The no BS MFP EDUCATION thread

Awkward30

TDEE Questions

I recently started eating closer to my TDEE, how soon should I start to see results (substained weight loss) to know it's working?

Weight loss isn't linear, but if you are eating under your TDEE you should start seeing results in about a week or two. Sometimes faster.

If I'm calculating my TDEE to my actual activity level, then I should NOT eat back my exercise calories, right?

Correct

When I finally get a HRM, can I wear it all day for a week to get a more accurate TDEE?

Thank you!

An HRM isn't an accurate way to gauge your TDEE because all it measures is heart rate. Say you watched a scary movie or got excited about something that made your heart rate go up? Faster heart rate, but that didn't mean you actually equaled a calorie burn from exercise with the same heart rate.

A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 28+ years and have studied kinesiology and nutrition

Just wanted to add that you can use a bodybugg, which monitors body temperature with respect to ambient temperature and perspiration to calculate TDEE and I found it to be quite accurate (ie, if I ate 500 less than the number it gave me, I lost an average of a lb per week).

Also, this is a good article as to why HRMs are only good for cardio exercise! http://www.sparkpeople.com/community/ask_the_experts.asp?q=75

texasgardnr

Just starting to read, and so much to learn, so I'm bumping to return to over time.

Thank you to all who contributed :flowerforyou:

MMB5222

BethlovesRene

bump for later

Lina4Lina

I know the answer but figure if others want to give their opinion and I don't want to start a new thread:

1) Is there a danger to exercising multiple times per day (different types of exercises) if you are listening to your body AND giving specific muscle groups a couple days to recover after heavy lifting sessions?

Cheri_Moves

Dumb question...

What is "bro science"? I need to hear it from you to make sure I what I "think" it is, is correct

RATTER33

Bump Awesome!!!!

ladytinkerbell99

I am currently eating 1400 calories a day but haven't started my exercising, that starts next week, the Fat2Fit site says I should be eating 1807. Of course it says to adjust as needed so is my 400 cal deficite ok? I feel fine, only hungry once since starting and have good energy. I'm a bit confused.

Get an approximation of your TDEE and consume 20% less of it.

http://calorieline.com/tools/tdee

A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 28+ years and have studied kinesiology and nutrition

^ bump for later

ninerbuff

TDEE Questions

I recently started eating closer to my TDEE, how soon should I start to see results (substained weight loss) to know it's working?

Weight loss isn't linear, but if you are eating under your TDEE you should start seeing results in about a week or two. Sometimes faster.

If I'm calculating my TDEE to my actual activity level, then I should NOT eat back my exercise calories, right?

Correct

When I finally get a HRM, can I wear it all day for a week to get a more accurate TDEE?

Thank you!

An HRM isn't an accurate way to gauge your TDEE because all it measures is heart rate. Say you watched a scary movie or got excited about something that made your heart rate go up? Faster heart rate, but that didn't mean you actually equaled a calorie burn from exercise with the same heart rate.

A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 28+ years and have studied kinesiology and nutrition

Just wanted to add that you can use a bodybugg, which monitors body temperature with respect to ambient temperature and perspiration to calculate TDEE and I found it to be quite accurate (ie, if I ate 500 less than the number it gave me, I lost an average of a lb per week).

Also, this is a good article as to why HRMs are only good for cardio exercise! http://www.sparkpeople.com/community/ask_the_experts.asp?q=75

Agree here. I have a Bodybugg, but haven't used it as of late, however when I did it was quite accurate when I did use it................with the exception of riding on rollercoasters! Accelerometer didn't know how to calculate it accurately and gave me an 8,000 calorie burn for the day.:laugh:

A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 28+ years and have studied kinesiology and nutrition

ninerbuff

I know the answer but figure if others want to give their opinion and I don't want to start a new thread:

1) Is there a danger to exercising multiple times per day (different types of exercises) if you are listening to your body AND giving specific muscle groups a couple days to recover after heavy lifting sessions?

No danger (unless you're NOT sufficiently eating correctly and leading yourself to malnourishment) . In fact I was doing 2 a days for my own personal workouts and then instructing cardio kick boxing once a day for like 7 years straight.

A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 28+ years and have studied kinesiology and nutrition

ninerbuff

Dumb question...

What is "bro science"? I need to hear it from you to make sure I what I "think" it is, is correct

In the fitness world, it's information that's passed around from anecdotal evidence and regarded as fact. Very prevalent in body building circles of the gym.

A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 28+ years and have studied kinesiology and nutrition

ninerbuff

MUSCLE CATABOLISM There's lots of "bro science" on this, but keeping it simple and truthful, muscle catabolism becomes a concern in dieting when calories are drastically too low (VLCD) and or insufficient protein is consumed to help retain skeletal muscle.
There are many who are fixated on the number on the scale and get all giddy when scale weight goes down, but if that weight is a good portion of muscle, then they will usually end up losing weight and just looking like a smaller version of how they look now.

