How does building muscle work?


How does building muscle work?
How does this differ if your exercise is higher reps at lower weight vs. Tons of weight with a 1 rep max?

In: Biology

Your muscles are made of 2 types of fibers: fast twitch and slow twitch. Working out pulls some of the fibers apart a little, which makes your body add more fibers to repair them. More fiber means more strength or endurance.

Low weight high reps is slow twitch fiber. They don’t fatigue as fast, but aren’t as strong. It builds endurance. High weight low reps is fast twitch fiber. They fatigue much faster. It builds strength.

If your workout is running, then long distance is slow twitch, and sprinting is fast twitch.

Every type of exercise builds your muscles. However, certain set/rep combos are better for certain goals. Doing one-rep-max exercises over and over just aren’t very efficient.

5-rep sets are best for strength. 10-rep sets are best for hypertrophy. 15-rep sets are best for endurance.

So, for example, if you did 5 sets of 10 (5×10) you would build strength, but not as efficiently as if you did 5x5s.

Great explanations so far, to add to them the 1 rep max (1RM) is typically a goal for your strength building program to achieve. When starting a strength based exercise regime your goal becomes to continually increase your 1RM as proof that your progress continues. 1RM should in no-way be considered as exercise even though it is an extremely strenuous activity, this is because the damage incurred by repetitive max lifting is a guaranteed way to end up with chronic musculoskeletal disorders.