Insulin & Somatotropin

[BJJ]

Insulin is often referred to as “the most anabolic hormone”. Unfortunately, this means it builds adipose tissue as well as muscle. Although it’s possible to get a nice “natural” anabolic effect by simply eating about 1g/kg of carbohydrate and some protein after a workout, endogenous (naturally-produced) insulin production is reduced during and immediately after exercise. This is mostly due to the effects of increased circulating catecholamines (epinephrine and norepinephrine). These “fight or flight” hormones put the damper on one’s pancreas. This is too bad for bodybuilders since GH may really be flowing at this time (depending on meal timing, age, etc.) and it seems to have very, very synergistic anabolic effects when present at the same time as insulin. In fact, there is research showing how GH or insulin alone have little effect on weight gain in animals, but when injected together (simultaneously), animals triple in size!! 1 It’s speculated that GH stimulates uptake of about half of the 9 or so essential amino acids into muscle, while insulin stimulates the uptake (or prevents the loss) of the complimentary half.1 Since all must be present for protein synthesis, vóila! Notice that I said “injected together” – this does not occur naturally. GH and insulin are largely counter-regulatory (and not present together), so their dramatic effects have been reserved for drug users.

For whatever reason, the dramatic findings of the injectable insulin/GH “stack” still lack empirical support in humans.2 But as many bodybuilders realize, researchers are often playing catch-up, trying to document the results that self-experimenting bodybuilders already experience. Thus, some athletes are taking advantage of any possible synergism by injecting about 10 international units (IU’s) of insulin immediately following a workout when GH is surging. (NOT advisable!) Such attempted manipulation of GH/insulin synergy is an effort to both dramatically enhance the anabolism of muscle tissue AND reduce the fat accumulation that insulin would cause if used alone. (Recall that GH is potently lipolytic.) It seems that post-workout timing is the key to this (dangerous) drug strategy.

And comments from national-caliber athletes suggest even more complex insulin/GH strategies. To further increase the effects of this powerful combination, a relatively mild aerobic or weight workout at least 4-5 hours apart from the “main” training session, is sometimes used to get another GH surge and thus a second chance during the day to use insulin when it’s most effective. A brief literature search reveals that this second workout of the day need only be about 10-20 minutes in duration and at a moderate intensity to elicit a GH surge that lasts 15-40 minutes after exercise.2 The game plan here, I believe, is to up the anabolic drive, not to lose existing fat per sé. I say this because such a “workout” probably wouldn’t do much from a (fat) calorie-burning point of view. It’s just not long enough. Using a beta-2 adrenergic agonist like clenbuterol or an ephedra/yohimbe blend would only serve to suppress GH release as well,2 so this “two-a-day” approach must be primarily for anabolic purposes. Although illegal and potentially lethal due to acute hypoglycemia, such a complex strategy does sound insidiously clever. The short and relatively mild second training session would hardly put a damper on even the “midgets of recuperative ability” as Mike Mentzer might say. As usual, I’m amazed by the ingenuity and resourcefulness of bodybuilders who are determined to get huge. I none-the-less do NOT condone or recommend the use of insulin to healthy athletes at any time of the day - nothing in bodybuilding can kill you faster if used improperly!

If about 100g carbohydrate is not consumed within about 30 minutes of a 10 IU insulin injection (e.g. Humulin-R), lethal hypoglycemia can result!

What can we learn from the complex and rather scary strategies that some drug-using athletes self-impose? Let’s look closely…

The first thing I notice is the timing issue. Eating a large amount of carbohydrate and protein (say, 50-100 grams of each) within the two-hours following a workout is likely to help (the sooner the better). Sure, I said insulin release will be blunted from exercise-released catecholamines, but if the amount and type of food is right, it’s a doable strategy. Insulin will be secreted in reasonable amounts and unless you’re insulin resistant, your muscles will readily benefit. In fact, they’ll benefit even without insulin due to the effects of exercise alone (e.g. increased GLUT-4 transporter and glycogen synthase activity). Plus, if you’re young enough and/or using an effective GH secretagogue (currently rare), you’ll also have GH maximized. The provision of carbohydrate and protein while muscles are “greedy” and GH is circulating seems a logical mechanism for the anabolic effects of a post-training meal. My belief is that nature has meticulously crafted us to replenish ourselves and recover immediately after exertion. This concept has clear survival value from an evolutionary perspective.

Another lesson that can be gleaned from drug-using athletes is that hormones work together. Simply boat loading GH does little without testosterone and/or insulin. The anabolism GH induces alone is largely organ mass.2 And insulin is not only acutely dangerous if used improperly, it’s also likely to induce some serious fat gain if used alone. Together, however, there is the potential for enhanced muscle recovery and growth without tremendous fat accumulation.

Lastly, performing a brief second workout is also a clever strategy seen among elite athletes. If we can induce a GH surge with minimal effort (perhaps before breakfast in the morning) we could garner the benefits of TWO post-workout “nutrient windows” in which to optimally use a big carb and protein meal. Two such replenishing windows could theoretically DOUBLE an athlete’s anabolic drive for the day. If the “mini” secondary workout is brief and of low intensity, it shouldn’t interfere much with recovery. Carefully selected supplements may further improve these recovery windows, augmenting one’s natural hormones and driving-in still more glucose and amino acids for growth.

References

1. Guyton, A.C. (1996). Medical Physiology W.B. Saunders Co., Philadelphia, PA.

2. Yareshesky, K.E. (1994). Growth hormone effects on metabolism, body composition, muscle mass, and strength. Exercise and Sport Science Reviews. 22: 285-312.

[Chev]

good read.