To help avoid it, RESISTANCE TRAINING and adequate protein intake are needed.

A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 28+ years and have studied kinesiology and nutrition

Altruista75

Certainly will be reading later!

MelBee29

keeping on file

Hendrix7

Carbs At Night
Carbs at Night: Fat loss killer or imaginary boogeyman?

]Dr. Layne Norton
PhD Nutritional Sciences

Carbs at Night: Fat loss killer or imaginary boogeyman?

There are quite a few things that everyone in the fitness industry KNOWS. You have to eat 8 meals per day, consume 400g+ protein per day, do fasted cardio, use heavy weights to bulk up, and light weights wit high reps to tone up… oh wait, those are all BROSCIENCE! Don’t get me wrong, bodybuilding and fitness have been on the cutting edge of many dietary and training interventions that mainstream science is only now catching up. Unfortunately, the vetting process for many of these protocols isn’t exactly stringent. Thus, many things become accepted as fact, when in reality they are BROSCIENCE. The debate about whether or not it’s ok to have carbs at night has been all but settled in the fitness industry. You simply can’t consume a shred of carbohydrates at night or you will store fat faster than vampire rises after the sun sets! That is, according to many fitness ‘experts’ out there, most of whose credentials are worth about as much as a thin sheet of slightly used one ply toilet paper. So Anthony Collova, owner of Broscience.com and IIFYM.com asked me to look into this fitness factoid to determine if eating carbs at night was actually detrimental to your body composition or if it was all broscience.

So where did this ‘no carbs at night’ thing come from?
In order to properly *kitten* this fitness ‘fact’ we need to understand why limiting carbs at night is recommended in the first place. Most ‘experts’ who recommend limiting carbs at night do so because their assertion is since you will be going to sleep soon, your metabolism will slow down and those carbohydrates will have a greater chance at being stored as fat compared to if they were consumed earlier in the day where they would have a greater probability of being burned. Seems reasonable, but broscience always ‘sounds’ reasonable. They also often assert that insulin sensitivity is reduced at night, shifting your carb storing directionality towards fat and away from muscle.

Let’s tackle the issue of metabolic rate slowing down at night time first. The logic behind this theory seems reasonable enough: you lie down in a bed and don’t really move, just sleep, so obviously you are burning less calories than if you are awake doing stuff, even if you are just sitting in a chair or couch resting, you have to burn more calories than just sleeping right? At first glance this seems to jive with work from Katoyose et al. which showed that energy expenditure decreased during the first half of sleep approximately 35% (1). However, these researchers did show that during the latter half of sleep energy expenditure significantly increased associated with REM sleep. So, there are rises and falls in sleeping metabolic rate (SMR), but what is the overall effect? Interestingly, at the very least it does not appear that the average overall energy expenditure during sleep is any different than resting metabolic rate (RMR) during the day (2, 3). Additionally, it appears that exercise increases sleeping metabolic rate significantly leading to greater fat oxidation during sleep (4). This seems to be in line with data from Zhang et al. which demonstrated that obese individuals had sleeping metabolic rates lower than their resting metabolic rates, whereas lean individuals had sleeping metabolic rates significantly greater than their resting metabolic rate (3). So unless you are obese, not only does your metabolism NOT slow down during sleep, it actually increases! The idea that you should avoid carbs at night because your metabolism slows down and you won’t ‘burn them off’ definitely doesn’t pass the litmus test.

So the whole ‘don’t eat carbs at night’ thing is definitely broscience right?
So far, the fear of carbs at night certainly smells like broscience, but before we render a verdict, let’s examine things further. There is also the issue of insulin sensitivity and glucose tolerance to address. This is where things get interesting. Compared to morning meals, levels of blood glucose and blood insulin definitely remain elevated longer with evening meals (5, 6). Ah ha! There it is, proof, that you shouldn’t consume carbs at night right? Not so fast. Though insulin sensitivity and glucose tolerance appear to be worse at night compared to a morning meal, it is important to keep in mind that a morning meal is after an overnight fast and the fast may improve insulin sensitivity. Perhaps a more fair comparison is a mid day meal vs. a night time meal. In this case there is actually no difference in insulin sensitivity or glucose tolerance (5). Therefore, it appears that insulin sensitivity and glucose tolerance are not necessarily impaired and night, but rather are merely enhanced by an overnight fast.

