And yet another mailbag.
How Long to Take the EC Stack
Question: Hello! I have purchased your RFL handbook about 6 months ago. And have also been taking the ECA stack for about 5 months now. I really just want to know how long is safe to run an ECA stack!?? I have only taken two doses a day instead of the suggested three. this is what it looks like : 25mg Ephedrine HCI , 200mg Caffeine, 162mg Aspirin once in the morning and another in the afternoon.
Answer: Since I appear to be officially out of ideas for things to write about (cut me some slack, I’ve got 500 posts on the site), I’m doing another Q&A this week. For those unfamiliar with the acronyms, RFL is my own Rapid Fat Loss Handbook and ECA is a combination of Ephedrine Caffeine and Aspirin.
I don’t recall offhand when it really came into use but it was at least in the 90’s when it was found that the combination of ephedrine and caffeine were thermogenics (meaning that they increase energy expenditure), suppressed appetite, mobilized fat and had many other potential benefits for fat loss on a diet (other thermogenics such as green tea, capsaicin and nicotine were also studied).
Aspirin was sometimes added as well (for once I’ll spare you the mechanisms involved here) but, outside of the obese, didn’t really have any benefit. It was also never clear if low-dose aspirin (81 mg) would have the same benefit as the full 300 mg used in the studies and honestly, if someone is going to use EC (often just called the stack), I don’t recommend the aspirin.
In any case, back to the question, how long should EC be used? And the answer sort of depends on your perspective.
One thing worth mentioning is this: EC is unusual (and possibly unique) among fat loss compounds in that chronic use actually makes it work more effectively. I do mean that this is unusual in that most drugs lose, or at least appear to lose, their effect over time (it’s a little more complicated than this but I’ll save my explanation of this statement for next week or something). Ephedrine becomes more effective over time (and the idea that it must be cycled to avoid a loss of effect is not only wrong but exactly backwards). The thing is, nobody is quite sure how this might happen.
Early ideas revolved around Brown Adipose Tissue (BAT) and the idea that ephedrine might increase it. But humans don’t actually have much BAT (we have beige/brite fat and I discussed this, along with how to impact and increase it in my Stubborn Fat Solution 1.1 Patch). But the only study I’m aware of in humans shows that, if anything, EC decreases the amounts of BAT.
So, honestly, I have no idea why EC becomes more effective with regular use. But it does and that would tend to suggest chronic use is better. But that still doesn’t answer how long. In addition, the side effects of the EC stack, which include things like increased heart rate, blood pressure and general stimulation decrease with regular use. EC gets more effective and safer over time. In that sense, it could conceivably be used forever.
On the one hand, EC is really a dieting/fat loss supplement. It’s effects are small but do add up and it has been shown to have the benefits I listed above during a diet as well as others. By increasing the use of fat, it can spare the loss of skeletal muscle/LBM, for example. As well, although it’s overall metabolic effects are moderate (increasing energy expenditure by 5-10%), this helps to offset the normal diet related decreases in energy expenditure. And in that sense, only using it until the diet period ends is sort of a logical conclusion. It’s a diet compound, use it while dieting. It’s fairly logical although we might quibble over how long a diet should actually be before taking a break.
But there’s also another way of looking at this issue. At the end of a diet, a host of adaptations have occurred in an attempt to facilitate fat regain. Appetite and hunger are both up (and people show more attention to high-calorie, high-sugar, high-fat foods) and various components of energy expenditure are decreased along with the body being utterly primed to store fat at an accelerated rate. There are a huge number of factors that go into this.
Leptin is down, ghrelin is up, the other hunger hormones such as CCK, PYY, etc. are decreased and this all adds up to an integrated signal to the hypothalamus that decreases thyroid output (this is along with a decrease in conversion of inactive to active thyroid in the liver) and decreased nervous system output. And it’s that last one that is relevant here.
Getting off-topic slightly, early ideas suggested that obese individuals became obese due to low sympathetic activity. This was called the MONA LISA hypothesis which stood for Most Obesities kNown Are Low In Sympathetic Activity. Ha ha.
But other work clearly shows that there is elevated sympathetic activity in the obese. What may be happening is that low sympathetic activity predisposes people towards obesity and then this normalizes and then overcompensates when a person becomes obese. Regardless.
