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  1. #1
    KAEW44's Avatar
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    Growth hormone effect on natural GH levels???

    I'm not too familiar with growth hormone , but is it like T3 in the fact that using it over a period of time will supress or shut off your own body production? I know the body only produces a small amount of GH anyway in grown adults.....lets have some feedback please

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    bump, good question

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    To some degree yes! But GH timing is important when cycling, Taking GH early in the day might not interupt your nocturnal release, which is released during rem sleep at night.

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    Quote Originally Posted by Mallet
    To some degree yes! But GH timing is important when cycling, Taking GH early in the day might not interupt your nocturnal release, which is released during rem sleep at night.
    but do you think long term it could hamper your natural GH levels so
    they'll never be what they were our could be...........

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    Also, unpublished studies have suggested that repeated administration of GH before sleep may have effects on endogenous GH that extend beyond a GH cycle.....this too was in rats.

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    Here is a good debate!!! Maybe Einstein will clear it up for us.


    I'm currently in my 10th week of GH and wanted to add in slin for the last three weeks of my current 12th week cycle of Test, Fina, Winny and EQ, but cannot find the answer as timing of the insulin shot in conjuction with the GH.
    Currently I am taking 2 iu's in the morning and 2iu's at bedtime of GH and have started taking insulin (Humalog) at 2iu's (working my way up to 10iu's increasing 2iu's each day) should I change my second GH shot to post workout along with my insulin shot or should I keep the GH shots the way they are?
    I did a search (for about two hours now) but came up with to many conflicting theroies that shy-ed away from anyone answering the question-HELP!!!



    03-20-2003 08:02 AM User is offline




    ironmaster

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    Just in general, exogenous GH supresses insulin sensitivity. That is the reason that serious people use insulin in conjunction with GH injections. Since the half-lifes are similar, it makes good sense to use the humalog at the same time as the GH injection. It is my opinion that one should avoid bedtime for GH injections anyway since the exoGH will supress the natural surge in GH production that we experience during the first 2 hours of deep sleep.
    There....a direct answer from an old guy who has used GH and insulin for many years.



    03-20-2003 08:10 AM User is offline




    bigtest69

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    BUMP!
    This is a very good question. I have also heard conflicting ideas about timing insulin and gh shots. Some say the Insulin cancels the gh out if taken while the two are both active. I have also heard the oposite. Anyone care to clear this up?
    Thanks



    03-20-2003 01:54 PM User is offline




    T-Biggs

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    The reason behind the bedtime injections theory was brought up by Supergirl awhile back-which makes sense in stating that since exoGH will supress the natural surge in GH production (taking GH in the morning afternoon, bedtime etc....) then the night time natural surge would also be supressed (I believe its 1-1.5iu's) and since GH is at its most useful time at night the bedtime injection seems critical.
    However after continuing threads on various boards on the subject it seems the night time injections are more benifical to someone who's natural GH is gradually down-grading with age-over 30. I have seen the GH level charts posted around (Ironmaster I believe you posted one on Elite) and since my natural GH production has not begun to down-grade as of yet (I'm 27) afternoon injections would seem benifical. I have been injecting at bedtime for about 11 weeks now so in conclusion I think I will now try afternoon injections along with my insulin shots to see which works best for me.


    Last edited by T-Biggs on 03-20-2003 at 06:29 PM

    03-20-2003 06:22 PM User is offline




    T-Biggs

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    And thanks Ironmaster for clearing up the insulin/Gh shot!!!

    Anyone else have any other possible theories?



    03-20-2003 06:31 PM User is offline




    RoadHouse

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    I would definitley listen to ironmaster. I would do a morning GH/slin injectiopn before breakfast, and then a GH/slin injection post workout.


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    03-20-2003 10:51 PM User is offline




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    (Quote
    Originally posted by ironmaster
    Just in general, exogenous GH supresses insulin sensitivity. That is the reason that serious people use insulin in conjunction with GH injections. Since the half-lifes are similar, it makes good sense to use the humalog at the same time as the GH injection. It is my opinion that one should avoid bedtime for GH injections anyway since the exoGH will supress the natural surge in GH production that we experience during the first 2 hours of deep sleep.
    There....a direct answer from an old guy who has used GH and insulin for many years.


    hey dad

    gonna start a debate here with ya.. and don't hold back cause you love me ok

    alright... lets take that statement.. "exoGH will supress the natural surge in GH production that we experience during the first 2 hours of deep sleep"
    now, with that in mind.. wouldn't it be beneficial to substitute exog gh when your body would naturally produce it?? Meaning that since your natural surge at bedtime is suppressed, replacing the natural cycle would be beneficial...