Does any of this science mumbo jumbo actually make a difference?
While it is great to talk about mechanisms and nitpick every intricate detail about metabolism, at the end of the day, we have to examine whether or not any of this stuff makes any difference. Fortunately for us, a recent study published in the Journal of Obesity examined this very question (7). These researchers from Israel put people on a calorically restricted diet for 6 months and split them into two groups, a control group and an experimental group. Each group consumed the same amount of calories, protein, carbohydrates, and fat but they distributed their carbohydrate intake very differently. One group (control) ate carbs throughout the day, whereas the experimental group consumed the majority of their carbohydrate intake (approximately 80% of the total) at the night. What they found after 6 months may shock you. Not only did the experimental group consuming the majority of their carbs at night lose significantly more weight and bodyfat than the control group, they also were better satiety and less hunger!

Whoa hold up… less hunger? I don’t buy it.
You heard me right, they were less hungry. Now I’m sure all of you that have been following typical fitness protocols where you eat 6 times per day and have most of your carbs earlier in the day are thinking “man if I went more than 2-3 hours without carbs I’d be starving!” Well my friends you are buying into a vicious cycle I’m afraid. Let me explain: when you eat small amount of carbs frequently you are basically titrating in glucose to your system. To dispose of this glucose your body releases insulin to drive blood glucose into cells. Over-secretion of insulin however may cause hunger to rise (typically about 2-3 hours post meal, the approximate time course of an insulin response), but no problem, you are eating every 2-3 hours anyway right? Just titrate in some more glucose. Unfortunately this makes you crave and consume glucose like clockwork and tricks many people into thinking that they NEED carbs every 2-3 hours or they would be hungry when in fact the opposite is true. If you ate carbs less frequently with further time between carb dosings, you would be less hungry because your own body would ramp up systems that deal with endogenous glucose production, and keep your blood glucose steady. When you consume carbs every 2-3 hours however this system of glucose production (gluconeogenesis) becomes chronically down regulated and you must rely on exogenous carb intake to maintain your blood glucose levels. Now if you transition from eating carbs every 2-3 hours to further apart for the first few days you may be hungry until your body has adjusted to using gluconeogenesis to maintain blood glucose rather than just eating carbs every 2-3 hours, but once you do adjust, you will find that you are far less hungry. Bringing things full circle, this is exactly what the researchers found! These subjects were hungrier in the first week of the diet compared to 90 and 180 days into the diet where they were much more satiated.

So what’s the explanation for the night time carb group losing more body fat and being more satiated than the control group (maybe we should call them the ‘bro’ group)? The researchers postulated that more favorable shifts in hormones may be the difference. The baseline insulin values in the experimental group eating the majority of carbs at night were significantly lower than those eating carbs during the day (7). So much for carbs at night decreasing insulin sensitivity huh? Additionally, the experimental group had much higher levels of adiponectin, a hormone associated with increased insulin sensitivity and fat burning. They also had a trend for slightly higher leptin levels. Furthermore, the night time carb munchers had lower levels of LDL (bad) cholesterol and higher levels of HDL (good) Cholesterol. Overall the people eating the majority of their carbs at night lost more bodyfat and had better markers of health by the end of the study than those who ate more of their carbs during the day time.

So what’s the verdict?
I am not ready to say that we should all be eating the majority of our carbs at night. I would like to see this study repeated but with a bolus amount of carbs eaten at one meal in the morning to properly compare it to the single high carb meal at night, whereas the previous study compared a bolus night time carb meal vs. several feedings of carbs throughout the day. It may very well be that the beneficial effects of the diet in this study was more associated with limiting carb dosing (and insulin secretion) to a single bolus rather than spreading them throughout the day. However, I think what can be said with relative certainly is the notion that consuming carbohydrates at night will lead to more fat gain, or impair fat loss compared to consuming them at other times of the day. So write it down “Don’t eat carbs at night bro” has officially been BUSTED as BROSCIENCE!

