Link between IGF-1 and Nitric Oxide
And for my second post, I’d like to share an excerpt of a book called Get The Pump, written by Scott Abel and an array of professional bodybuilders.
This particular section talks about the relationship between IGF-1, Nitric Oxide (NO), the pump and how it all works in the protein synthesis and hypertrophy (growth) process.
Nitric Oxide (NO)
NO is a hormone that increases blood flow to the muscle cell and as a result, has pronounced effects on muscle growth. What’s more, the other two hormones we’ll soon learn about are dependent upon NO in order to exert their influence on blood flow and growth. NO is the linchpin that triggers the explosion.
The amount of NO your body makes is tightly controlled by an enzyme called nitric oxide synthase. When you train hard, the level of nitric oxide synthase increases three to six fold, which means more NO is made. When you start exercising, signals are sent to the nitric oxide synthase enzymes to make a lot more NO. NO is so important in producing a pump that some of the nitric oxide synthase enzymes are located within the muscle and some are in the blood vessels surrounding the muscles. This allows NO to work quickly o the muscles and the blood vessels to create a pump and influence growth.
NO is the primary factor in helping your body make and sustain a pump. In fact, NO not only sustains a muscle pump, but is also responsible for attaining maximal muscle pump, which allows NO to exert all its positive effects on muscle growth. That’s because NO has a direct influence on satellite cell activation and prompts them to fuse with muscle fibers, thus making your muscles bigger. And not only does NO boost muscle growth itself, but it also builds muscle by elevating other muscle building hormones such as VEGF and, just as importantly, IGF-1.
Insulin-Like Growth Factor-1 (IGF-1)
As I said earlier in this chapter, as you’re training, tiny holes are created when you tear the muscle fibers. This causes the muscle to produce IGF-1, and this IGF-1 leaks out and has a whole host of effects on growth.
IGF-1 influences muscle growth mainly by activating satellite cells and causing them to fuse into existing muscle fibers, as well as increasing the rate of protein synthesis. This is a sort of one-two punch, if you will. The fact that IGF-1 influences both satellite cell activation and muscle protein buildup suggests a link between IGF-1 and NO. They definitely seem to work in concert with one another in satellite cell activation, muscle repair, and growth when you’re pumped. Here’s some proof:
Research shows that IGF-1 is able to enhance muscle pumps by influencing and increasing NO. And research also shows that you need NO in order for IGF-1 to boost muscle growth. The codependency of NO and IGF-1 is very intriguing and , as yet, not totally understood. But what is understood is that both NO and IGF-1 create pumps, and you can’t have one without the other.