My point being that at the end of a diet, this same type of low sympathetic nervous system activity is present. And ephedrine and caffeine helps to offset this even after the diet is over. That is to say that continuing to use EC past the actual duration of the diet may help weight long-term weight maintenance as it helps to offset the normal diet/fat loss generated reduction in energy expenditure (at least through this one mechanism) that occurs. This assumes that it is well tolerated and effectively this is saying that EC would be a permanent part of someone’s daily intake.
And I imagine this might concern some readers (and I’m not exactly suggesting this, just commenting that it is possible). Clearly long-term weight maintenance is the big issue when it comes to fat loss; everybody can lose some amount of fat. It’s keeping it off that is the issue (though the often cited value of 90-95% failure is completely incorrect, just for the record).
The post-obese body is in a state of lowered energy expenditure and increased potential fat storage; combined with the modern environment where endless food cues promote eating, this is a real problem. And there is increasing interest in the idea that obesity should be treated as a chronic relapsing disease. And if long-term medication is required to prevent relapse….
Continuous use of the EC stack at least ameliorates some of the decrease in energy expenditure. Other compounds have also been tested here including green tea (and caffeine) and capsaican (and caffeine, because caffeine makes everything better) and it would certainly be possible to switch out EC for potentially less, what’s a good word here, let’s say controversial compounds. Doses for green tea or capsaican can be found here.
As well, there are other approaches, such as increasing activity levels that can effectively accomplish the same thing. We’ve known for a while that exercise has its largest effect on weight maintenance (rather than increasing total weight loss per se) although it takes quite a bit. And a big part of this is that by increasing exercise related energy expenditure, the other aspects of metabolic rate decrease can be offset. This allows more food to be eaten (critical for long-term hunger control) without fat being gained.
Which is all a very long way of saying what I could have written in three sentences which is
- Ephedrine works better with long-term use and there is no need to cycle it at a fundamental level
- In one sense, ephedrine is a dieting aid and should be used during the active dieting phase
- Except that continuing to use ephedrine after the diet is over might help to offset some of the adaptations that occur in response to fat loss that tend to promote fat regain. This can be accomplished through other methods such as increased activity.
Which probably doesn’t really answer the original question that directly but maybe answers something?
Cold Exposure and Calorie Burning
Question: Hello Lyle, I have came across a suggestion that if you spend most time of your day in a cold room, your body expends more energy as heat because it tries to keep a stable body temperature. It makes a sense to me. I would like to ask you whether is that true and if its, how big is the difference? It could be very small or maybe 100-200 kcals a day. Thanks you for your help.
Answer: The short answer is yes-ish but there are a few caveats; as usual I’ll trudge (hopefully briefly) through some of the physiology. The basic idea is that, by being exposed to cold, the body has to burn calories to generate heat. And there is truth to that. Some of this is due to shivering but there is also the whole brown/beige/brite adipose tissue thing that may be at play here.
Many readers may remember a lot of interest in brown adipose tissue (BAT) a bunch of years ago. BAT was found in animals originally and exists, roughly, to burn energy to make heat. In contrast to normal white adipose tissue which is predominantly stored triglyceride with very few mitochondria (the powerhouse of the cell), BAT had a lot of mitochondria but not a lot of stored fat. It existed to burn fat, generating heat.
BAT and Beta-3 Agonists
There was a huge amount of interest, drugs called beta-3 agonists (which worked amazingly in rats and mice) were developed and almost immediately crapped out. They had minimal effect in humans and any effect was short-lived. So they were abandoned by pharmaceutical companies. Remember this when you see some supplement company is pushing a beta-3 agonist; if a multi-billion dollar pharm company can’t figure this out, neither can the supplement pushers. Obesity treatment is worth billions and pharm companies stop researching dead end drugs.
And it looked like the reason had to do with the fact that adult humans didn’t have much BAT. Babies (who thermoregulate poorly) had it, a certain type of tumor (a pheochromacytoma) had it and folks exposed to chronic cold (Oh I’m a lumberjack and I’m ok) had more of it. But most adult humans didn’t and researchers sort of gave up on it.
Then a few years ago, there was a huge amount of renewed interest in BAT. Researchers looking at something else with a PET scanner and saw something they couldn’t explain. And when they looked further, it looked like BAT. Why hadn’t they seen it before? Because they were measuring under thermoneutral conditions originally. In the newer research they were measuring during cold exposure. And that’s a big part of what turns on BAT: cold exposure. there are others, a variety of compounds including ephedrine/caffeine, capsaican and others may activate BAT.
