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  • Hey guys, Amy here on DNews answering your questions about muscles! Neko recently asked

  • us if we can make a video about why our muscles grow big when we exercise.

  • We all want to get big and strong, building muscles to have lean bodies and to be able

  • to squat our coworkers for funsies. But what actually happens when you workout that makes

  • your muscles grow?

  • There’s more to muscles than you might think.

  • We have different types of muscles: cardiac, smooth, and skeletal muscles. Smooth muscles

  • are responsible for the contracting movements of hollow organs like blood vessels, the gastrointestinal

  • tract, bladder, and uterus. Skeletal muscles are made up of bundles of individual muscle

  • fibers that are themselves strands of proteins that grab onto one another and pull. These

  • muscle are attached to bones, and it’s the contraction, that pulling, that causes your

  • bones to move around your joints. That’s what happens when your muscles contract. These

  • are controlled by the somatic nervous system. The cardiac muscle, the one that makes your

  • heart pump blood throughout your body, is involuntarily controlled.

  • Your heart and the muscles that control it are obviously an important part of working

  • out or playing sports, but when were talking about building muscles we need to focus on

  • skeletal muscles.

  • There’s a little more to skeletal muscles than just the fibers that make them up. Muscle

  • are broadly categorized into two types. Type I or slow twitch muscles are more efficient

  • at using oxygen to generate energy. And as the name suggests they can work longer before

  • being exhausted so these are the ones that you use for duration sports like long distance

  • running. Type II or fast twitch muscles rely on anaerobic metabolism to create fuel, or

  • more simply, they use your body’s stored energy for shorts bursts of activity. These

  • are the ones your body uses when sprinting or weightlifting.

  • When you build muscle, youre actually breaking down these muscle fibres and building them

  • back up.

  • There are a couple of ways to do this. Hypertrophy is an increase in the size of the muscle due

  • to an increase in the size of the muscle fibers; while hyperplasia happens when you actually

  • split muscle fibers to eventually grow more of them, though some trainers suspect that

  • this splitting doesn’t actually create new fibers, it just changes existing ones.

  • The exact process of muscle growth isn’t entirely understood, but leading theories

  • say that lifting something heavy, like a weight, breaks the muscle fibers apart, and then those

  • fibers grow back in a way that allows them to compensate for the damage and protect themselves

  • against future damage. This happens naturally, but lifting speeds the cycle up so you rebuild

  • muscle faster, and the more you breakdown the more you grow back!

  • Which is why you need to rest between workouts; you need to give your body time to repair

  • itself, and help that process along with protein. And that’s where the increase to muscles

  • comes from.

  • Speaking of bulking up,Toyota has been doing some augmentation of their own with the TRD

  • line of Toyota Trucks. Enhanced to rule the off-road!

  • So does this clear things up or do you still have more questions about muscles?

  • Let us know in the comments below or on Twitter @DNews. And of course, for more DNews every

  • single day of the week, don’t forget to subscribe!

Hey guys, Amy here on DNews answering your questions about muscles! Neko recently asked

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