    The research i have done all says to do shots at night... NOW this is also for someone NOT using insulin.. so perhaps with the addition of slin it would change beneficial shot times...

    NOW.. speaking from experience, my first gh cycle was afternoon shots post workout.. not much joint pain, not much results..
    2nd cycle was bedtime shots.. joints were sore for a month, sleep was great, recovery was better, and then joints healed.. SO IME, gh at bedtime really worked for me...
    Bedtime shots are also suggested for Serono users...


    so that is still my opinion based on personal experience and research... but i am totally up for a debate on this lol...

    so comeon dad.. Bring it!!! hahhahaha... and BTW.. i am sooooo glad you finally came here!!! LUV YOU!!!


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    03-21-2003 07:45 AM User is offline




    ironmaster

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    I knew my daughter, supergirl, would jump on this one. I phrased my reply so as to elicit your response, dear.

    First of all, you make good points. Using insulin pretty much requires that one inject other than at bedtime....wouldn't want to go hypo in our sleep, now would we? Also, I respect everyones opinion when they state it from PERSONAL experience. If it works well for you that way, great. You have a lot of experience, and are dialed in to your own body. And yes, I slept great when I tried night-time injects......vivid dreams!!!......you were in some of them....

    However, in general terms, I must disagree. Most of the research that recommends bedtime injections is aimed at the individual with a non-functioning pituitary. Children with severe growth disorders and those adults who have lost pituitary function from illness, radiation treatments, AIDS, or accidents should dose GH at bedtime so as to mimmick the natural rythyms of the healthy human endocrine system.
    But those who are HRT patients and bodybuilders should not. Why? Because we retain normal GH secretions, although perhaps somewhat diminished in the older lifter. ExoGH only makes the pituitary a little "lazy" for a few hours.....it is not shut down like in testosterone supplementation. Since we produce up to 80% of our natural GH during the first 2 hours of deep sleep, why not take advantage of that and dose our exoGH at a flat time like late afternoon?
    Even Genentech makes this distinction now in the instructions to physicians. They specify non-bedtime injections for HRT, bedtime for sick people. Genentech invented synthetic somatropin and holds the first FDA approval for medical use.
    OK, your turn.

    Love you too.....pop.

    This is a **** nice board....thanks for inviting me....you too, juice and max.



    03-21-2003 09:19 AM User is offline




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    hehehe.. i love debating with you... mainly because it is educational and never gets nasty!!!

    ok.. i see your point.. however it was my understanding and former research that once exogenous gh is administered, endogenous gh production is completely suppressed for a good 72hours.. very similar to testosterone suppresssion from exog test... (i know contradictory to what you stated)... now with that in mind, the idea of replacing natural gh peaks (bedtime) would seem appropriate.. as long as natural production is indeed suppressed...

    the question at hand is actual suppression!!! how long and how much!!! if it is in fact is only slowed as you state, then i agree with you 100% that the natural sleep peak should be taken advantage of!!
    and shots should then be administered at lulls... IF and only IF endogenous is only slowed and not suppressed... i need research papa

    bedtime shots for me do result in vivid dreams (i am so flattered i am in yours ) however theraputically as you said it works WONDERS!!! healing and recovery are accelerated...

    Now if one were desiring growth from GHRT, the best time would be afternoon with slin???

    i will try to find the articles on suppression...

    Glad you are here


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    03-21-2003 09:49 AM User is offline




    ironmaster

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    Ok, I'll throw some science at you if you insist. Here's one abstract (I have more):

    Lanzi R, Tannenbaum GS. Journal of Endocrinology

    Department of Pediatrics, McGill University, Montreal, Quebec, Canada.