But as they dug deeper, something else came to light which is that this type of fat in humans may not be the same as the BAT found in animals (explaining why the attempts to activate it didn’t work). Rather, it’s been identified as a similar but distinct type of fat that is variously called beige or brite fat
Beige and Brite Fat
Beige/brite fat is similar in function to BAT but it’s not quite the same. There is currently huge interest in the “browning” of white fat, turning normal white fat cells into this type of thermogenic fat with the hopes that it can help stave off of obesity (and I wrote about this in some detail in my little Stubborn Fat Solution Patch 1.1 along with some pharmaceutical approaches to at least increasing the amount of beige/brite fat).
It’s still questionable how much of an impact this will actually have, though. One recent study compared either ephedrine/caffeine or a day’s worth of cold exposure; ephedrine increased daily energy expenditure by 140 calories/day with ephedrine and 80 calories/day with cold. The cold didn’t cause shivering and it was thought that the effect was through beige/brite fat activation (the titles uses brown fat but all research groups don’t seem to be aware of the distinction between true BAT and beige/brite fat).
There is also the issue that not everyone has the same amount or activity of beige/brite fat. Women seem to have more than men (which is odd given their difficulty with fat loss and fat gain) and the obese have less total or less active amounts than the lean (which is not surprising).
Trained endurance athletes actually have low activity of this type of fat and this also seems contradictory since trained endurance athletes are generally lean. But, as above, it’s unclear what real world effect this has since the caloric expenditure is very small and without drugs, it’s unlikely we’ll get full activation any time soon.
Cold and Thermal Neutral Zone
But the bigger issue with all of this is that most in the modern world live in what is called the thermal neutral zone (TNZ). This has been suggested as one of many non-food/activity related contributors to obesity. This zone is defined as the range where human metabolism is not impacted and ranges from 25-30°C (77-86° real American F units).
Outside of that, both higher and lower there is a shift in energy metabolism. But there can also be a change in appetite. This is thought to contribute to obesity in that, with heat, air condition and clothing, the modern human can make sure that they avoid what most perceive as uncomfortable temperatures; we live within the TNZ most of the time.
Heat, increasing the core temperature, can increase energy expenditure (every degree increase in core temperature increases metabolic rate by ~10%) and tends to blunt appetite for various reasons. Cold can do the same, increasing energy expenditure but often stimulates hunger.
Since the question was about cold, the numbers found in studies are anywhere from a 25 calorie per day difference up to about 185 calories/day less burned in the thermal neutral zone compared to a colder environment. The reason this is probably different than the cold exposure study above is due to shivering, the 50 cal/day study didn’t induce shivering but these studies probably did.
So how cold was cold? The experiments typically compared 16°C (60°F) to 24°C (75°F). So pretty cold. If anything between those two has been tested, I don’t know about it (researchers often use extremes to make sure they get a measurable response). Would 21°C (70°F) have a smaller effect? I don’t know.
At the end of the day, I’m not sure it matters. Unless they really like the cold, I’m not convinced that most people would be willing to be that cold all day to burn an extra 150 calories/day. It can certainly be acclimated to, usually the suggestion is to bring the thermostat down by a degree every few weeks, sleep with progressively less clothing and blankets, etc. Or you could do 15-20 minutes of moderate intensity cardio and not be cold, miserable and have to overdrive your AC (unless you do this in the winter).
There is also the question of increased hunger; if food intake goes up in response to the cold, that could easily overwhelm this small effect (exercise, in general tends to decrease hunger). Sure, if you can maintain food intake without change and if you can handle being that cold all the time, you might get some extra caloric expenditure and that might be useful. But I doubt that, in practice, most will be able to do it.
And before anyone asks about it in the comments: no I do not think that these silly-assed cold vests that are being claimed to “activate brown fat” will do much. Recall that the study above only found a 50 cal/day increase with cold exposure based beige/brite fat activation. Wearing one of these things for a short period won’t do squat.
So the answer is yes-ish. There is an effect that could add up over time (i.e. 150 cal/day extra done every day is 4,500 calories/month) I’m not convinced that practically most can do anything with it due to the hassle and uncomfortableness of what’s required.
Combining Tension and Metabolic Work
Question: Lyle, I’ve been reading up on your articles covering the pathways of muscle growth while dieting to gain mass, as well as, when dieting to lose fat. With that being said I have some questions on what to do during dieting for fat loss. In some of your articles you’ve said that the tension pathway is the best for gaining or maintaining strength with a rep range between 30-60 reps per muscle group.
