Flexibility of Intermittent Fasting
- Thread starter colby2152
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Bumping in with a working theory on combining IF and low carb eating regimen.
If we eat carbs directly after workout during the supercompensation window, and then wait until the insulin levels drop (approx. 4-5 h after last meal, including digestion and depostion of nutrients into cells) and then go on a low carb regimen, wouldn't this be interpreted by the body as a fast (I don't remember where I read of this)?
The trick is when coming off low-carbs, as the digestion of fats and protein takes a lot longer (perhaps 5-6 hours) before they are cleared out of the way. There migth be some idea to cut down on fats and only eat protein during this period (we wouldn't want to stuff ourselfes with carbohydrates with our bellies full of fat ready to be stored away in the fat cells as insulin kicks in). 5-6 hours after our last fat meal this would be a nice window of opportunity to ingest some carbs and protein (preferrably essential amino acids) before hitting the gym, to halt the catabolic effect from cortisol. Then we can indulge ourselfes with some large carb+protein meals (minimum fat). But only enough to refill our supplies of glycogen in the muscles. We might get some glycogen deposited in the liver to be redistributed when blood glucose levels drop, but it won't last longer than 12-16 hours (if full).
On non-workout days, we continue eating low-carb. Because fat is digested so slowly we won't get as hungry as during a complete fasting diet, if we were to cut some calories out. A calorie surplus on workout days and a deficit on non-workout days might both build mass and cut of fat.
I know protein do increase insulin levels to some extent, so we must be careful not to overindulge ourselfes or it will throw of the effect of fasting.
This differs from the CKD and such, by being performed in mini-cycles during the week by using a minor supercompensation after every workout (if the workout was taxing enough) similar to IF. We won't get much ketone bodies flowing around either as the time span is so short. It differs from IF, becase you are actually eating something (but not carbs).
Is the reasoning sound or is there some issues I have missed in the equation? Or, have you heard of something similar before? I'm still trying to put the pieces together.
If we eat carbs directly after workout during the supercompensation window, and then wait until the insulin levels drop (approx. 4-5 h after last meal, including digestion and depostion of nutrients into cells) and then go on a low carb regimen, wouldn't this be interpreted by the body as a fast (I don't remember where I read of this)?
The trick is when coming off low-carbs, as the digestion of fats and protein takes a lot longer (perhaps 5-6 hours) before they are cleared out of the way. There migth be some idea to cut down on fats and only eat protein during this period (we wouldn't want to stuff ourselfes with carbohydrates with our bellies full of fat ready to be stored away in the fat cells as insulin kicks in). 5-6 hours after our last fat meal this would be a nice window of opportunity to ingest some carbs and protein (preferrably essential amino acids) before hitting the gym, to halt the catabolic effect from cortisol. Then we can indulge ourselfes with some large carb+protein meals (minimum fat). But only enough to refill our supplies of glycogen in the muscles. We might get some glycogen deposited in the liver to be redistributed when blood glucose levels drop, but it won't last longer than 12-16 hours (if full).
On non-workout days, we continue eating low-carb. Because fat is digested so slowly we won't get as hungry as during a complete fasting diet, if we were to cut some calories out. A calorie surplus on workout days and a deficit on non-workout days might both build mass and cut of fat.
I know protein do increase insulin levels to some extent, so we must be careful not to overindulge ourselfes or it will throw of the effect of fasting.
This differs from the CKD and such, by being performed in mini-cycles during the week by using a minor supercompensation after every workout (if the workout was taxing enough) similar to IF. We won't get much ketone bodies flowing around either as the time span is so short. It differs from IF, becase you are actually eating something (but not carbs).
Is the reasoning sound or is there some issues I have missed in the equation? Or, have you heard of something similar before? I'm still trying to put the pieces together.
<div></div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE">If we eat carbs directly after workout during the supercompensation window, and then wait until the insulin levels drop (approx. 4-5 h after last meal, including digestion and depostion of nutrients into cells) and then go on a low carb regimen, wouldn't this be interpreted by the body as a fast (I don't remember where I read of this)? </div>
That is a sound theory, but I still cannot consider a fast being five hours. Interesting idea on how to take the low carb approach with IF, but a better idea would be to fast for eight hours, then go into a PSMF mode for another eight hours. The last eight hours is the refeed portion.
