The average man in the gym who is lifting weights probably wants to not only lose fat, but also gain some muscle.
The article covers the topic of how muscles grow, with a focus on why women generally don’t bulk up when lifting weights. It explains the science behind muscle growth, detailing the role of hormones, muscles fibers, and protein intake. The article also busts some common myths about women and muscle growth, such as the belief that lifting weights will make them look manly.
Skeletal muscles are the type of muscle that we will be discussing. They are made up of myofibrils and sarcomeres that form a muscle fiber. These are the basic units of contraction.
The human body has 650 muscles that contract when receiving signals from motor neurons. The strength of these signals determines how strong the muscle contraction will be. Motor neurons are triggered by the sarcoplasmic reticulum, which is a part of the cell. The better you become at having the signals from the motor neurons tell your muscles to contract, the stronger you can get.
Even though powerlifters may not look as muscular as bodybuilders, they are able to lift heavier weights because they have learned to activate their motor neurons and contract their muscles more efficiently. When people first start lifting weights, they see the most initial strength gains because they are still learning how to use their muscles effectively. After they have practiced for awhile, the gains become more steady because they have an easier time activating their muscles.
The Physiology Of Muscle Growth
Assuming you are asking for a summary: The body repairs damaged muscle fibers by fusing them together to form new myofibrils. This process is called muscle hypertrophy, and it occurs while the person is resting, not while they are working out.
Satellite cells can help a person add muscle mass by adding nuclei to muscle cells and contributing to the growth of myofibrils. Those who have more satellite cells may find it easier to add muscle mass than those who have fewer of these cells.
The most interesting study in the past 5 years has shown that those who were “extreme responders” to muscle growth, with an incredible 58% myofiber hypertrophy from exercise, had 23% activation of their satellite cells. What is interesting to note, though, is that some people known as “non-responders” in the study had 0% growth and had a concurrent 0% activation of their satellite cells. Therefore, it seems the more you can activate these satellite cells, the more muscle growth you’ll be able to achieve. So then the question becomes, how do you activate these satellite cells to increase muscle growth?
3 Mechanisms That Make Muscles Grow
The ability to continually put more stress on muscles is the underlying cause of natural muscle growth. This stress disrupts homeostasis within the body, which causes three main mechanisms that spur on muscle growth.
1. Muscle Tension
If you want to see muscle growth, you need to put your body or muscles under more stress than they are used to. The best way to do this is to lift heavier weights over time. This extra tension forces the muscles to change chemically, which activates growth factors like mTOR and satellite cells.
The muscular tension affects the connection of the motor units with the muscle cells the most dramatically. Two other factors help explain why some people can be stronger but not as big as other people.
2. Muscle Damage
If you’ve ever experienced soreness after a workout, it is because of the localized muscle damage that occurred during the workout. This damage causes the release of inflammatory molecules and immune system cells, which in turn activate satellite cells. Soreness is not always present, even when the muscle damage is. over time, soreness is typically reduced by other mechanisms.
3. Metabolic Stress
The sensation of a “burn” or “pump” during exercise is caused by metabolic stress. In the past, scientists were skeptical when bodybuilders said that this feeling resulted in increased muscle size. However, after further investigation, it appears as though they were correct.
Metabolic stress causes cells to swell around the muscle, which can help contribute to muscle growth, without necessarily increasing the size of the muscle cells. This is because of the addition of muscle glycogen, which helps to swell the muscle, along with connective tissue growth. This type of growth is known as sarcoplasmic hypertrophy, and is one of the ways that people can get the appearance of larger muscles without increases in strength.
How do hormonesaffect muscle growth?
How Do Hormones Affect How Muscles Grow?
Hormones play a large role in muscle growth and repair because they help regulate satellite cell activity. Insulin Growth Factor 1 (IGF-1), in particular, and Mecho-Growth Factor (MGF) and testosterone promote muscle growth.
when working out with weights, people usually think about testosterone because it is the main hormone that increases protein synthesis, inhibits protein breakdown, activates satellite cells, and stimulates other anabolic hormones. Although most testosterone is bound in the body and therefore not available to use (up to 98%), strength training seems to help not only release more testosterone, but also make the receptors of your muscle cells more sensitive to your free testosterone. Testosterone can also stimulate growth hormone responses by increasing the presence of neurotransmitters at the damaged fiber site, which can help to activate tissue growth.
