Title: Mechanical load increases muscle IGF-I and androgen receptor mRNA concentrations in humans.

Researchers: Bamman MM, Shipp JR, Jiang J, Gower BA, Hunter GR, Goodman A, McLafferty CL Jr, Urban RJ.

Institution: Department of Surgery, University of Texas Medical Branch, and 2 Metabolism Unit, Shriners Hospitals for Children, Galveston, Texas 77550 Source: American Journal of Physiology Endocrinology & Metabolism. 2001 Mar;280(3):E383-90.

Summary: These investigators looked at the effects of concentric (CON) reps vs. eccentric (ECC) reps on muscle insulin-like growth factor-1 (IGF-I) mRNA concentration. They hypothesized a greater IGF-I response after ECC compared with CON.

Methods: Ten healthy subjects (Average age 24.4 yrs) completed eight sets of eight CON or ECC squats separated by 6-10 days. IGF-I, IGF binding protein-4 (IGFBP-4), and androgen receptor (AR) mRNA concentrations were determined in vastus lateralis from muscle biopsy before and 48 h after ECC and CON. Serum total testosterone (TT) and IGF-I were measured serially across 48 h, and serum creatine kinase activity (CK), isometric maximum voluntary contraction (MVC), and soreness were determined at 48 h.

Results: IGF-I mRNA concentration increased 62% and IGFBP-4 mRNA concentration decreased 57% after ECC. The direction of these changes after CON were similar but not statistically significant. AR mRNA concentration increased after ECC (63%) and CON (102%). Serum levels of total testosterone and IGF-I showed little change. MVC fell 10% and CK rose 183% after ECC squats. Perceived soreness was higher after ECC compared with CON.

Conclusion: Results indicate that a single bout of mechanical loading in humans alters activity of the muscle IGF-I system, and the enhanced response to ECC suggests that IGF-I may somehow modulate tissue regeneration after mechanical damage.

Discussion: Nothing in this study should really surprise us. But it does shed light on how lifting weights selectively regulates anabolic activity to specific tissues of the body. Training increased both androgen receptors as well as muscle specific IGF-1.

Training causes an increase in androgen receptors (testosterone receptors) on muscle cells, which increases the sensitivity of your muscle to your natural testosterone levels. This effect of training on androgen receptors is specific to muscle tissue. In other words, you are not going to see an increase in the effects of testosterone in other tissues such as your hair or your skin. So unlike using steroids, training only increases the effects of testosterone in muscle tissue.

IGF-1 is another critical player in muscle growth. Muscle growth from weight training is the result of IGF-1 being produced by the muscle cells themselves, not the liver. In fact, IGF-1 from the liver is genetically different from IGF-1 produced in your muscles. This is the reason why using IGF-1 systemically (from the blood stream) has been a hit and miss proposition.

IGF-1 formation in muscle tissue is absolutely critical if significant muscle hypertrophy is to occur. IGF-1 produced inside muscle cells that have been damaged by heavy training, oozes out of the cell and activates satellite cells. These satellite cells then donate nuclei to the damaged muscle cell, thereby allowing it to grow larger than before. There is a limit to the size of a muscle cell, and it depends largely on the number of nuclei it has. If you prevent a muscle cell from getting more nuclei from satellite cells, it simply will not grow, no matter how heavy things get. (1,2,3) The reduction in IGF binding protein-4 (IGFBP-4) leads to increased IGF-1 activity.(4) [Note: IGFBP-"3" also binds IGF-1 but in a good way. IGFBP-3 is the main carrier of IGF-1 and prolongs the half-life of IGF-1]

I would like to voice my strongly held opinion that the ever so slight changes in systemic hormone levels as a result of exercise are not responsible for the muscle growth observed with resistance exercise. Instead, as this study illustrates, it is the changes that occur within the muscle cells themselves that account for any hormonal contributions to hypertrophy. Both an increase the muscle's sensitivity to existing androgen levels, increases in intracellular IGF-1 levels, with concomitant decreases in inhibitory IGF binding proteins are the primary "hormonal" mechanisms for muscle growth as a result of training (excluding the use of exogenous hormones).