That is a sound theory, but I still cannot consider a fast being five hours. Interesting idea on how to take the low carb approach with IF, but a better idea would be to fast for eight hours, then go into a PSMF mode for another eight hours. The last eight hours is the refeed portion.
There is one difference - on non-workout days, there is no carb-up, so the low-carb/cutting/"fasting" continues...
TunnelRat
Active Member
<div>
(nkl @ Mar. 04 2008,08:00)</div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE">and then go on a low carb regimen</div>
Although I am not completely ignorant of such things, yet I am dangerously close to being so. Would you be so gracious as to define "low carb regimen"? I want to make sure I am on the same page.
For the past several months I've been ingesting well less than 1 gram of carbs per lb of bodyweight (weighing less than 140 lbs). Often I consume less than 100 grams of carbs per day. Only rarely have I come even close to 200 grams.
(nkl @ Mar. 04 2008,08:00)</div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE">and then go on a low carb regimen</div>
Although I am not completely ignorant of such things, yet I am dangerously close to being so. Would you be so gracious as to define "low carb regimen"? I want to make sure I am on the same page.
For the past several months I've been ingesting well less than 1 gram of carbs per lb of bodyweight (weighing less than 140 lbs). Often I consume less than 100 grams of carbs per day. Only rarely have I come even close to 200 grams.
bluejacket
New Member
im not sure 100% on what your proposing.
most real effective IF plans ive seen (for cuttting, recomp) involve what your talking about. serious cals (and carbs) just before and the hrs following a w/o. non w/o days have a signif. deficit with fat still low/modest and carbs low(ish)......perhaps even some cardio.
are you thinking of non-IF style eating on non-w/o days just as long as its low-carb?
i think it could work......but then again if youve seen my prev. posts i think just about anything could work so long as it fits your lifestyle.
a lot of differant factors can go into what makes a workable IF style eating and w/o plan.
how many days you lift -vs- how many off days (how that can effect weekly cal + or -).
how you feel (and work) on a fast.
goals (cut, recomp,bulk,maint).
how you handle and react to carbs. etc etc etc.
almost every IF plan ive seen folks come up with has been modified (from where they got it) to fit preferences, lifestyle etc. personally i eat too many of my cals pre-w/o but given my sched its unavoidable, unless i want to stay up to 2AM on w/o days. some folks like to have a little protein in the AM or even a small meal to help with hunger. whatever helps smooth out the tough spots and keeps you on the diet is a good idea...........as long as your still basically eating for you goals.
as far as the IF on w/o days only idea (if that is what your saying) personally i dont care for it. fasting each day is not hard ( for me) b/c im used to it. the only real tough times ive had have been days following a holiday or other "reason" for eating normal (br,lunch,dinner).
good luck
most real effective IF plans ive seen (for cuttting, recomp) involve what your talking about. serious cals (and carbs) just before and the hrs following a w/o. non w/o days have a signif. deficit with fat still low/modest and carbs low(ish)......perhaps even some cardio.
are you thinking of non-IF style eating on non-w/o days just as long as its low-carb?
i think it could work......but then again if youve seen my prev. posts i think just about anything could work so long as it fits your lifestyle.
a lot of differant factors can go into what makes a workable IF style eating and w/o plan.
how many days you lift -vs- how many off days (how that can effect weekly cal + or -).
how you feel (and work) on a fast.
goals (cut, recomp,bulk,maint).
how you handle and react to carbs. etc etc etc.
almost every IF plan ive seen folks come up with has been modified (from where they got it) to fit preferences, lifestyle etc. personally i eat too many of my cals pre-w/o but given my sched its unavoidable, unless i want to stay up to 2AM on w/o days. some folks like to have a little protein in the AM or even a small meal to help with hunger. whatever helps smooth out the tough spots and keeps you on the diet is a good idea...........as long as your still basically eating for you goals.
as far as the IF on w/o days only idea (if that is what your saying) personally i dont care for it. fasting each day is not hard ( for me) b/c im used to it. the only real tough times ive had have been days following a holiday or other "reason" for eating normal (br,lunch,dinner).
good luck
Low carb for me is 30-50 grams of carbs a day (lower is hard to maintain). Studies have shown that the less carbs we ingest the more fat loss w/o loss of lean mass is possible. The brain needs approx 104 grams of glucose a day and thus we need to supply this in the form of protein (unless we have been running on ketones for a while and there is only a 25% need for glucose). Protein gives, through gluconeogenesis, approx. 58% glucose. Fat also gives a 10% from the conversion of glycerol. So there must be at least so much protein in our diet to compensate for the difference between carbs and what the brain needs. Otherwise we are eating ourselfes, so to speak. Then, depending on goal, the rest of the calories are added by fat. We also need some extra protein to provide for protein synthesis.