Here are six ways muscle supports your body and mind:
1. Muscle helps manage blood sugar.
An epidemic of diabesity (obesity and diabetes) has been created by high-carb diets combined with sedentary lifestyles. Prediabetic or diabetic, about two-thirds of the population is overweight or obese.
Obesity and diabetes aren’t always related. About 20 percent of people with diabetes or prediabetes are a healthy weight.
The two options to fix the blood sugar problem are to either eliminate carbs entirely or to eat a moderate amount of carbs and to create space to store them.
The more muscle you have, the more glycogen your liver and skeletal muscle can store. Without regular exercise, and specifically weight training, you lose this storage space and your blood sugar rises. As a result, your pancreas secretes more insulin to try to store the glucose as fat.
There is evidence to suggest that issues with blood sugar and insulin can lead to various health problems such as cancer, cognitive difficulties, heart disease, and premature aging.
More than one third of the population has a condition called prediabetes, which means their blood sugar levels are higher than normal but not high enough yet to be diagnosed with diabetes. Unfortunately, very few people who have prediabetes are aware of it. By 2025, it is estimated that 64 percent of the population will have type 2 diabetes.
2. Muscle builds strength and stamina.
The first few months of a weight-training program are mostly about your nervous and muscular systems getting better at using the muscle you already have, rather than building new muscle tissue.
Without building any muscle, you gain considerable strength. Then, after you reach the limit of your strength with your existing muscle, you start to build more muscle. After a few more months of weight training and a high-protein diet, you notice more shape to your body, and your strength continues to improve. You also notice that you can handle harder workouts and recover faster than before.
Although it’s fun to see your strength improve, the real benefit is how it makes your everyday life easier. For example, carrying groceries and going up stairs becomes easier. You can also have more fun with your grandchildren.
The growth of new muscle fibers and new energy-producing machines called mitochondria leads to increased strength and stamina. You produce energy more efficiently with more mitochondria.
As you workout, your ligaments, tendons, and muscles all become stronger. Additionally, your nervous system gets better at coordinating different muscle groups, making your movement smoother and more effective.
You will become weaker if you don’t work to improve your strength. If you don’t work to build muscle and strength, your body will break it down.
3. Muscle supports your joints.
Many people avoid weight training because they believe it will cause joint pain. However, not weight training is often the cause of joint pain. A better solution is to find a way to weight train without making your joint pain worse. If you keep at it, the weight training will eventually alleviate your joint pain.
Although squats might not be the best exercise for someone with osteoarthritis in the knee, where there is no cartilage between the bones, there are probably other exercises that would work better for them.
You shouldn’t avoid exercising because of pain in one area of your body. In fact, exercising can actually help relieve pain in other areas of your body.
If you have strong muscles, you are less likely to get injured from falling or slipping. Also, the hormones released from building muscle can help to repair other tissues and reduce pain.
4. Building muscle builds bone, too.
Experiencing physical tension or resistance stimulates the growth of muscle mass and bone density. After experiencing the stimulus, your body uses amino acids to build and repair muscle (along with other micronutrients), and uses protein, calcium, magnesium, and vitamins D and K to build bone.
Your body won’t build bone unless you stress it with resistance training, even though calcium, magnesium, and vitamin D and K are necessary for bone health.
If you’re losing muscle, it’s highly likely that you’re also losing bone density. However, if you do what’s necessary to build muscle, you’ll most likely improve your bone density as well. Having strong muscles usually means having healthy bones.
5. Muscle helps you control body fat.
Muscle requires more calories to maintain than fat, so as you add muscle and lose fat, you will see a change in your appearance even if the scale weight does not change. Your resting metabolic rate will also increase.
Although it may seem that way, age is not as big of a factor as diet and exercise choices. In fact, a healthy 70-year-old could have a higher metabolism than a sedentary 30-year-old.
Doing a lot of cardio and eating a low-calorie diet will not help you lose body fat. Instead, it will cause you to lose muscle and slow your resting metabolic rate. Strength training and a high-protein diet are better ways to build lean body mass.
6. Muscle may change your emotional state.
When you are feeling sad or depressed, your body posture may change to match those emotions. This can include slouching, dropping your head, or turning your arms inwards.
When you sit in the same position as someone who is depressed, you will begin to feel that emotion.
You can improve the ergonomics of your workstation, and also help alleviate some of the effects of poor posture, by building muscle in a balanced way.