1. Rosenblatt JD, Parry DJ., Gamma irradiation prevents compensatory hypertrophy of overloaded extensor digitorum longus muscle. J. Appl. Physiol. 73:2538-2543, 1992

2. Rosenblatt JD, Yong D, Parry DJ., Satellite cell activity is required for hypertrophy of overloaded adult rat muscle. Muscle Nerve 17:608-613, 1994

3. Phelan JN, Gonyea WJ. Effect of radiation on satellite cell activity and protein expression in overloaded mammalian skeletal muscle. Anat. Rec. 247:179-188, 1997

4. Schneider MR, Lahm H, Wu M, Hoeflich A, Wolf E. Transgenic mouse models for studying the functions of insulin-like growth factor-binding proteins. FASEB J 2000 Apr;14(5):629-40

Title: Performance and muscle fiber adaptations to creatine supplementation and heavy resistance training.

Researchers: Volek JS, Duncan ND, Mazzetti SA, Staron RS, Putukian M, Gomez AL, Pearson DR, Fink WJ, Kraemer WJ.

Institution: Department of Kinesiology/Center for Sports Medicine, The Pennsylvania State University, University Park 16802, USA. Source: Med Sci Sports Exerc 1999 Aug;31(8):1147-56 Related Articles, Books, LinkOut

Summary: The purpose of this study was to examine the effect of creatine supplementation in conjunction with resistance training on muscle fiber hypertrophy and muscle creatine accumulation.

Methods: Nineteen healthy resistance-trained men were matched and then randomly assigned in a double-blind fashion to either a creatine or placebo group. Periodized heavy resistance training was performed for 12 wk. Creatine or placebo capsules were consumed (25 g x d(-1)) for 1 wk followed by a maintenance dose (5 g x d(-1)) for the remainder of the training period.

Results: After 12 wk, significant increases in body mass and fat-free mass were greater in creatine (6.3% and 6.3%, respectively) than placebo (3.6% and 3.1%, respectively) subjects. After 12 wk, increases in bench press and squat were greater in creatine (24% and 32%, respectively) than placebo (16% and 24%, respectively) subjects. Compared with placebo subjects, creatine subjects demonstrated significantly greater increases in Type I (35% vs 11%), IIA (36% vs 15%), and IIAB (35% vs 6%) muscle fiber cross-sectional areas. Muscle total creatine concentrations were unchanged in placebo subjects. Muscle creatine was significantly elevated after 1 wk in creatine subjects (22%), and values remained significantly greater than placebo subjects after 12 wk. Average volume lifted in the bench press during training was significantly greater in creatine subjects during weeks 5-8. No negative side effects to the supplementation were reported.

Conclusion: Creatine supplementation enhanced fat-free mass, physical performance, and muscle morphology in response to heavy resistance training.

Discussion: Creatine is a naturally occurring compound made within our own bodies. It is also found in many foods we eat, especially meat. Creatine monohydrate has been used as a dietary supplement for at least a decade now, though it was first discovered nearly 170 years ago.

People seem to want to pigeonhole creatine into some sort of hit-or-miss water-retention supplement. Creatine is so much more than that. Creatine is truly one of the greatest supplements there is for building muscle and strength.

There was significant weight gain in this study. The creatine group "loaded" creatine the first 7 days. This was followed by 5 grams per day thereafter. One would expect a significantly greater weight gain the first week over placebo simply because of the well known effect of creatine loading on acute intracellular water retention (cell volumizing). But if this was the only way creatine lead to weight gain, this accelerated weight gain should have tapered off by the end of the first week, then stayed parallel to the placebo group through week 12. Instead, the acceleration of weight gain continued throughout the entire study period reaching nearly 10 pounds of lean mass by week 12! The placebo group gained only 4—in the same period. The creatine group literally doubled their muscle growth by using creatine. This means that creatine continued to effect lean mass gains long after its initial effect on water levels. This increase in body weight was then demonstrated to be true hypertrophy of muscle fibers.

In this study they were able to show, that in trained subjects, creatine supplementation increased muscle mass by nearly twice as much as placebo. Type I muscle fibers increased 35% with creatine but only 11% without it. Likewise, type IIA increased 36% compared to 15%. And finally, Type IIAB fibers increased 35% with creatine supplementation compared to only 6% without it. So on average, creatine supplementation produced 3 times the percentage of muscle fiber growth as placebo. You'd have to be a fool to ignore that!

There's no time to go into the many of other beneficial effects of creatine monohydrate. Suffice it to say, we will be taking a closer look at a lot of research on creatine in the issues to come. Stay tuned!