    Endogenous pulsatile GH secretion is blunted by the administration of exogenous GH; however, few data are available on the time course of GH negative feedback, and the mechanism by which this occurs still remains unclear. In the present study, we examined the temporal pattern of the inhibitory effect induced by an acute (single) and chronic (5 days) sc recombinant human (rh) GH injection regimen on spontaneous GH release in the rat and assessed the possible involvement of the hypothalamic GH-inhibitory peptide, somatostatin (SRIF), in this response. Eight-hour (0800-1600 h) GH secretory profiles, obtained from free-moving adult male rats administered a single sc injection of 200 micrograms rhGH at 0800 h, revealed a marked suppression of spontaneous GH pulses (GH peak amplitude: 45.7 +/- 10.9 vs. 207.8 +/- 31.7 ng/ml in H2O-injected control rats; P less than 0.001) lasting for up to 4.1 +/- 0.1 h after the injection (mean 4-h plasma GH level: 13.6 +/- 3.6 vs. 49.4 +/- 7.0 ng/ml in H2O-injected controls; P less than 0.01). During the subsequent 4- to 8-h period, recovery of spontaneous GH secretory bursts was evident, and neither the GH peak amplitude nor mean 4-h plasma GH level of rhGH-treated rats was significantly different from that of H2O-injected controls. The magnitude, time course, and recovery of the rhGH-induced inhibitory effect on pulsatile GH release after chronic rhGH treatment was similar to that after a single injection. Passive immunization of rhGH-treated rats with SRIF antiserum reversed the rhGH-induced inhibition of spontaneous GH pulses (peak amplitude: 131.7 +/- 53.7 vs. 7.1 +/- 3.4 ng/ml in rhGH-treated control rats given normal sheep serum; P less than 0.05) and restored both the GH peak amplitude and mean plasma GH level to values similar to those in H2O-injected controls. Taken together, these results demonstrate that: 1) the inhibitory effect of rhGH on endogenous pulsatile GH release is of short duration (approximately 4 h); 2) the time course of this response does not change after 5-day repeated rhGH administration; and 3) the feedback effect of GH on its own spontaneous release is exerted, at least in part, by increasing hypothalamic SRIF secretion. Such a mechanism of GH feedback may be important in the physiological control of pulsatile GH secretion.

    Hey, SG, do you have any new pics? How's the training coming along? (Naked pics would be fine if you don't have any training photos....)



    03-22-2003 07:45 AM User is offline




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    THANK YOU IM...

    and i will just ignore that last statement LOL... training pics by May


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    03-23-2003 03:57 AM User is offline




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    ok.. time to throw a monkey in the wrench.. here is an article found (courtesy of Nandi)...
    http://jcem.endojournals.org/cgi/co...ll/85/2/601#R31

    "The reduction of serum 22K-hGH level after 20K-hGH administration required a period of ca. 4 h, and the level tended to recover by 24 h. However, the delay in suppression of endogenous 22K-hGH by exogenous 20K-hGH is difficult to define precisely because of the intermittent nature of hGH secretion"


    basically once exogenous gh is administered, endogenous is suppressed for about 24hours.. Plus we forgot to take into consideration that IGF-1 also suppresses natural gh, so now we have (2) components working together to suppress endogenous... which therefore will keep natural gh suppressed for ~24hours...

    so.. bedtime shots which is what i have testified to all along seem to be the best to do... you shoot your gh, go to sleep, get your natural peak, then the exogenous gh kicks in (takes ~4 hrs to kick in) and then gh is active for quite some time... so this way you get almost double the dosage Natural and exog in one night!!!

    The great thing about this study is that it is finally on HUMANS and not rats!!!

    so now whatcha think dad???


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    03-28-2003 08:20 AM User is offline




    SWALE

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    A simple question: why substitute GH that you have to buy, for GH that your body will just give you?


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    03-29-2003 03:09 AM User is offline




    T-Biggs

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    To answer your question SWALE your body produces .5 to 1.5 iu's of GH per day so an increase over that can provide increased benifits.


    And Thanks Ironmaster/Supergirl for you responses/great info (keep them coming)-which has been extremely helpful to me and I am sure others on the board!!



    03-29-2003 05:26 AM User is offline




    SWALE

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    You didn't quite get my question.


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    RoadHouse

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    (Quote
    Originally posted by SWALE
    A simple question: why substitute GH that you have to buy, for GH that your body will just give you?

    For that matter, why subsitute Testerone you have to buy, for testerone that your body gives you?


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    03-29-2003 06:37 AM User is offline




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    To a certain extent not to extremes, more is better.


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    03-29-2003 06:38 AM User is offline




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    (Quote
    Originally posted by SWALE
    A simple question: why substitute GH that you have to buy, for GH that your body will just give you?