The mini-cycles with eating above maint. and then eating below maint. prevent metabolism from dropping to far (and thus stalling the fat loss). From the studies I have seen there is a approx. 55% vs 45% gain of lean mass vs. fat when bulking, and combined with the more than 90% shedding of fat on a 30 gram carb diet, we must find a balance between bulking and cutting. A 50-50 bulking and cutting regimen (equal surplus and deficit on alternating days) would work in theory with the numbers above. No net weight gain, but a gradual shift of body composition due fat loss and lbm gain. There is no absolutes, as our bodies react differently from time to time and from person to person and the varying daily activity level, etc.
The problem with IFs, I believe, is that because it's a non-ketogenic diet, protein losses can be great if we do not compensate with protein from diet (which is hard if we are not eating). Ideally we would use a ketogenic diet to prevent protein losses but this is not compatible with serious weight lifting.
Some backstory: I was on a low carb diet for roughly a year and it was working fine, although I lost a little to much lean mass and was starting to gain some fat due to low metabolism. Then I started working out seriously again (been off for a couple of years) to compensate and read Lyle's writings and tried to make something useful of it. I went on and off low carb and hi carb for some time but noticed an unwelcome fat gain (mostly from overdoing the hi carbs). It worked well, but it was not perfect. Then I tried a hi carb - low fat regimen, but gained more fat (and water). I have been pondering for some time on how to make this work (gaining mass w/o fat gain). I've read Ori Hofmekler's Max Muscle Min Fat a while back so I knew there was some point in doing the cycles on a daily basis, but I thought it would be hard to eat above maintance during such a short time as 4 hours (as Ori uses). Using low carb to substitute fasting would make this more feasable. I'll give this a try to see of it works.
I know John Berardi's Precision Nutrition is also close to the mark - carbs only after workouts. As is Lyle's TKDs (targeted ketogenic diet).
The mini-cycles with eating above maint. and then eating below maint. prevent metabolism from dropping to far (and thus stalling the fat loss). From the studies I have seen there is a approx. 55% vs 45% gain of lean mass vs. fat when bulking, and combined with the more than 90% shedding of fat on a 30 gram carb diet, we must find a balance between bulking and cutting. A 50-50 bulking and cutting regimen (equal surplus and deficit on alternating days) would work in theory with the numbers above. No net weight gain, but a gradual shift of body composition due fat loss and lbm gain. There is no absolutes, as our bodies react differently from time to time and from person to person and the varying daily activity level, etc.
The problem with IFs, I believe, is that because it's a non-ketogenic diet, protein losses can be great if we do not compensate with protein from diet (which is hard if we are not eating). Ideally we would use a ketogenic diet to prevent protein losses but this is not compatible with serious weight lifting.
Some backstory: I was on a low carb diet for roughly a year and it was working fine, although I lost a little to much lean mass and was starting to gain some fat due to low metabolism. Then I started working out seriously again (been off for a couple of years) to compensate and read Lyle's writings and tried to make something useful of it. I went on and off low carb and hi carb for some time but noticed an unwelcome fat gain (mostly from overdoing the hi carbs). It worked well, but it was not perfect. Then I tried a hi carb - low fat regimen, but gained more fat (and water). I have been pondering for some time on how to make this work (gaining mass w/o fat gain). I've read Ori Hofmekler's Max Muscle Min Fat a while back so I knew there was some point in doing the cycles on a daily basis, but I thought it would be hard to eat above maintance during such a short time as 4 hours (as Ori uses). Using low carb to substitute fasting would make this more feasable. I'll give this a try to see of it works.