Also in another article over training while dieting to lose you talked about using the metabolic pathway in order to deplete glycogen and increase metabolic rate, but that it is not the best for maintaining mass. You also talked about combining the two pathways on different days of the week or different body parts on the same day (1 muscle tension/other muscle metabolic).
SO my question is can you do heavy tension training and metabolic training of the same muscle group on the same day? Also is the rep range for the metabolic pathway the same 30-60 rep range per muscle group? Or is there an increas e rep range? Sorry if I’m asking a question that you have already answered, if so then please direct me to the article. Thanks
Answer: Ok, the above is a little bit all over the place so let me see if I can de-all over the place it. The question is sort of jumping from mass gains and dieting which aren’t the same. Let me get dieting out of the way. In a previous article I looked at metabolic and tension training, roughly heavy work in the 6-12 repetition range vs. high reps in terms of what should be done on a diet. Basically I was addressing a very old (and mainly steroid-driven) idea that switching exclusively to high reps and short rests on a diet is not optimal for a natural lifter.
Take away the tension stimulus and muscles go bye-bye unless you have steroids to protect against it. The only exception being beginners for whom most gains are neural, there is no increased muscle mass to lose and glycogen depletion may be beneficial to enhance whole-body fat burning during dieting. Which isn’t to say that depletion work doesn’t have it’s place in addition to tension work on a diet. But the goal is less fatigue and more
- Glycogen Depletion
- A Hormonal Response to Mobilize Fat (increased SNS output)
- Probably Something Else I Mentioned in the Articles but Forget
But this is also generally combined with a reduction in total tension training. Volume and frequency can be reduced fairly significantly without losing muscle. But only so long as intensity (defined here as weight on the bar) doesn’t go down.
Depletion work can be done in a variety of ways. In my Ultimate Diet 2.0, it’s done at the start of the week as either two full-body workouts to set up maximal fat loss before rebounding into an anabolic state with tension and power training. But that is a very specific setup and there are many other ways to do it.
One would be to cut heavy, tension type weight training on a diet to two-full body workouts and do two full-body depletion workouts on the other days. Another would be to follow any specific weight work with the appropriate depletion work. So do lower body depletion after lower, or chest/delts/tri depletion after that workout. See the chart
|Legs/Abs + Legs/Abs D||Back/Bis +Back/Bis D|
Or whatever, the specific split doesn’t matter, the above are just examples. Cardio after the depletion work burns off the mobilized fatty acids and it’s semi-like my Stubborn Fat Solution protocols.
But again that’s really a dieting application. What about for mass gains, can metabolic (which I would here call fatigue work) and tension training be combined? And the answer is yes.
We know that growth of muscle depends on a lot of things, a tension stimulus (provided by heavy weight) and a fatigue stimulus (provided by higher reps/shorter rest). An eccentric contraction may be required although DOMS per se probably means nothing. Early on it looked like metabolic accumulation was involved and it may still be. The hormonal response to training probably isn’t very important at all.
And while I cannot claim to have delved into the molecular pathways (involving things like mTOR, AKT and a bunch of other stuff) different types of training may activate them differentially and, while unstudied they may overlap and/or synergize with one another. Certainly over the decades a variety of approaches using heavy work (sets of 5-8) and lighter work (sets of 10-12 or 12-15) have been used for growth. And this appears in my own Generic Bulking Routine (GBR)
And I do still keep the total volume per muscle group to 40-60 repetitions although getting both types of training into the same workout usually means being at the high end of this. So a bodypart workout might be something like
Heavy Compound (bench, row, squat, etc): 4 sets of 6-8/3′ rest
Which means 4 sets of 6-8 repetitions on a 3′ rest. The goal here is to use the heaviest weights which means long rest intervals.
Isolation exercise: 2-3 sets of 12-15/60-90″ rest
This is a fatigue stimulus.
So you might do
Squat: 4X6-8 (or even 5X5) with a 3′ rest followed by leg extensions and leg curls for 2-3X12-15 with 60-90″ rest. Perhaps a better leg workout would be
Squat: 4X6-8/3′ rest
Leg extension: 3X12-15/60-90″ rest
Leg curl: 312-15/60-90″ rest
Here I recommend doing the heavy work first since quads are involved in the RDL to keep the knees straight.
Any other bodypart workout would be the same: bench/chest-flye, row/shrugback, pulldown/pullover, etc, etc.
Now, the above is great but once people get a lot stronger, perhaps into year 3 as an intermediate trainee (about year 4 of training if they do it right), two heavy workouts in the above fashion can be too much.
