Best Answer

The primary difference between the effects of rep ranges on the adaptive response depends on whether the load affects neural factors (low reps) or metabolic factors (higher reps). When you train with low reps (1 - 5), the adaptations that make you stronger are mostly neurological: You develop an increased ability to recruit more muscle fibers, you stimulate the higher threshold fibers that are not activated with high rep, low weight sets, you decrease neuromuscular inhibition, and there is increased coordination between the muscle groups. However, with low reps, the hypertrophy (size increase) of the muscle fibers is minimal.

In other words, reps under 6 make you stronger, but they don't necessarily make you bigger because the strength gains come from adaptations in the nervous system - the muscle fibers and other muscle cell structures do not hypertrophy (enlarge). This explains why certain athletes, powerlifters and Olympic lifters can be wicked strong but they don't look as strong as they are.

When you train with medium reps (6-12) the adaptations are more metabolic and cellular and only moderately neurological. This is why 6-12 reps is the range most often recommended for bodybuilding and hypertrophy. You get bigger and stronger in this rep range, but your strength gains are not maximal. This explains why some bodybuilders look stronger than they are (and why they are often the brunt of jokes made by powerlifters and weight lifters; i.e. "big, weak, slow, useless muscles", ha ha).

When you train with higher reps (13-20+), the adaptations are mostly metabolic and cellular. This rep range produces local muscular endurance, a small degree of hypertrophy in certain cellular components such as the mitochondria and the capillaries, and very little strength.

There is not a distinct line where neural adaptations end and structural/metabolic adaptations begin; rather it is a continuum, like temperature or colors of a rainbow.

For example, when you train in the 6-8 rep range, the adaptations are still somewhat neural, but also metabolic/structural: In this rep range, you get excellent strength gains and also excellent hypertrophy. In the 8-12 rep range, there is still some neural adaptation, but less than the 6-8 range and much less than the 1-5 range. The advantage of the 8-12 rep range is that you get maximal hypertrophy (this is the best rep range for pure size increases when strength is not the number one concern). You will also get stronger, of course, but not nearly to the degree as you would training with lower reps.

Rep range Percent of 1 rep max Training Effect Goal desired1-5 reps85-100%NeuralStrength & power, little hypertrophy6-8 reps75-85%Neural & metabolicStrength & Hypertrophy9-12 reps70-75%Metabolic & NeuralHypertrophy & some strength13-20+ reps60-70%Metaboliclocal endurance, some hypertrophy, little strength

Now, what exactly happens inside the muscle to make it get bigger and not necessarily stronger? Quite simply, ALL the structures inside the muscle cell grow when exposed to the appropriate training stimulus.

Remember back in high school when you had to memorize those diagrams of cellular anatomy (or you would get an F in the class)? There were all kinds of organelles and cell structures such as the endoplasmic reticulum, the mitochondria, the Golgi complex, ribosomes, centrioles, Lysosomes, and cytoplasm. Remember all that stuff?

If you're anything like me, you defied your Biology teacher to explain the reason why you had to memorize all that crap and what good it would do you in the "real world." Well, now that you're in the "real world" and you want strength and muscles, here you go:

A muscle cell has all the same cell structures as other body cells, and they all take up space. When speaking of the muscle cell, you mostly hear about the mitochondria (the cellular powerhouse where energy production takes place), the myofibrils (the actual muscle fibers themselves) and the fluid inside the cell (called cytoplasm in other body cells, or in the case of the muscle cell, its called sarcoplasm).

Myofibrillar hypertrophy is caused most effectively in the 6-8 rep range. This contributes to the most visible increases in muscle mass and cross sectional width. However, that doesn't mean you should only train in the 6-8 rep range. If you want to make the other "stuff" in the muscle cell grow as well, you should train in all rep ranges. The mitochondria and sarcoplasm also take up a substantial amount of space in the muscle cell and they are best stimulated with high reps. High rep training can also stimulate increased capillarization in the muscle (just ask former Mr. Universe and Mr. Legs himself, Tom Platz, about the effectiveness of high rep leg training done in addition to the low and medium rep training).

In addition, there is more than one type of muscle fiber: you have slow twitch (type I) and fast twitch (type IIa and IIb). Slow twitch muscle fibers also hypertrophy from higher reps (although they have the least potential for size increases, which is why you should spend more time below 13 reps if it's muscle mass you're after).

