Hi Jordan or Austin, I’m an older lifter (58 now – started when I was 55) – some time ago, I came under the influence of the work “Younger Next Year” – and there is a section in this work by Dr. Henry Lodge that really was striking to me. But I have not seen this particular aspect discussed from a medical perspective in any subsequent work – and it does not seem to be mentioned in the “Barbell Prescription” work by Baker and Sullivan. Could you discuss the medical aspects of this? Is this a real thing? Has this been discussed anywhere else in any of the literature you read? Have you guys discussed it? And if this is indeed the case, how would strength training affect this process in ways other than what aerobic training might affect it?
You have two information superhighways in your body: your nervous system and your circulatory system. It may come as a surprise that your bloodstream carries information, but it does. Plasma, in particular, is a complex, living river of thousands of chemicals and proteins signaling and controlling virtually every aspect of your body: growth, decay, mood, immune function, cancer surveillance, fat metabolism, sexuality, joint health … and it all operates through inflammation and repair.
Here’s how it works: When your cells sense damage, say, from exercise, they automatically release chemicals to start the inflammation—to set the stage for repair. A few of those chemicals leak into the bloodstream, and those few molecules draw white blood cells to the injured area the way blood in the water draws sharks from miles around. After the inflammatory cycle has done its demolition work, the white blood cells go away, leaving behind a clean, fresh surface so the construction crews can get to work on the growth part of the cycle.
This chemistry is at the core of the new science we talk about in this book, so let’s go into more detail here. The proteins that control inflammation are called cytokines, and they regulate every aspect of your biology. Cytokines are messenger molecules. They turn on or off virtually all the metabolic pathways in each tissue and cell in your body. Each tissue has its own specific cytokines, but they cross-react to coordinate growth or decay throughout your body.
Hundreds, perhaps even thousands, of cytokines are at work in your body, regulating growth and decay down to the most microscopic level. For the purposes of this book, however, imagine that there are only two cytokines in your whole body—two master chemicals that control growth or decay in every tissue and cell. It’s a massive simplification, but surprisingly accurate. We’ll call these chemicals cytokine-6 and cytokine-10 …
Cytokine-6, or C-6 for short, is the master chemical for inflammation (decay), and cytokine-10, or C-10, is the master chemical for repair and growth. C-6 is produced in both the muscle cells and the bloodstream in response to the exercise, and C-10 is produced in response to C-6. This is your body’s brilliant mechanism for coupling decay and growth. C-6 actually triggers the production of C-10. Decay triggers growth.
Now let’s take a fresh look at the power of exercise to change y our whole body in light of this new information. You have 660 muscles, which make up almost 50 percent of your lean body weight. Those 75 or 100 pounds or muscle are a massive reservoir of C-6 and C-10, a massive reservoir of potential youth if you do your part. Exercise triggers repair, renewal and growth by producing C-6. All forms of aerobic exercise produce C-6 in logarithmic proportions to both the duration and intensity of exercise. In marathon runners, the level of C-6 rises a hundredfold by the end of the race. It is an automatic measure of how much exercise you do, how much inflammation you cause and how much growth you will experience. In other words, how much C-10 will be released.
C-10 is key, because growth is the magic you are after. But growth is too complicated for neat description. Demolition is easy to describe, because, while it’s important that you don’t hit a gas main or anything, it’s basically sledgehammers and dumpsters. But growth is blueprints, and master carpenters, and electricians, all controlled by C-10. We’re not going to go into the fine details of how the cytokines actually do this … but you will see C-10’s effect as you build your stronger, healthier, younger body. The most important thing to understand about C-10 is that it is automatically turned on by C-6. Inflammation controls growth: that’s the critical concept. C-6 peaks right after the marathon and turns on the cytokines that control repair, which peak an hour or so later and which stay at higher levels for hours after exercise, repairing your body.
At rest, only 20 percent of your blood flow moves through your muscles; in a trained athlete, that rises, with exercise, to 80 percent. Picture it: torrents, rivers of blood flooding through your muscles with exercise, picking up the cytokines, the messages of inflammation and repair, of growth and healing, and taking them to every corner of your body. From the top of your head to the tips of your toes. From your heart to your prostate, fingers to knees. Every joint, every bone, every organ, every tiny part of your magnificent brain gets its bath of C-6, and then the wonderful, rejuvenating C-10 each time you sweat. That’s the right balance, good decay triggering growth. [Younger Next Year, pp. 67-ff.].