Literature Cited
1. Katayose Y, Tasaki M, Ogata H, Nakata Y, Tokuyama K, Satoh M. Metabolic rate and fuel utilization during sleep assessed by whole-body indirect calorimetry. Metabolism. 2009 Jul;58(7):920-6.
2. Seale JL, Conway JM. Relationship between overnight energy expenditure and BMR measured in a room-sized calorimeter. Eur J Clin Nutr. 1999 Feb;53(2):107-11.
3. Zhang K, Sun M, Werner P, Kovera AJ, Albu J, Pi-Sunyer FX, Boozer CN. Sleeping metabolic rate in relation to body mass index and body composition. Int J Obes Relat Metab Disord. 2002 Mar;26(3):376-83.
4. Mischler I, Vermorel M, Montaurier C, Mounier R, Pialoux V, Pequignot JM, Cottet-Emard JM, Coudert J, Fellmann N. Prolonged daytime exercise repeated over 4 days increases sleeping heart rate and metabolic rate. Can J Appl Physiol. 2003 Aug;28(4):616-29.
5. Biston P, Van Cauter E, Ofek G, Linkowski P, Polonsky KS, Degaute JP. Diurnal variations in cardiovascular function and glucose regulation in normotensive humans. Hypertension. 1996 Nov;28(5):863-71.
6. Van Cauter E, Shapiro ET, Tillil H, Polonsky KS. Circadian modulation of glucose and insulin responses to meals: Relationship to cortisol rhythm. Am J Physiol. 1992 Apr;262(4 Pt 1):E467-75.
7. Sofer S, Eliraz A, Kaplan S, Voet H, Fink G, Kima T, Madar Z. Greater weight loss and hormonal changes after 6 months diet with carbohydrates eaten mostly at dinner. Obesity (Silver Spring). 2011 Oct;19(10):2006-14.

Hendrix7

Is there a limit to how much protein the body can use in a single meal?
Alan Aragon

Introduction

A longstanding belief in fitness circles is that the body can only use a certain amount of protein per meal, and the excess is either oxidized or excreted. The ballpark range thrown around is 20-30 grams, with 30 grams being perhaps the most common figure.

This guideline has led many trainees to go through the pains of consuming multiple doses of protein throughout the day, banking that it will maximize muscle anabolism or muscle retention.

Well, true or not, this concept fits in nicely with another longstanding fitness “rule” that you have to eat at least six times per day in order to keep the body’s metabolism revving high. Since the meal frequency and metabolism dogma has been thoroughly debunked [1-5], it’s time to dig into the topic of whether there’s a limit to effective protein dosing, and if so, what that limit might be.

Looking at simple logic first

Let’s imagine an experiment involving two relatively lean 200 lb individuals. For the purposes of this illustration, I’ll assign a daily amount of protein known to adequately support the needs of the athletic population. We’ll give Person A 150 g protein spread over five meals at 30 g each. We’ll give Person B the same amount of protein, but in a single meal. Let’s say that this meal consists of a 16 oz steak, chased with a shake containing two scoops of protein powder.

If we really believed that only 30 g protein can be handled by the body in a single meal, then Person B would eventually run into protein deficiency symptoms because he supposedly is only absorbing a total of 30 g out of the 150 g we’re giving him. At 30 g/day, he’s only getting 0.33 g/kg of bodyweight, which isn’t even half of the already-low RDA of 0.8 g/kg. If the body worked this way, the human species would have quickly become extinct. The human body is more efficient and effective than we give it credit for.

The body will take all the sweet time it needs to effectively digest and absorb just about whatever dose you give it. Person A will have shorter digestion periods per meal in order to effectively absorb and utilize the small meals. Person B will have a longer digestion period in order to effectively absorb and utilize the large meal. While the truth in this logic seems self-evident, the important question is whether or not it’s supported by scientific research. Let’s look at the evidence, starting with immediate-effect (acute) studies, then move on to the longer-term trials.

Research examining speed of absorption

A thorough literature review by Bilsborough and Mann compiled data from studies by various investigators who measured the absorption rates of various protein sources [6]. Oddly, an amino acid mixture designed to mimic the composition of pork tenderloin made the top spot, at 10 g/hour, while whey took a close second at 8-10 g/hour. Other proteins fell in their respective spots below the top two, with little rhyme or reason behind the outcomes. As a matter of trivia, raw egg protein was the most slowly absorbed of them all at 1.3 g/hour.

It’s important to note that these data have some serious limitations. A major one is the variance of the methods used to determine the absorption rates (i.e., intravenous infusion, oral ingestion, ileal ingestion). Most of the methods are just too crude or far-fetched for serious consideration. Another limitation is that these figures could be skewed depending upon their concentration in solution, which can affect their rate of gastric evacuation. Another factor to consider is the timing of ingestion relative to exercise and how that might differentially affect absorption rates. Finally, short-term data leaves a lot open to question.

Short-term research supporting the magic limit

I’ve heard many folks parrot that the maximal anabolic effect of a single protein dose is limited to 20 grams, citing recent work by Moore and colleagues [7]. In this study’s 4-hour post-exercise test period, 40 g protein did not elicit a greater anabolic response than 20 g. I’d interpret these outcomes with caution. Fundamentally speaking, protein utilization can differ according to muscle mass. The requirements of a 140-lb person will differ markedly from someone who’s a lean 200. Additionally, a relatively low amount of total volume was used (12 sets total). Typical training bouts usually involve more than one muscle group and are commonly at least double that volume, which can potentially increase the demand for nutrient uptake. Finally, the conclusion of the authors is questionable. They state explicitly,

“…we speculate that no more than 5-6 times daily could one ingest this amount (~20 g) of protein and expect muscle protein synthesis to be maximally stimulated.”