So here's the take home lesson: If you're an athlete and your primary goal is strength and power for improved sports performance, then a good majority of your training is going to be in the 1-5 rep range. This will help make you stronger, faster and more powerful without adding muscle bulk. If you're a bodybuilder and your primary goal is muscle mass, then the majority of your training should be done in the 6-12 rep range, but you should also do a little bit of training in the 3-5 rep range for power and strength, which will later facilitate hypertrophy (and prevent the powerlifters from making fun of you), and you should do a little bit of training in the 13-20+ rep range to facilitate the development of slow twitch muscle fiber, build mitochondrial density and increase capillarization


User Avatar

Wiki User

โˆ™ 2011-09-12 21:51:11
This answer is:
User Avatar
Study guides


20 cards

What is the effect of exercise on your flexibility

What is the fibrous connective tissue that holds bones in a joint together

What type of muscle straightens a joint

What type of disease is cystic fibrosis

See all cards

Heart Rate

20 cards

What were the cities and years of the Olympic Games which had terrorist disturbances

What is the correct definition for recovery heart rate

When is the ideal time to take a resting heart rate

What is another name for non-traditional sports

See all cards


20 cards

What is the difference between aerobic and anaerobic fitness

What is another name for non-traditional sports

Which of the following is a way that you can exercise for this course

How can you increase the number of calories you burn

See all cards

Add your answer:

Earn +20 pts
Q: How does muscle develop?
Write your answer...
Related questions

What is the best exercise to develop muscle?

Lifting weights,is the best way to develop muscles!

How does exercise develop muscle?

Exercise developes muscle by working and making the muscles grow to expand

Do muscle fatigue usually develop from an accumulation of hydrochloric acid?

do Epimysium surround an entire muscle

What organelles are important to the muscle system?

The nuclei is one organelle that is important to the muscle system. This is because the nuclei helps the muscle system develop.

What muscle group does bar dips develop?


How do you get muscles as a kid?

you are born with all muscle groups, you just have to develop them. healthy kids that eat a balanced diet and are active will develop whatever muscle groups getting the most use. there is debate over the medical risk of adolescents and weight training for muscle gain.

Why are you not building any muscle?

i think it depends on your workout of your muscles. Workout should be precisely on the muscle that you want to develop.

What type of muscle fibers you need to develop for weight lifting competition?

Mary needs to develop her fast muscle fibers. In order to do this, she will need to have frequent, brief and intensive workouts. She also needs to create muscle hypertrophy which will create an enlargement of the stimulated muscle. She can gain this by repeated and exhaustive stimulation which will create more mitochondria.

How do you use calisthenic in a sentence?

Calisthenic exercises & workouts, depending on how they are performed, can be used to develop flexibility, muscle strength, muscle endurance, and/or muscle power.

How long does weight training take to develop muscle?

To devloping the muscle is not an easy task. It is a hard thing to devloping the muscle. A person who wants to devlope the muscle had try hard for that push ups, pull ups etc excercises are very helpful to devlope the muscle. stacklabs provides legal steroids, bodybuilding suppliments and muscle enhancement products which devlope your muscle. To develop the muscle in short time or long time is totally depends on the body capacity and on the person who want to make a muscles.

Where does muscle tissue develop?

Muscle tissues are derived from the mesodermal layer of the embryonic germ cells through a process called myogenesis.

What is the short name for a shoulder muscle that bodybuilders develop?

delt Deltoid.

What is the scientific name of the muscle cell?

The scientific name for a muscle cell is a myocyte. Myocytes are also sometimes called muscle fibers. They are long, tube shaped, cells that develop from myoblasts.

How long does it take for muscle to develop after weight training?

Usually muscles develop or grow in the 24-48 hours post workout if you supply it with sufficient protein to help it grow and recuperate. Also, in the next 24 hours after the workout you must not work out the same muscle group to ensure that you do not overtrain the muscle group.

Mary wants to enter a weight lifting competition and consults you as to what type of muscle fibers she needs to develop and how she should go about it What would you suggest to her?

Mary needs to develop her fast muscle fibers. In order to do this, she will need to have frequent, brief and intensive workouts. She also needs to create muscle hypertrophy which will create an enlargement of the stimulated muscle. She can gain this by repeated and exhaustive stimulation which will create more mitochondria.

The that develops during gastrulation will later develop into bone muscle and circulatory structures?


What are the benefits of consuming Cytosport muscle milk?

There are many benefits of consuming Cytosport muscle milk. Benefits of consuming Cytosport muscle milk including fueling one's workouts and helping one to develop muscles.

When do human babies develop motor control?

Human babies develop motor control over a period of time after their birth. Some develop motor controls faster than others. Most babies first develop neck muscle motor control.

How does polymyositis progress?

Muscle wasting or shortening (contracture) may develop in the arms or legs. Heart abnormalities (electrocardiogram (ECG) changes, arrhythmias), develop in about 30% of patients.

Which layer forms during gastrulation and will later develop into bone muscle and circulatory structures?


What layers form during gastrulation and will later develop into bone and muscle and circulatory structures?


What process best explains how a nerve cell and a muscle cell can both develop from the same fertilized egg?


Do muscles develop on both male and female during puberty?

Yes, they develop on both. In males it is more evident as testosterone triggers more muscle growth than estrogen

Does increased muscle density mean more myofibrils per muscle fiber?

Yes, it means that you will gain more myofibrils per muscle fiber. A muscle fiber is a muscle cell, and everybody has about the same number. When you train your muscles, they will develop more myofibrils inside the muscle cells. So you cannot change the number of muscle fibers, or cells, but you can change the number of fibers, or myofibrils, inside them. The end result is more muscle density, not more muscle cells.

How do nerve cells go through mitosis?

Muscle cells grow and develop, but they do not go through mitosis.