I know John Berardi's Precision Nutrition is also close to the mark - carbs only after workouts. As is Lyle's TKDs (targeted ketogenic diet).
bluejacket
New Member
<div>
(TunnelRat @ Mar. 04 2008,11:45)</div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE"><div>
(nkl @ Mar. 04 2008,08:00)</div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE">and then go on a low carb regimen</div>
Although I am not completely ignorant of such things, yet I am dangerously close to being so. Would you be so gracious as to define "low carb regimen"? I want to make sure I am on the same page.
For the past several months I've been ingesting well less than 1 gram of carbs per lb of bodyweight (weighing less than 140 lbs). Often I consume less than 100 grams of carbs per day. Only rarely have I come even close to 200 grams.</div>
to answer your question i think it means diff. things to diff. folks and even that changes over time.
basic PSMF (as low/no carb as you can get)typically still has 10-30g of tag along carbs in it depending on food choices.
many low carb strategies use less then 20-25% of cal intake or 50-80g depending on bodywgt, cal level, tolerance etc.
for some (perhaps yourself) with little to no exper. with low carb. it can mean the 1g per lb of bw. or in that range. its all relative to where your coming from anyway.
from my past exper........i didnt have the success i was looking for in cutting until i limited carbs. at the time that meant down to 100-120g a day. over time i moved to UD 2.0 which had periods of @50g per day. i tried some PSMF for a bit but found that carb level a bit too low for me. of course by then 100g of carbs in (diet) day seemed like a binge.........its all relative.
anyway, thats my 2cents
good luck
(TunnelRat @ Mar. 04 2008,11:45)</div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE"><div>
(nkl @ Mar. 04 2008,08:00)</div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE">and then go on a low carb regimen</div>
Although I am not completely ignorant of such things, yet I am dangerously close to being so. Would you be so gracious as to define "low carb regimen"? I want to make sure I am on the same page.
For the past several months I've been ingesting well less than 1 gram of carbs per lb of bodyweight (weighing less than 140 lbs). Often I consume less than 100 grams of carbs per day. Only rarely have I come even close to 200 grams.</div>
to answer your question i think it means diff. things to diff. folks and even that changes over time.
basic PSMF (as low/no carb as you can get)typically still has 10-30g of tag along carbs in it depending on food choices.
many low carb strategies use less then 20-25% of cal intake or 50-80g depending on bodywgt, cal level, tolerance etc.
for some (perhaps yourself) with little to no exper. with low carb. it can mean the 1g per lb of bw. or in that range. its all relative to where your coming from anyway.
from my past exper........i didnt have the success i was looking for in cutting until i limited carbs. at the time that meant down to 100-120g a day. over time i moved to UD 2.0 which had periods of @50g per day. i tried some PSMF for a bit but found that carb level a bit too low for me. of course by then 100g of carbs in (diet) day seemed like a binge.........its all relative.
anyway, thats my 2cents
good luck
bluejacket
New Member
nkl
good luck with your plan, ill be curious to see how it works out.
i do believe IF can help (to a degree) with better partitioning but its still not going to re-work ones ratio. when talking about gaining, if you have a propensity for gaining more fat then muscle (not just on hi carb diets) when bulking then using "smarter" methods ( IF, carb/cal control etc.) can help limit the fat gain (and muscle as well) but it wont eliminate it.
good luck with your plan, ill be curious to see how it works out.
i do believe IF can help (to a degree) with better partitioning but its still not going to re-work ones ratio. when talking about gaining, if you have a propensity for gaining more fat then muscle (not just on hi carb diets) when bulking then using "smarter" methods ( IF, carb/cal control etc.) can help limit the fat gain (and muscle as well) but it wont eliminate it.
DAN, look forward to the book. I've been very interested in fasting for a long time, ever since Ori's Warrior Diet articles came out on T-Nation.
With regards to muscle loss, even though 40 hours of fasting didn't show a huge shift toward atrogene expression, there still was a trend towards a catabolic state.
Also, research in fasting directly looking at amino acid flux from muscle shows release of amino acids after a relatively short period without food. As well as increases in Branched Chain Keto Acid Dehydrogenase complex activity increasing BCAA oxidation.
Since the BCAA's are the main aminos released during starvation and fasting, which are used directly or broken down to provide alanine and glutamine and glucose production, have you considered a low steady dose of BCAA supplementation during a fast.
Evidence in catabolic hospital patients (not directly applicable, but interesting to look at) as well as rodent research on fasting (again, not direct proof of anything) suggest BCAA's being beneficial to preserve muscle during catabolic states and specifically fasting.