So, they’re implying that 100-120 grams of protein per day is maximal for promoting muscle growth. Wait a minute, what? Based on both the bulk of the research evidence and numerous field observations, this is simply false [8,9].

In another recent study, Symons and colleagues compared the 5-hour response of a moderate serving of lean beef containing 30 g protein with a large serving containing 90 g protein [10]. The smaller serving increased protein synthesis by approximately 50%, and the larger serving caused no further increase in protein synthesis, despite being triple the dose. The researchers concluded that the ingestion of more than 30 g protein in a single meal does not further enhance muscle protein synthesis. While their conclusion indeed supports the outcomes of their short-term study, it’s pretty easy to predict the outcomes in muscle size and strength if we compared a total daily protein dose of 90 g with 30 g over a longer trial period, let alone one involving a structured exercise protocol. This brings me to the crucial point that acute outcomes merely provide grounds for hypothesis. It’s not completely meaningless, but it’s far from conclusive without examining the long-term effects.

Longer-term research challenging the magic limit

If we were to believe the premise that a 20-30 g dose of protein yields a maximal anabolic effect, then it follows that any excess beyond this dose would be wasted. On the contrary, the body is smarter than that. In a 14-day trial, Arnal and colleagues found no difference in fat-free mass or nitrogen retention between consuming 79% of the day’s protein needs (roughly 54 g) in one meal, versus the same amount spread across four meals [11].

Notably, this study was done on young female adults whose fat-free mass averaged 40.8 kg (89.8 lb). Considering that most non-sedentary males have considerably more lean mass than the female subjects used in the aforementioned trial, it’s plausible that much more than 54 g protein in a single meal can be efficiently processed for anabolic and/or anti-catabolic purposes. If we extrapolated the protein dose used in this study (79% of 1.67g/kg) to the average adult male, it would be roughly 85-95 g or even more, depending on just how close someone is to the end of the upper limits of muscular size.

When Arnal and colleagues applied the same protocol to the elderly population, the single-dose treatment actually caused better muscle protein retention than the multiple-dose treatment [12]. This raises the possibility that as we age, larger protein feedings might be necessary to achieve the same effect on protein retention as lesser amounts in our youth.

IF research nailing the coffin shut?

Perhaps the strongest case against the idea of a dosing limit beyond which anabolism or muscle retention can occur is the recent intermittent fasting (IF) research, particularly the trials with a control group on a conventional diet. For example, Soeters and colleagues compared two weeks of IF involving 20-hour fasting cycles with a conventional diet [13]. Despite the IF group’s consumption of an average of 101 g protein in a 4-hour window, there was no difference in preservation of lean mass and muscle protein between groups.
In another example, Stote and colleagues actually reported an improvement in body composition (including an increase in lean mass) after 8 weeks in the IF group consuming one meal per day, where roughly 86 g protein was ingested in a 4-hour window [14]. Interestingly, the conventional group consuming three meals spread throughout the day showed no significant body composition improvements.

Keep in mind that bioelectrical impedance (BIA) was used to determine body composition, so these outcomes should be viewed with caution. I’ve been highly critical of this study in the past, and I still am. Nevertheless, it cannot be completely written off and must be factored into the body of evidence against the idea of a magic protein dose limit.

Conclusion & application

Based on the available evidence, it’s false to assume that the body can only use a certain amount of protein per meal. Studies examining short-term effects have provided hints towards what might be an optimal protein dose for maximizing anabolism, but trials drawn out over longer periods haven’t supported this idea. So, is there a limit to how much protein per meal can be effectively used? Yes there is, but this limit is likely similar to the amount that’s maximally effective in an entire day. What’s the most protein that the body can effectively use in an entire day? The short answer is, a lot more than 20-30 g. The long answer is, it depends on several factors. In most cases it’s not too far from a gram per pound in drug-free trainees, given that adequate total calories are provided [8,9].

In terms of application, I’ve consistently observed the effectiveness of having approximately a quarter of your target bodyweight in both the pre- and post-exercise meal. Note: target bodyweight is a surrogate index of lean mass, and I use that to avoid making skewed calculations in cases where individuals are markedly over- or underweight. This dose surpasses the amounts seen to cause a maximal anabolic response but doesn’t impinge upon the rest of the day’s protein allotment, which can be distributed as desired. On days off from training, combine or split up your total protein allotment according to your personal preference and digestive tolerance. I realize that freedom and flexibility are uncommon terms in physique culture, but maybe it’s time for a paradigm shift.