At this point, I think it’s better to split up the tension and fatigue work but to keep both in the same week. It’s just a basic heavy/light since medium work doesn’t fit anywhere. This looks very much like the PHaT system. So a week might look like this.
|Lower H||Upper H||Off||Lower L||Upper L||Off||Off|
Where H means heavy compounds for 40-60 total reps per muscle group.
Squat: 4X6-8/3′ rest
RDL: 4X6-8/3′ rest
Leg Press: 4X6-8/3′ restLeg Curl: 4X6-8/3′ rest
And L is more isolation work for 40-60 total reps
Leg press or leg extension: 4X12-15/60-90″ rest
Leg curl: 4X12-15/6-90″ rest
Hope that answers the question.
Size of Calorie Deficit and Muscle Loss
Question: Hello Lyle, as you know in Bodybuilding there are two phases to build muscle (off-season) and to strip off excess fat. When you want to get rid of excess fat there are different ways to plan the deficit. You can use a low, medium or high deficit. The question to me is, what is the best way to keep muscle during that period (steroid free). You need to have a deficit and therefore you also will lose muscle.
Let’s say, you are at the end of your bulking phase with 20% body fat and start dieting from there until you get to your 10% mark. Is there a difference in terms of muscle loss (catabolism) when you do it slowly with up to 500 kcal deficit or more aggressively with a deficit of 1000 kcal?? Both scenarios end when you hit the 10% mark! Do you have research on that?
Answer: Ok, first let me start with a big assumption in the above which is that you must lose muscle on a diet. This has been taken as fact for years and I’ll be honest that I used to repeat it many years ago. But it’s not really true. A lot of early dieting practices, much of which came out of the drug fuelled 80’s (and which didn’t work for naturals) do allow muscle loss. But it doesn’t have to happen if you do things correctly.
Correct here means at least three things
For example, people using my Ultimate Diet 2.0 (which alternates a very large caloric deficit for about 4 days with 3 days high calories) has gotten people very lean while gaining muscle. My Rapid Fat Loss Handbook creates a very large deficit but since protein intake is high (up to 2 g/lb for leaner individuals) and mandates proper heavy weight training, muscle loss is minimal in most people.
The problem early on was that dieters tried to do what drug users were doing. They dropped heavy weight training for high-rep/short-rest training; that causes muscle loss. They tried to maintain the same lower protein (and naturals need much more protein to spare LBM). In his review Eric Helms recommends up to 2.3-3.1 g/kg (1.1-1.4 g/lb) which is exactly what I recommended in the Protein Book in 2007.
With that said, let me answer the rest of the question. Yes, early research did suggest that there was a relationship between the size of deficit and muscle catabolism but there are some problems I see with that conclusion.
Many of those studies gave like 320-400 calories/day and maybe half of that was protein. That means that the dieters got like 50 grams of protein per day which is way below what even the obese need (1.5 g/kg protein or about 0.7 g/lb). That’s what caused the muscle loss; too little protein. And of course no resistance training. Insufficient protein causes muscle loss.
Beyond that, there have been some recent studies looking at this. The first put obese men on either a very low calorie diet for 3 weeks or a low calorie (both of which contained a stupid 50 g/day of protein which is still too low given that the dieters were about 107 kg; they needed 150 g/day or so) diet for 6 weeks to generate the same total fat loss. The low calorie diet (with more calories) actually lost MORE lean body mass probably related to the length of the diet (and the stupid low protein) but they also lost more fat.
Another study, this time in elite athletes, aimed for either slow or fast weight loss (once again, the fast weight loss athletes were done in half the time) with the slow group getting 1900 calories (a 450 cal/day deficit) and 1.6 g/kg of protein (closer but still too low) or 1700 calories (an 800 cal/day deficit) and 1.6 g/kg of protein.
The fast weight loss group lost a tiny amount of LBM (about 1 lb) while the slow weight loss group actually gained a bit of muscle. But this is kind of misleading, the athletes were training their upper bodies for the first time and the muscle gain was a newbie effect. The fast weight loss group also lost a bit more fat.
But I’d make a big point, a faster diet, in addition to probably not causing more LBM if you do it right, is over faster. If your diet is done in 3 weeks versus 6 weeks, you can get back to real training on maintenance or slightly higher calories sooner. So if you’re diet is over in 3 weeks (compared to 6) you can spend the next 3 weeks training more efficiently. I bet those 3 weeks of real training put any small amount of muscle lost back on and let you gain more muscle too.