And since oral administration of BCAA's doesnt require digestion, bypasses the liver and are like getting a BCAA infusion, it makes sense they would offset potential muscle loss during a fast.
With regards to muscle loss, even though 40 hours of fasting didn't show a huge shift toward atrogene expression, there still was a trend towards a catabolic state.
Also, research in fasting directly looking at amino acid flux from muscle shows release of amino acids after a relatively short period without food. As well as increases in Branched Chain Keto Acid Dehydrogenase complex activity increasing BCAA oxidation.
Since the BCAA's are the main aminos released during starvation and fasting, which are used directly or broken down to provide alanine and glutamine and glucose production, have you considered a low steady dose of BCAA supplementation during a fast.
Evidence in catabolic hospital patients (not directly applicable, but interesting to look at) as well as rodent research on fasting (again, not direct proof of anything) suggest BCAA's being beneficial to preserve muscle during catabolic states and specifically fasting.
And since oral administration of BCAA's doesnt require digestion, bypasses the liver and are like getting a BCAA infusion, it makes sense they would offset potential muscle loss during a fast.
The following studies are infusion studies with BCAA's, but since BCAA's are rapidly absorbed when ingested orally, it seems they would provide similar benefit in sparing muscle while fasting.
Nitrogen sparing induced early in starvation by infusion of branched-chain ketoacids.
* Sapir DG,
* Walser M.
The alpha-ketoanalogues of the branched-chain amino acids were administered to fasting subjects to determine whether or not they promoted nitrogen sparing. Two fasting studies were carried out in each subject. During the first week of one of the two fasts 4.7 g of a mixture of the alpha-ketoanalogues of valine, leucine, and isoleucine were infused daily. No infusions were administered during the other fast, which served as a control. Urinary urea and calculated total urinary nitrogen were significantly lower during both the week of infusions and the ensuing week of fasting after the infusions were discontinued. Immediately after ketoacid infusions, plasma branched-chain amino acids, including allosioleucine, rose, while alanine and several other amino acids (but not glutamine) fell. There were no differences between the two fasts with respect to ketone bodies, free fatty acids, glucose, insulin, or glucagon concentrations. We conclude that branched-chain ketoacids spare nitrogen early in fasting and that this effect persists after they are metabolized.
Infusion of the Branched Chain Amino Acids in Postoperative Patients: Anticatabolic Properties
Herbert Freund, Herbert C. Hoover, Jr., Susan Atamian, and Josef E. Fischer
Postinjury metabolism is characterized by breakdown of muscle protein as substrate for energy production and gluconeogenesis and by the resultant loss of lean body mass and weight loss. The branched chain amino acids (BCAAs) which are principally oxidized by the skeletal muscle have been implicated in recent in vitro and in vivo studies as having special anticatabolic and regulating effects in skeletal muscle. We studied the anticatabolic effects of the BCAAs in 35 patients undergoing operative injury of moderate severity. In a prospective randomized and blinded manner patients were infused for five days starting immediately after surgery with either 5% dextrose or 5% dextrose with an amino acid solution containing 22, 35 or 100% BCAAs. All patients survived and there were no major postoperative complications. Mean hospital stay was 17 days for patients receiving amino acids and 19 days for patients receiving 5% dextrose only (p = ns). All three groups receiving amino acid solutions were in nitrogen equilibrium or in a slight positive nitrogen balance, while the group receiving 5% dextrose only was in a mean negative nitrogen balance of 6.6 ± 0.6 gN/day. The differences between the three groups receiving amino acids were slight and not significant. Weight loss was 2 ± 0.7 kg in the 5% dextrose group, 1 ± 0.7 kg in the 22% BCAAs group, 0.5 ± 0.5 kg in the 35% BCAAs group and the 100% BCAAs group gained 0.4 ± 1.8 kg. Blood chemistries in the different groups and during the study period remained within normal limits except for ammonia levels rising significantly in the 5% dextrose group and SGOT levels rising in the 22% and 35% BCAA groups. With mild variations the plasma amino acid patterns in all groups were similar to the normal pattern, even in the 100% BCAAs group receiving an unbalanced amino acid solution, suggesting the complete cessation of amino acid efflux from muscle, the muscle depending solely on the exogenous supply of BCAAs to satisfy its metabolic requirements. The results suggest that early nutritional suppport in the postoperative period will result in nitrogen equilibrium and that the infusion of the three BCAAs only in the postoperative state is as effective in preventing muscle catabolism as other more balanced amino acid solutions. In the postinjury state balanced amino acid solutions rich in BCAA may prove beneficial.