In sum, view all information – especially gym folklore and short-term research – with caution. Don’t buy into the myth that protein won’t get used efficiently unless it’s dosed sparingly throughout the day. Hopefully, future research will definitively answer how different dosing schemes with various protein types affect relevant endpoints such as size and strength. In the mean time, feel free to eat the whole steak and drink the whole shake, and if you want to get the best bang for your buck, go for a quality protein blend such as Nitrean!

Written By Alan Aragon
About Alan Aragon

Alan Aragon has over 15 years of success in the fitness field. He earned his Bachelor and Master of Science in Nutrition with top honors. Alan is a continuing education provider for the Commission on Dietetic Registration, National Academy of Sports Medicine, American Council on Exercise, and National Strength & Conditioning Association. Alan recently lectured to clinicians at the FDA and the annual conference of the Los Angeles Dietetic Association.

He maintains a private practice designing programs for recreational, Olympic, and professional athletes, including the Los Angeles Lakers, Los Angeles Kings, and Anaheim Mighty Ducks. Alan is a contributing editor and Weight Loss Coach of Men’s Health magazine.

His book Girth Control is considered one of the most in-depth manuals for physique improvement and understanding nutrition for fitness & sports. Last but not least, Alan writes a monthly research review providing of the latest science on nutrition, training, and supplementation. Visit Alan’s blog to keep up with his latest shenanigans.



References

1. Smeets AJ, Westerterp-Plantenga MS. Acute effects on metabolism and appetite profile of one meal difference in the lower range of meal frequency. Br J Nutr. 2008 Jun;99(6):1316-21.

2. Taylor MA, Garrow JS. Compared with nibbling, neither gorging nor a morning fast affect short-term energy balance in obese patients in a chamber calorimeter. Int J Obes Relat Metab Disord. 2001 Apr;25(4):519-28.

3. Bellisle F, McDevitt R, Prentice AM. Meal frequency and energy balance. Br J Nutr. 1997 Apr;77 Suppl 1:S57-70.

4. Verboeket-van de Venne WP, Westerterp KR. Frequency of feeding, weight reduction and energy metabolism. Int J Obes Relat Metab Disord. 1993 Jan;17(1):31-6.

5. Verboeket-van de Venne WP, Westerterp KR. Influence of the feeding frequency on nutrient utilization in man: consequences for energy metabolism. Eur J Clin Nutr. 1991 Mar;45(3):161-9.

6. Bilsborough S, Mann N. A review of issues of dietary protein intake in humans. Int J Sport Nutr Exerc Metab. 2006 Apr;16(2):129-52.

7. Moore DR, et al. Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. Am J Clin Nutr. 2009 Jan;89(1):161-8.

8. Campbell B, et al. International Society of Sports Nutrition position stand: protein and exercise. J Int Soc Sports Nutr. 2007 Sep 26;4:8.

9. Tipton KD, Wolfe RR. Protein and amino acids for athletes. J Sports Sci. 2004 Jan;22(1):65-79.

10. Symons TB, et al. A moderate serving of high-quality protein maximally stimulates skeletal muscle protein synthesis in young and elderly subjects. J Am Diet Assoc. 2009 Sep;109(9):1582-6.

11. Arnal MA, et al. Protein feeding pattern does not affect protein retention in young women. J Nutr. 2000 Jul;130(7):1700-4.

12. Arnal MA, et al. Protein pulse feeding improves protein retention in elderly women. Am J Clin Nutr. 1999 Jun;69(6):1202-8.

13. Soeters MR, et al. Intermittent fasting does not affect whole-body glucose, lipid, or protein metabolism. Am J Clin Nutr. 2009 Nov;90(5):1244-51.

14. Stote KS, et al. A controlled trial of reduced meal frequency without caloric restriction in healthy, normal-weight, middle-aged adults. Am J Clin Nutr. 2007 Apr;85(4):981-8.

ninerbuff

Carbs At Night
Carbs at Night: Fat loss killer or imaginary boogeyman?

]Dr. Layne Norton
PhD Nutritional Sciences

Carbs at Night: Fat loss killer or imaginary boogeyman?

There are quite a few things that everyone in the fitness industry KNOWS. You have to eat 8 meals per day, consume 400g+ protein per day, do fasted cardio, use heavy weights to bulk up, and light weights wit high reps to tone up… oh wait, those are all BROSCIENCE! Don’t get me wrong, bodybuilding and fitness have been on the cutting edge of many dietary and training interventions that mainstream science is only now catching up. Unfortunately, the vetting process for many of these protocols isn’t exactly stringent. Thus, many things become accepted as fact, when in reality they are BROSCIENCE. The debate about whether or not it’s ok to have carbs at night has been all but settled in the fitness industry. You simply can’t consume a shred of carbohydrates at night or you will store fat faster than vampire rises after the sun sets! That is, according to many fitness ‘experts’ out there, most of whose credentials are worth about as much as a thin sheet of slightly used one ply toilet paper. So Anthony Collova, owner of Broscience.com and IIFYM.com asked me to look into this fitness factoid to determine if eating carbs at night was actually detrimental to your body composition or if it was all broscience.