What is the Hypertrophy-Specific Street Team?
The Hypertrophy-Specific Street Team (HS:Street Team) is a way for me to give back to those who, out of the generosity of their hearts, have supported me by spreading the word about ThinkMuscle, HST, and now the HSN line of supplements.

Those who become members of the HS:Street Team, will receive any number of gifts and special values for their efforts to spread the word about HSN/HST.

How will the gifts and special values be given?
In order to give most to those who give most to HSN, many of the rewards and special values will be given out based on the number of referrals (and subsequent purchases) of HSN products that a Street Team member is responsible for. This will work by assigning each Street Team member a unique code (e.g. HS:ST member's email address), that they will then give to people to use when they make a purchase on the HSN website. This code will provide a discount for that person, as well as credit/points or cash for the Street Team member. The Street Team member will then be able to cash them in for HSN product (Getting the highest quality products for next to nothing ain't bad.), HS:Gear (shirts, bags, lifting straps, shaker bottles that don't leak, and whatever else we can come up with), or simply take the cash and run. They will also be the first to know about upcoming events, products, etc. from Hypertrophy-Specific Nutrition.

HS:Street Team members also have their own forum to share strategies about how to get as many referrals as they can with the least amount of effort. Ideas such as putting their unique code on flyers, bulletin boards in gyms, on their website, and any other methods of reaching a lot of people at a time.

Who is a candidate to become an HS:Street Teamer?
HS:Street Teamers are NOT to be simple sales people or anything of the sort. Street Teamers are people who, through their own efforts, have come to know and believe in what Hypertrophy-Specific Nutrition (and HST, and ThinkMuscle) stand for. Namely, HSN, HST, and ThinkMuscle stand for 1) the free exchange of accurate and unbiased information about training, nutrition, and supplementation, 2) the highest standards in quality when manufacturing supplements and training gear, and 3) absolute truth in advertising even if it means losing sales. Anyone who also believes in these standards, and wants to be a part of our efforts to spread these standards throughout the industry (magazines, supplement companies, gyms, etc), and wouldn't object to receiving something for their efforts, is a candidate for the HS:Street Team.

The HS:Street Team is now forming!

For those who are currently members of the HS:Street Team:
Get your self some cash and give your buddies an Instant Rebate when they come to The HS:Store and purchase the Primer/Driver System. Just have them type in your email address* in the "special Instructions" box at the bottom of the "payment details" page while ordering the Primer and Driver together, and they will get a $5.00 instant rebate and you will get $5.00 in CASH deposited directly into your PayPal account! Spend it anyway you want. Transfer it from your PayPal account into your bank account, or spend it in a myriad of other ways. It's up to you!

As many times as somebody orders with your email address in the special instructions box, you will get $5.00 instantly! It doesn't matter who it is, you don't even have to know them, they just have to put your email address in the special instructions box to receive the instant rebate, and you get the cash.

In order to protect you from losing your residual rewards, the rebate/cash offer does not apply to one's own purchases. So, when your referrals re-order their protein each month, they will input your [Street Team] email address again to receive their $5.00 rebate‹and you'll AGAIN get the $5.00 CASH!! The point is to motivate Street Team members to spread the word to as many people as possible.

Here's how you get started:
You must sign up for a FREE PayPal account for us to transfer cash and rebates to you. If you've already made a purchase from the HSN website, you're already a PayPal member.

If you are already a PayPal member, be sure that steps 2-4 have been completed on your account.

PAYPAL INSTRUCTIONS:

1) Go to: www.paypal.com and SIGN-UP for a FREE PayPal account.

2) Complete the EMAIL CONFIRMATION that will be sent to the address you signed up with.

3) Log in to your new account, and "Verify" your account (left side "Get Verified") by adding your Bank Account (Checking or Savings) to your PayPal profile. This is the bank account you would transfer funds TO and FROM your PayPal account.

4) Add a Credit Card (left side "Add a Credit Card") to your account. This is the card you use for online purchases. This will allow you the option of purchasing with EITHER your PayPal account funds, or a credit card.

Following these steps before making a purchase from the HSN Store will enable you (and those you refer to buy the supplements) to have an easy/quick buying experience.

Stay tuned for more cool stuff for HS:Street Teamers. . .

*The email address used for HS:Street Team benefits (cash back, rebates, etc) must be the same email address you used to sign up for the HS:Street Team AND PayPal. If your [Street Team] email address is not on your PayPal account, you'll need to add it.