Nitrogen sparing induced early in starvation by infusion of branched-chain ketoacids.
* Sapir DG,
* Walser M.
The alpha-ketoanalogues of the branched-chain amino acids were administered to fasting subjects to determine whether or not they promoted nitrogen sparing. Two fasting studies were carried out in each subject. During the first week of one of the two fasts 4.7 g of a mixture of the alpha-ketoanalogues of valine, leucine, and isoleucine were infused daily. No infusions were administered during the other fast, which served as a control. Urinary urea and calculated total urinary nitrogen were significantly lower during both the week of infusions and the ensuing week of fasting after the infusions were discontinued. Immediately after ketoacid infusions, plasma branched-chain amino acids, including allosioleucine, rose, while alanine and several other amino acids (but not glutamine) fell. There were no differences between the two fasts with respect to ketone bodies, free fatty acids, glucose, insulin, or glucagon concentrations. We conclude that branched-chain ketoacids spare nitrogen early in fasting and that this effect persists after they are metabolized.
Infusion of the Branched Chain Amino Acids in Postoperative Patients: Anticatabolic Properties
Herbert Freund, Herbert C. Hoover, Jr., Susan Atamian, and Josef E. Fischer
Postinjury metabolism is characterized by breakdown of muscle protein as substrate for energy production and gluconeogenesis and by the resultant loss of lean body mass and weight loss. The branched chain amino acids (BCAAs) which are principally oxidized by the skeletal muscle have been implicated in recent in vitro and in vivo studies as having special anticatabolic and regulating effects in skeletal muscle. We studied the anticatabolic effects of the BCAAs in 35 patients undergoing operative injury of moderate severity. In a prospective randomized and blinded manner patients were infused for five days starting immediately after surgery with either 5% dextrose or 5% dextrose with an amino acid solution containing 22, 35 or 100% BCAAs. All patients survived and there were no major postoperative complications. Mean hospital stay was 17 days for patients receiving amino acids and 19 days for patients receiving 5% dextrose only (p = ns). All three groups receiving amino acid solutions were in nitrogen equilibrium or in a slight positive nitrogen balance, while the group receiving 5% dextrose only was in a mean negative nitrogen balance of 6.6 ± 0.6 gN/day. The differences between the three groups receiving amino acids were slight and not significant. Weight loss was 2 ± 0.7 kg in the 5% dextrose group, 1 ± 0.7 kg in the 22% BCAAs group, 0.5 ± 0.5 kg in the 35% BCAAs group and the 100% BCAAs group gained 0.4 ± 1.8 kg. Blood chemistries in the different groups and during the study period remained within normal limits except for ammonia levels rising significantly in the 5% dextrose group and SGOT levels rising in the 22% and 35% BCAA groups. With mild variations the plasma amino acid patterns in all groups were similar to the normal pattern, even in the 100% BCAAs group receiving an unbalanced amino acid solution, suggesting the complete cessation of amino acid efflux from muscle, the muscle depending solely on the exogenous supply of BCAAs to satisfy its metabolic requirements. The results suggest that early nutritional suppport in the postoperative period will result in nitrogen equilibrium and that the infusion of the three BCAAs only in the postoperative state is as effective in preventing muscle catabolism as other more balanced amino acid solutions. In the postinjury state balanced amino acid solutions rich in BCAA may prove beneficial.
I'm going to briefly touch on some points and only briefly.
There is no denying that periods of brief fasting impact proteolysis but the overall impact is not nearly as great as most believe or what occurs during prolonged starvation.
For instance during human fasting lasting 60 hours the contribution to REE from protein oxidation only increased some 6%. While fat oxidation's contribution increased some 30% and the energy mobilized from fat stores rose from 192 kj/hr to 447 kJ/hr. Proteolysis increased from about 2.5 to 3.7 mg/kg/min. At the same time whole body PS increased nearly 40%, indicating that much of the product of the proteolysis was actually conserved and resynthesized.
I believe what also must be looked at is the changes seen in some hormones.
