prior to the feeding stage? or can i wait till the start of feeding stage before i take my pre workout whey shake?

fast 10pm-2pm
(Breaking the fast)preWO Whey 2pm
Train 215pm-345pm
PWO MEAL/Meals 345pm-9:50pm

or is it okay to take preWO whey before training for 1-1.5 hrs?

Anonymous said...

hi martin love your work can you please answer aakash question as i am haven the same problem tanx again jody

Anonymous said...

Hi Martin,

I don't have access to the full "Timing protein intake increases energy expenditure 24 h after resistance training" study, but the abstract makes no mention of there being a group who skipped the pre-workout ingestion of protein or carbs and just ingested their protein post-workout instead.

Given this, I don't see how this study proves anything other than proteins being better than carbs when ingested pre-workout.


M3Fit said...

Hi Martin, I have a question, and I don't know if it's been pointed out...

Could the roughly 150 Cal increase in REE after the 24-hour post exercice in the Protein group, be because of a whey protein intake for example? And not just an increase boost of fat oxydation... Because a scoop of whey nearly gives this.

With this idea in mind, fasted training, that brings 5.5% of increase REE could come from some more fat oxydation...

Does this make any sense?

Antonio Wright said...

Consuming whey before you workout is not fasted training. Consume 10g of BCAA's prior to working.

Why is this so hard to understand?

Max said...

Hey Martin/Others... is the BCAA/Protein necessary before fasted LISS?

I enjoy 20-40 minute walks at roughly 60% max heartrate, and before leangains would just eat breakfast afterwards. I don't get particularly hungry after the walks, and would only have black coffee before (I had read about "bonk training").

Can I do one of these walks at 6:00 AM and continue to fast until 2:00 PM? Do I need whey beforehand?

Phazy said...

Hi Martin

firstly thank you for all information on this site.

I apologize if this question has been answered elsewhere - I could not find it.

Is there any "normal" food that I can consume pre fasted workout instead of either BCAA or Whey - I would like to avoid all supplement type products, frankly I don't trust them.


Bryan said...

Martin, you say 10g bcaa, if im taking purple wraath how many scoops should i intake preworkout? im kind of confused on that...

cllee said...

hey Martin i am new to this and just getting started is it possible to use eggs to replace bcaa ?

Carlos Gama said...

Would the protein before working out start the feeding clock? Or you would still be in a fast state?

Greetings from Brazil

sam said...

so are you supposed to train fasted with only BCAA in you or can you take in Whey before you train to?

jp said...

so im still a little confused just to clear it up again which you did. preworkout protein drink is ok on a fasted state but bcaa are recomended more? or should i be taking both protein drink and bcaa pre workout?

Jim said...


I normally fast from about 11pm - 5pm-ish the following day. Because of my short eating window, I'm only getting, maybe 100g of protein per day. I train fasted at 8am, 4 days/wk, and am getting leaner while adding some muscle.

My question though is, what effect would either 30g whey, or 10g BCAAs have on autophagy?


Anonymous said...

Hi Martin,
Is there a specific duration of time for which pre-workout BCAAs provide benefit? In other words, will 10 grams last for a while, or should you "re-up" at a certain point? For example, my football team's workouts usually consist of 60-90 minutes of weight training followed by 30 minutes of conditioning; will 10 grams wear off by the time conditioning rolls around? Also, during 2-a-days, will 10 grams before morning sessions be okay for the whole day or should I take an additional 10 grams before afternoon sessions? Thank you

Steve said...

Curious on what JP said

Mark said...

hey jp, when you say protein drink, are you referring to something made from your typical whey powder? if so, BCAAs are preferred since they are pure aminos, not mixed with any sugars (or other carbs). Lots of whey powders contain a lot more than just whey. Plus BCAAs are more quickly/easily assimilated than whey protein.

James said...

If i'm taking 30g of whey pre workout this contains something like 115 calories does this still not count as breaking the fast?

Also when do you suggest is the best time to take creatine?

Anon said...

BCAA or Whey preWO would mostly be wasted since the body will convert it to glucose during the workout.

Randy said...

For those of us who have long hours and typically weight train in the early morning say 5:00am. Would you simply not eat post workout until 12pm and break the fast then? Or does a morning workout simply not work with intermittent fasting.


Anonymous said...

i wake up at 5.30 and walk for around 45 mins shall i have my bcaa and glutamine mix before that? i am fasting till around 2pm but i train at around 6 til 7 pm but id love to train fasted bu is it a bad idea to wait that long? i also have creatine post workout is that ok?

Jay Horn said...

I am still wondering about the insulin spike after BCAA consumption. BCAAs are insulinogenic.

Would this compromise HSL activity that increases fat mobilization when performing high intense work right after consumption of BCAAs??

Anonymous said...

I tried to follow that research link but I couldn't acquire the population data. Do you have access to the data sets or to any REE development?

My name is Martin Berkhan and I work as a nutritional consultant, magazine writer and personal trainer.

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