So where did this ‘no carbs at night’ thing come from?
In order to properly *kitten* this fitness ‘fact’ we need to understand why limiting carbs at night is recommended in the first place. Most ‘experts’ who recommend limiting carbs at night do so because their assertion is since you will be going to sleep soon, your metabolism will slow down and those carbohydrates will have a greater chance at being stored as fat compared to if they were consumed earlier in the day where they would have a greater probability of being burned. Seems reasonable, but broscience always ‘sounds’ reasonable. They also often assert that insulin sensitivity is reduced at night, shifting your carb storing directionality towards fat and away from muscle.

Let’s tackle the issue of metabolic rate slowing down at night time first. The logic behind this theory seems reasonable enough: you lie down in a bed and don’t really move, just sleep, so obviously you are burning less calories than if you are awake doing stuff, even if you are just sitting in a chair or couch resting, you have to burn more calories than just sleeping right? At first glance this seems to jive with work from Katoyose et al. which showed that energy expenditure decreased during the first half of sleep approximately 35% (1). However, these researchers did show that during the latter half of sleep energy expenditure significantly increased associated with REM sleep. So, there are rises and falls in sleeping metabolic rate (SMR), but what is the overall effect? Interestingly, at the very least it does not appear that the average overall energy expenditure during sleep is any different than resting metabolic rate (RMR) during the day (2, 3). Additionally, it appears that exercise increases sleeping metabolic rate significantly leading to greater fat oxidation during sleep (4). This seems to be in line with data from Zhang et al. which demonstrated that obese individuals had sleeping metabolic rates lower than their resting metabolic rates, whereas lean individuals had sleeping metabolic rates significantly greater than their resting metabolic rate (3). So unless you are obese, not only does your metabolism NOT slow down during sleep, it actually increases! The idea that you should avoid carbs at night because your metabolism slows down and you won’t ‘burn them off’ definitely doesn’t pass the litmus test.

So the whole ‘don’t eat carbs at night’ thing is definitely broscience right?
So far, the fear of carbs at night certainly smells like broscience, but before we render a verdict, let’s examine things further. There is also the issue of insulin sensitivity and glucose tolerance to address. This is where things get interesting. Compared to morning meals, levels of blood glucose and blood insulin definitely remain elevated longer with evening meals (5, 6). Ah ha! There it is, proof, that you shouldn’t consume carbs at night right? Not so fast. Though insulin sensitivity and glucose tolerance appear to be worse at night compared to a morning meal, it is important to keep in mind that a morning meal is after an overnight fast and the fast may improve insulin sensitivity. Perhaps a more fair comparison is a mid day meal vs. a night time meal. In this case there is actually no difference in insulin sensitivity or glucose tolerance (5). Therefore, it appears that insulin sensitivity and glucose tolerance are not necessarily impaired and night, but rather are merely enhanced by an overnight fast.

Does any of this science mumbo jumbo actually make a difference?
While it is great to talk about mechanisms and nitpick every intricate detail about metabolism, at the end of the day, we have to examine whether or not any of this stuff makes any difference. Fortunately for us, a recent study published in the Journal of Obesity examined this very question (7). These researchers from Israel put people on a calorically restricted diet for 6 months and split them into two groups, a control group and an experimental group. Each group consumed the same amount of calories, protein, carbohydrates, and fat but they distributed their carbohydrate intake very differently. One group (control) ate carbs throughout the day, whereas the experimental group consumed the majority of their carbohydrate intake (approximately 80% of the total) at the night. What they found after 6 months may shock you. Not only did the experimental group consuming the majority of their carbs at night lose significantly more weight and bodyfat than the control group, they also were better satiety and less hunger!

