Muscle Building

And now, for the meat of this newsletter. So far, I’ve written about health, flexibility, and other topics, but not about muscle building, so let’s talk about that.

The scientific term for muscle building is “hypertrophy.” There are two different types of hypertrophy:
– Myofibrillar
– Sarcoplasmic

Here is the difference: with myofibrillar hypertrophy, the actual muscle fibers get bigger. This usually happens with training protocols that involve lifting heavy weights (70–100% of 1 repetition maximum) for low numbers of repetitions (5 or less). When you see Olympic Weightlifters or powerlifters, that’s the primary type of hypertrophy that they have.

With sarcoplasmic hypertrophy, the fibers stay the same size, but the fluid surrounding the fibers (it’s called the “sarcoplasm”) increases. This usually happens in response to lifting moderate weights (50–80% of 1 repetition maximum) for moderate to high numbers of repetitions (8–20). This is most commonly seen in bodybuilders.

So if your goal is to increase your muscle mass, and you’ve been consistently following a protocol that involves sarcoplasmic hypertrophy (the classic 3 sets of 10), switch to a protocol that focuses more on myofibrillar hypertrophy, and vice versa. This will keep you progressing a lot longer.

For those of you who don’t care too much about muscle building, there are other health benefits to doing training aimed at muscle building.