Insulin (pmol/L) from 53 to 26
Glucagon (ng/L) 159 to 299
Epinephrine (pmol/L) 143 to 296
Norepinephrine (pmol/L) 601 to 1219
Growth hormone (&#305;g/L) 1.9 to 11
Cortisol (nmol/L) 339 to 412
This study was done on lean healthy mean with an avg BF% of 22% indicating that even in normal healthy subjects the impact of a brief fast on skeletal muscle proteins isn't going to cause a huge degradation of one's hard earned muscle. This also doesn't take into account the effect of weight training while fasting which may even better partition the energy used away from skeleltal muscle or at the least heighten the muscle fractions of synthesis.
There is no denying that periods of brief fasting impact proteolysis but the overall impact is not nearly as great as most believe or what occurs during prolonged starvation.
For instance during human fasting lasting 60 hours the contribution to REE from protein oxidation only increased some 6%. While fat oxidation's contribution increased some 30% and the energy mobilized from fat stores rose from 192 kj/hr to 447 kJ/hr. Proteolysis increased from about 2.5 to 3.7 mg/kg/min. At the same time whole body PS increased nearly 40%, indicating that much of the product of the proteolysis was actually conserved and resynthesized.
I believe what also must be looked at is the changes seen in some hormones.
Insulin (pmol/L) from 53 to 26
Glucagon (ng/L) 159 to 299
Epinephrine (pmol/L) 143 to 296
Norepinephrine (pmol/L) 601 to 1219
Growth hormone (&#305;g/L) 1.9 to 11
Cortisol (nmol/L) 339 to 412
This study was done on lean healthy mean with an avg BF% of 22% indicating that even in normal healthy subjects the impact of a brief fast on skeletal muscle proteins isn't going to cause a huge degradation of one's hard earned muscle. This also doesn't take into account the effect of weight training while fasting which may even better partition the energy used away from skeleltal muscle or at the least heighten the muscle fractions of synthesis.
Interesting.
In regards to pete69's post on supplementing BCAAs, is there any data on how much the insulin rises when supplementing protein during fasting?
Another relevant question is how big the impact is on GH secretion by Ghrelin if you eat of protein and fat, but not carbohydrates (simulating fasting)? Does it require absence of food to trigger ghrelin?
In regards to pete69's post on supplementing BCAAs, is there any data on how much the insulin rises when supplementing protein during fasting?
Another relevant question is how big the impact is on GH secretion by Ghrelin if you eat of protein and fat, but not carbohydrates (simulating fasting)? Does it require absence of food to trigger ghrelin?
Eating protein will give a rise in both insulin and glucagon, scroll down to the chart on this link to see the insulin index of foods like beef, fish and eggs
http://www.mendosa.com/insulin_index.htm
As you can see, protein will cause a rise in insulin, and fish will cause the pancreas to release amounts similar to many carb-based foods.
From the research i've seen, most studies show no change in insulin, blood sugar or triglycerides with bcaa's, although i'd suspect if given in large doses this would change, as we know leucine is insulinogenic.
Off the top of my head, ghrelin is a gut hormone directly related to food in the gut, so I'd suspect that ghrelin does absolutely require no food.
Fasting raises growth hormone, which has been shown to be muscle sparing and if the rise in growth hormone is attenuated via a drug, muscle loss is increased.
But raising growth hormone nutritionally via supplements or dietary changes or exercise seems to do nothing for building muscle, contrary to what Kraemer and Fleck have been trying to show for years. Several studies from a Japanese research group showed giving GH along with lifting did nothing to enhance hypertrophy in older men.
http://www.mendosa.com/insulin_index.htm
As you can see, protein will cause a rise in insulin, and fish will cause the pancreas to release amounts similar to many carb-based foods.
From the research i've seen, most studies show no change in insulin, blood sugar or triglycerides with bcaa's, although i'd suspect if given in large doses this would change, as we know leucine is insulinogenic.
Off the top of my head, ghrelin is a gut hormone directly related to food in the gut, so I'd suspect that ghrelin does absolutely require no food.
Fasting raises growth hormone, which has been shown to be muscle sparing and if the rise in growth hormone is attenuated via a drug, muscle loss is increased.