Whoa hold up… less hunger? I don’t buy it.
You heard me right, they were less hungry. Now I’m sure all of you that have been following typical fitness protocols where you eat 6 times per day and have most of your carbs earlier in the day are thinking “man if I went more than 2-3 hours without carbs I’d be starving!” Well my friends you are buying into a vicious cycle I’m afraid. Let me explain: when you eat small amount of carbs frequently you are basically titrating in glucose to your system. To dispose of this glucose your body releases insulin to drive blood glucose into cells. Over-secretion of insulin however may cause hunger to rise (typically about 2-3 hours post meal, the approximate time course of an insulin response), but no problem, you are eating every 2-3 hours anyway right? Just titrate in some more glucose. Unfortunately this makes you crave and consume glucose like clockwork and tricks many people into thinking that they NEED carbs every 2-3 hours or they would be hungry when in fact the opposite is true. If you ate carbs less frequently with further time between carb dosings, you would be less hungry because your own body would ramp up systems that deal with endogenous glucose production, and keep your blood glucose steady. When you consume carbs every 2-3 hours however this system of glucose production (gluconeogenesis) becomes chronically down regulated and you must rely on exogenous carb intake to maintain your blood glucose levels. Now if you transition from eating carbs every 2-3 hours to further apart for the first few days you may be hungry until your body has adjusted to using gluconeogenesis to maintain blood glucose rather than just eating carbs every 2-3 hours, but once you do adjust, you will find that you are far less hungry. Bringing things full circle, this is exactly what the researchers found! These subjects were hungrier in the first week of the diet compared to 90 and 180 days into the diet where they were much more satiated.

So what’s the explanation for the night time carb group losing more body fat and being more satiated than the control group (maybe we should call them the ‘bro’ group)? The researchers postulated that more favorable shifts in hormones may be the difference. The baseline insulin values in the experimental group eating the majority of carbs at night were significantly lower than those eating carbs during the day (7). So much for carbs at night decreasing insulin sensitivity huh? Additionally, the experimental group had much higher levels of adiponectin, a hormone associated with increased insulin sensitivity and fat burning. They also had a trend for slightly higher leptin levels. Furthermore, the night time carb munchers had lower levels of LDL (bad) cholesterol and higher levels of HDL (good) Cholesterol. Overall the people eating the majority of their carbs at night lost more bodyfat and had better markers of health by the end of the study than those who ate more of their carbs during the day time.

So what’s the verdict?
I am not ready to say that we should all be eating the majority of our carbs at night. I would like to see this study repeated but with a bolus amount of carbs eaten at one meal in the morning to properly compare it to the single high carb meal at night, whereas the previous study compared a bolus night time carb meal vs. several feedings of carbs throughout the day. It may very well be that the beneficial effects of the diet in this study was more associated with limiting carb dosing (and insulin secretion) to a single bolus rather than spreading them throughout the day. However, I think what can be said with relative certainly is the notion that consuming carbohydrates at night will lead to more fat gain, or impair fat loss compared to consuming them at other times of the day. So write it down “Don’t eat carbs at night bro” has officially been BUSTED as BROSCIENCE!

Literature Cited
1. Katayose Y, Tasaki M, Ogata H, Nakata Y, Tokuyama K, Satoh M. Metabolic rate and fuel utilization during sleep assessed by whole-body indirect calorimetry. Metabolism. 2009 Jul;58(7):920-6.
2. Seale JL, Conway JM. Relationship between overnight energy expenditure and BMR measured in a room-sized calorimeter. Eur J Clin Nutr. 1999 Feb;53(2):107-11.
3. Zhang K, Sun M, Werner P, Kovera AJ, Albu J, Pi-Sunyer FX, Boozer CN. Sleeping metabolic rate in relation to body mass index and body composition. Int J Obes Relat Metab Disord. 2002 Mar;26(3):376-83.
4. Mischler I, Vermorel M, Montaurier C, Mounier R, Pialoux V, Pequignot JM, Cottet-Emard JM, Coudert J, Fellmann N. Prolonged daytime exercise repeated over 4 days increases sleeping heart rate and metabolic rate. Can J Appl Physiol. 2003 Aug;28(4):616-29.
5. Biston P, Van Cauter E, Ofek G, Linkowski P, Polonsky KS, Degaute JP. Diurnal variations in cardiovascular function and glucose regulation in normotensive humans. Hypertension. 1996 Nov;28(5):863-71.
6. Van Cauter E, Shapiro ET, Tillil H, Polonsky KS. Circadian modulation of glucose and insulin responses to meals: Relationship to cortisol rhythm. Am J Physiol. 1992 Apr;262(4 Pt 1):E467-75.
7. Sofer S, Eliraz A, Kaplan S, Voet H, Fink G, Kima T, Madar Z. Greater weight loss and hormonal changes after 6 months diet with carbohydrates eaten mostly at dinner. Obesity (Silver Spring). 2011 Oct;19(10):2006-14.

Layne Norton has written many great articles when it comes to countering a lot of bro science. Thanks for the contribution.

A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 28+ years and have studied kinesiology and nutrition

autumnk921

Bumping for info later & saving in my favs!! Great topic - I think a whole lot of us need this.. Thanks :happy:

jmuller06

*BUMP* A lot of great information here - thanks everyone.

NativeCoastiesTime

Bump...Thank you ninerbuff!!!