Now, I’m not recommending that all dieters follow fast fat loss diets. But it’s pretty clear that given sufficient protein and training, any LBM loss is minimal overall. And it’s not much greater with fast fat loss. So most of these old ideas floating around are actually wrong. You don’t have to lose muscle and if you get sufficient protein, heavy training and don’t go nuts on cardio, you won’t lose more with a faster fat loss than with a slower fat loss. And you can get back to non-dieting training sooner.
How Much Protein While Dieting?
Question: You refer to “adequate protein intake” as important, but what do you consider adequate? In my case — calorie restriction of ~750-1000 kcals below BMR coupled with regular strength training? Is there a percentage of intake you consider ideal, and is it higher while dieting versus maintenance (to prevent muscle loss during times of restriction)?
Answer: The above question actually came through in the comments section of Exercise and Weight/Fat Loss: Part 2 and I thought it was important enough to address explicitly since it’s a place where I still see many mainstream diets and dieters making mistakes. It’s worth noting that bodybuilders and other strength athletes have been promoting higher protein intakes while dieting for decades and this is yet another place where modern science has ended up validating those beliefs many years after the fact.
The question of adequate protein under different conditions is one that has a long history of debate, the issue of maintenance requirements as well as protein intakes for athletes is still highly debated with science on both sides of the story (for details you can refer to The Protein Book).
With regards dieting specifically, this was a topic of much study in the 60’s and 70’s as researchers started looking past the simple issue of weight loss and into that of changes in body composition; the goal moved from weight loss per se to that of generating fat loss while minimizing lean body mass and muscle mass loss.
After much toing and froing and research had been done it was eventually found that a protein intake of about 1.5 g/kg of lean body mass (LBM; note that researchers actually used Ideal Body Weight but this is a rough proxy for LBM) was necessary to spare LBM losses in a non-training obese individual consuming low calories.
This is about double the DRI for protein (at 0.8 g/kg) at maintenance calories. So for an overweight individual at say 200 pounds and 30% body fat (this would give them an LBM of 140 lbs or 63 kg), that would be a protein intake of 95 grams of protein per day. Please note that this value is simply a minimum and dieters may still find that higher protein intakes are beneficial from a hunger blunting effect or what have you (see below).
I’d mention that at least one of the studies I referred to that found no benefit of resistance training gave something like 40 grams of protein to the subjects far less than necessary or adequate. So it’s no surprise that no protein sparing effect of exercise was seen; the diet was inadequate in the first place.
It’s worth noting that more recent research supports further benefits of increased protein intakes while dieting, beyond simple lean body mass maintenance. Protein is the most filling nutrient (meaning that higher protein intakes tend to control hunger better).
Studies have found that higher protein intakes can help to stabilize blood sugar levels while dieting which has benefits from both an energy level and appetite standpoint. Protein high in the amino acid leucine (with the dairy proteins whey and casein being the two proteins highest in leucine) seem to have extra benefit in this regard.
Now, as individuals get leaner, protein requirement tend to go up further for reasons discussed in other articles on this site. As well, regular training tends to further increase protein requirements. So lean athletes trying to lose fat while sparing lean body mass loss need even higher protein intakes than this. And we’ve known for decades now that caloric intake per se tends to impact on protein requirements; as caloric intake goes down, protein requirements go up. And vice versa.
While less data on this group is available, bodybuilders and athletes have long used a protein intake of 2.2 g/kg (1 g/lb) lean body mass as a generalized intake level and as folks get very lean, intakes of 3.3 g/kg (1.5 g/lb) of lean body mass may be required to stave off muscle loss while dieting. In some very extreme cases, such as the near protein only diet approach of my own Rapid Fat Loss Handbook even higher protein intakes may be required for very lean individuals.
So basically we have an intake continuum ranging from about 1.5 g/kg (0.68 g/lb) as a minimum for the obese non-training individual up to a high of around 3.3 g/kg (1.5 g/lb) of protein per pound of lean body mass for very lean heavily training athletes or bodybuilders with middle ground values being found in between those two extremes. You’ll note that I didn’t put any of those values in terms of percentages.
So that’s what I mean by “adequate protein on a diet” when I use that phrase. It’s context dependent with the primary variables being body fat percentage (as this goes up, protein requirements go down), caloric intake (as caloric intake goes down, protein requirements go up and vice versa), and activity (with regular activity generally increasing protein requirements).