Welcome back to the Barbell Medicine podcast. I'm Dr. Jordan Feigenbaum. I hope you've

had a great week so far. Today, on episode 259, we're going to talk about what happens

when someone stops working out. In other words, how long does it take to lose muscle,

strength, and how does it happen? To start, let's talk about how our muscle and strength

gained. For strength, strength is defined as the amount of force produced measured in a specific

context. For example, a power lifter completing a heavy one-ramp maximum, their 1RM,

is displaying force production in one context where as a gymnast or shot put thrower,

is displaying force production in another. In short, there are many different types of strength

that are linked together by the common feature of muscular force production. Improvements in

strength are the result of both structural and neurological adaptations, sometimes called

peripheral and central adaptations, or may structural or peripheral standpoint. Muscle

fibers get bigger, tendons become stiffer, and store more energy to support force production.

In addition to these structural changes, neuromuscular adaptations include increasing the frequency

of the electrical signal that travels from the brain and the spinal cord to the muscle,

which makes the muscle create more force. Additionally, more muscle fibers are called upon

to create force, a process known as motor unit recruitment, and finally, the efficiency and

coordination by which motor units create force through complex movements also improves.

To sum it up, we gain strength by improving the muscle's ability to produce force

through both structural and neurological adaptations. On the other hand, hypertrophy is defined

in most studies as an increase in the total mass of a muscle, whereas a decrease in total mass

of a muscle is referred to as atrophy. Now, each muscle fiber is made up of thousands to hundreds

of thousands of muscle fibers, and in general, it is thought that the number of skeletal muscle

...