    Well also as you get older, your gh production dramatically decreases... so the idea is HRT to get levels back up where they were in puberty... hence causing hypertrophy and all the wonders of gh...


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    03-29-2003 07:37 AM User is offline




    SWALE

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    My point was that if you take your GH at night, you suppress your own GH production. You are therefore paying (a lot of money) for something your body will give you for free. If you take it in the AM, the effect is diminished. Of course, if you are taking enough to completely suppress your own system, the point is probably moot.


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    03-29-2003 03:15 PM User is offline




    ironmaster

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    Correct, Swale.

    SG, honey, that isn't what the study you cited says. I know that one. It basically says it's hard to give an answer, but after 4 hours, recovery is underway.......and ALL suppression, no matter to what lesser degree, is undetectible after 24. I have many reports on this topic....I'll post some tomorrow, including human studies. The companes that specialize in HRT types of GH (not the people who have totally non-function pituitaies)recommend morning or late afternoon.
    I need to mail Nandi.....I want to check his research on IGF levels as a test for doping in elite athletes.



    03-30-2003 10:01 AM User is offline




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    Actually, the study says that "the reduction of serum 22K-hGH level after 20K-hGH administration required a period of ca. 4 h, and the level tended to recover by 24 h"

    ..which can be seen from the graph:

    Figure 2. Mean serum 20K-hGH (A) and 22K-hGH (B) levels in normal men after single sc administration of placebo and 20K-hGH. Sera were analyzed by 20K-hGH and 22K-hGH ELISA, respectively. The values are means ± SE (n = 6–8). Placebo and 20K-hGH (0.01–0.1 mg/kg) were administered at 2100 h. In the placebo group, the typical nyctohemeral variations in hGH secretion were observed.


    hhajdo has attached this image:



    03-30-2003 08:39 PM User is offline




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    Morning injection might cause less suppression, but GH response to GHRH is significantly reduced for more than 12 hours...


    Clin Endocrinol (Oxf) 1987 Jan;26(1):117-23 Related Articles, Links

    Growth hormone pretreatment in man blocks the response to growth hormone-releasing hormone; evidence for a direct effect of growth hormone.

    Ross RJ, Borges F, Grossman A, Smith R, Ngahfoong L, Rees LH, Savage MO, Besser GM.

    The effect of pretreatment with biosynthetic methionyl human GH (hGH) on the GH response to GHRH has been studied in normal subjects. Eight volunteers were given either 4 IU hGH or placebo s.c. 12-hourly for 72 h before a GHRH test, or a single s.c. dose of 4 IU hGH 12 h before a GHRH test. Somatomedin-C (Sm-C) levels at the time of the GHRH tests were significantly elevated after treatment with hGH compared to placebo, and the GH response to GHRH was significantly attenuated. A further six subjects were given 2 IU hGH or placebo i.v., and i.v. GHRH 3 h later; there was no rise in Sm-C for the 5 h of the study after either treatment; nevertheless, the response to GHRH was completely abolished by pretreatment with hGH. These results demonstrate that GH can regulate its own secretion independently of changes in Sm-C levels, through a mechanism other than the inhibition of GHRH release. The attenuated response to GHRH in the presence of elevated Sm-C levels may be related to Sm-C, or be a more direct effect of the recently elevated GH levels.



    03-30-2003 08:41 PM User is offline




    hhajdo

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    Suppression of the growth hormone (GH) response to clonidine and GH-releasing hormone by exogenous GH.

    Nakamoto JM, Gertner JM, Press CM, Hintz RL, Rosenfeld RG, Genel M.