But raising growth hormone nutritionally via supplements or dietary changes or exercise seems to do nothing for building muscle, contrary to what Kraemer and Fleck have been trying to show for years. Several studies from a Japanese research group showed giving GH along with lifting did nothing to enhance hypertrophy in older men.
Interestingly Millward looked at proteolysis many many years ago and specifically what occured at the muscle level in rats. What was noted in these fantastic studies was that it took nearly 4 days of total starvation to see a depression in PS and increase in PD enough to cause a negative protein balance. Even at 2 days of total starvation net balance was 0, but not negative. When compared to 30 days of protein free but sufficient caloric content feeding the PB in these rats were similar to the 4 days starved, indicating that even eating maintenance cals but free of protein will impact skeletal muscle net balance.
Secondly and even though Owen et al looked at obese subjects there are several interesting notes to be made about that work and some correspnding work done more recently. Namely that aminogenic compounds used for fuel dropped some 50% within day one of the fast then continued to decline throught the remainder of the fast. Secondly and rather importantly two other items occurred, 1. RMR actually increased on day 1 through 3 before dropping again to below basal RMR. This is probably because of the increase in the catecholamine-stimulated b-adrenergic activity (see the Norepinephrine response above and also in Zauner et al 2000). And 2. Like the information posted above fat oxidation increased dramatically almost 80% begining in day 1.
<div></div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE">From the research i've seen, most studies show no change in insulin, blood sugar or triglycerides with bcaa's, although i'd suspect if given in large doses this would change, as we know leucine is insulinogenic.</div>I would agree
Don't get me started on Fleck and Kraemer and their insistant search for how important GH is for hypertrophy
Secondly and even though Owen et al looked at obese subjects there are several interesting notes to be made about that work and some correspnding work done more recently. Namely that aminogenic compounds used for fuel dropped some 50% within day one of the fast then continued to decline throught the remainder of the fast. Secondly and rather importantly two other items occurred, 1. RMR actually increased on day 1 through 3 before dropping again to below basal RMR. This is probably because of the increase in the catecholamine-stimulated b-adrenergic activity (see the Norepinephrine response above and also in Zauner et al 2000). And 2. Like the information posted above fat oxidation increased dramatically almost 80% begining in day 1.
<div></div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE">From the research i've seen, most studies show no change in insulin, blood sugar or triglycerides with bcaa's, although i'd suspect if given in large doses this would change, as we know leucine is insulinogenic.</div>I would agree
Don't get me started on Fleck and Kraemer and their insistant search for how important GH is for hypertrophy
Thanks for the info, folks! I have two additional questions brewing...
1) Bluejacket, you mentioned using a weekly caloric deficit when doing IF. Shouldn't fat loss be possible also eating at maintenance or above, due to fat loss during fast?
My rationale is that the protein sparing effect keeps the LBM the same during IF. Then eating in abundance after workouts would lead to gains in both fat and LBM. As long as we can balance the loss-gain ratio we can adjust for more fat loss, or more LBM gain over time.
2) There seems to be a concensus on the Internet that the energy content in one pound of fat is 3500 kcal, and 600 kcal/lb for muscle, which would make packing on more LBM an easy task, while loosing fat a nuisance, at least in theory. Of course this is not the whole truth. But to make it somewhat useful, I'm curious as to what the rate-limiting pace for adding LBM is? Do we have an 'scientific' estimate on what growth rate we can expect on a weekly basis, for example doing regular 3-days-a-week HST (the norm - not on the juice - not a teenager or elderly)?
1) Bluejacket, you mentioned using a weekly caloric deficit when doing IF. Shouldn't fat loss be possible also eating at maintenance or above, due to fat loss during fast?
My rationale is that the protein sparing effect keeps the LBM the same during IF. Then eating in abundance after workouts would lead to gains in both fat and LBM. As long as we can balance the loss-gain ratio we can adjust for more fat loss, or more LBM gain over time.
2) There seems to be a concensus on the Internet that the energy content in one pound of fat is 3500 kcal, and 600 kcal/lb for muscle, which would make packing on more LBM an easy task, while loosing fat a nuisance, at least in theory. Of course this is not the whole truth. But to make it somewhat useful, I'm curious as to what the rate-limiting pace for adding LBM is? Do we have an 'scientific' estimate on what growth rate we can expect on a weekly basis, for example doing regular 3-days-a-week HST (the norm - not on the juice - not a teenager or elderly)?