    GH release in response to clonidine and human GH-releasing hormone-(1-44) (hGHRH-44) was assessed in 11 boys (aged 7-14 yr) with short stature, who had normal GH secretion. The response to these 2 provocative stimuli was repeated after, respectively, 2 and 3 days of treatment with human GH (0.1 U/kg, im). Exogenous GH significantly blunted the response to both clonidine [the mean 2-h integrated serum GH concentration falling from 1050 +/- 350 (+/- SEM) to 749 +/- 297 ng/ml X min; P = 0.03] and hGHRH-44, the 2-h integrated GH concentration falling from 1553 +/- 358 to 547 +/- 202 ng/ml X min; (P = 0.03). Plasma insulin-like growth factor (IGF-II) concentrations did not change after GH administration. In contrast, plasma IGF-I (somatomedin-C) concentrations increased from 97 +/- 16 ng/ml before administration of GH to 142 +/- 32 ng/ml (P = 0.05) after two days and 149 +/- 23 ng/ml (P less than 0.01) after the third treatment day. However, no correlation was found between the changes in response to clonidine or hGHRH-44 and changes in circulating levels of IGF-I. Our data confirm the existence of GH-dependent feedback inhibition of GH release during childhood and suggest that this inhibition operates, at least in part, at the level of the pituitary. While participation of the IGFs/somatomedins in this feedback loop cannot be excluded, the inhibitory effects of exogenous GH do not depend directly on circulating plasma IGF-I or IGF-II levels.



    03-30-2003 08:43 PM User is offline




    hhajdo

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    J Clin Invest 1986 Jan;77(1):176-80 Related Articles, Links


    Exogenous growth hormone inhibits growth hormone-releasing factor-induced growth hormone secretion in normal men.

    Rosenthal SM, Hulse JA, Kaplan SL, Grumbach MM.

    Previous studies from this laboratory and by others in rats, monkeys, and humans support the concept that growth hormone (GH) can regulate its own secretion through an autofeedback mechanism. With the availability of human growth hormone-releasing factor (GRF), the possible existence of such a mechanism was reexplored by examining the effect of exogenous GH on the GH response induced by GRF-44-NH2 in six normal men (mean age, 32.4 yr). In all subjects the plasma GH response evoked by GRF-44-NH2 (1 microgram/kg i.v. bolus) was studied before and after 5 d of placebo (1 ml normal saline i.m. every 12 h), and then before and 12 h after 5 d of biosynthetic methionyl human GH (5 U i.m. every 12 h). The GH response to GRF (maximal increment over time 0 value) was significantly inhibited after GH treatment (0-1.3 vs. 2.3-11.2 ng/ml before treatment, P = 0.05), but was not significantly affected by placebo. This impaired pituitary response to GRF persisted for at least 24 h following exogenous GH treatment in two subjects who underwent further study. Serum somatomedin-C concentrations were significantly increased after 5 d of GH treatment (2.66-5.00 vs. 0.92-1.91 U/ml before treatment, P = less than 0.01). The impaired pituitary response to GRF may be mediated indirectly through somatomedin, somatostatin, by a direct effect of GH on the pituitary somatotropes, or by all of these mechanisms. These data suggest that after GH treatment, the blunted GH response to synthetic GRF is not solely a consequence of the inhibition of hypothalamic GRF secretion.




    I would still expect that morning injection wouldn't have as much impact on sleep-related growth hormone secretion....




    Last edited by hhajdo on 03-30-2003 at 08:48 PM

    03-30-2003 08:44 PM User is offline




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  7. #7
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    I've read that depabte many times over, and it all relies on the two ancient studies that show the lag in effects of exo GH. The much more recent studies in rats show a more reasonable view of things, based on GH's half-life. There have been nothing to substantiate those old GH studies that people keep alluding to. The rat studies, which people just seem to shrug off, are very current and show exo GH suppressing endo GH for 4-8hrs, with the peak of suppression at about 4-5hrs post injection. This is all going to be dose-dependent too, as a higher dose will induce more IGF-1, which will allow for a longer duration of GH suppression.

    I've read that thread at S'ology several times as well as the more current one that someone started over there. Until there are further tests to substantiate one or the other, I'm still going to go on what's most logical, based on all the things we DO know....namely, GH's short half-life and, although there certainly will be a lag during the time that IGF-1 levels mount in response to GH, it's not realistic to assume this will be a 18 or so hr lag. We know fairly well the natural pulsatile fashion of endo GH release and its timing....that alone should raise a red flag, when we see the old GH studies that show a dramatically different timing with exo GH.

  8. #8
    flexshack is offline Member
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    bloob
    Last edited by flexshack; 01-19-2012 at 10:36 PM.

  9. #9
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    Quote Originally Posted by flexshack
    how far beyond the cycle? were there permanent changes?

    couldn't lr3 have the same effect?
    I shouldn't have even posted that, since there isn't anything published to support this. I've heard, weeks, months....long-term. I don't understand why this would occur, so take it with a grain of salt until it gets published (if ever so).

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