11 Age-Defying Muscle Building Rules for Lifters in Their 20s, 30s, 40s, 50s and Beyond

I started weight training at age 14, and have been pretty intense with it since high school football (15+ years and counting). The rules that I followed applied to me in my 20s and now into my 30s. But as more people begin lifting later in life, these continue to be critical.  Many of my clients are in their , 40s, and some are in the 50+ range, and I have found that nearly every single rule holds true for them as well. (It’s also true for lifters in their 30s, and 20s.)


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If your interesting in building muscle and didn’t learn these techniques in high school or college, be  sure to brief yourself with these muscle building rules (I should call them commandments) as many, if not all of them apply as you get older. Note, that some of them will slightly vary as you age (such as emphasis on training frequency, recovery needs, etc.), which will be detailed below.

Jump ahead:

If you’re in your 20s

If you’re in your 30s

If you’re in your 40s

If you’re in your 50s and beyond


11 Rules for Muscle Building (at any age)

Below are 11 rules to follow when looking to increase lean muscle and strength. As you age, some of these demand more emphasis, so be sure to look at how each age range should properly attack their training and recovery in the below sections.

1. Make Mobility a Top Priority

If you move poorly, neglect mobility, and “push through” aches and pains chronically, you are basically a ticking time-bomb waiting to explode. Most gym injuries  are the result of overuse issues, with the littlest and most mundane of things finally “breaking the camel’s back”. A general rule of thumb is to address mobility and flexibility needs first thought stretching and warming up. Before you go all He-Man on the weights, first make sure you master these mobility drills.

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2. Do Compound Exercises for Strength and Muscle Mass

Large, compound movements (squats, deadlifts, rows, presses, carries, pulls, etc.) are the foundation for building stronger bones, muscular strength and size, and enhancing neurological function necessary for later stages of development. Without compound movements as a basic component, most programs will fall short of offering training muscle strength, bone health and density, increased testosterone, and results. This is not to say it cannot be done, however it is much more difficult to add sufficient muscle mass without them.

3. Do Unilateral Movements As Well

Unilateral training refers to single leg or arm movements, such as lunges, single-arm presses, and one-arm rows. Unilateral exercises have been shown to increase muscular engagement and growth, and they play a critic role in overall mobility, health and longevity as well.

When performing unilateral movements, you force the body to adapt via increased balance and muscle coordination, and to develop new muscle tissue that otherwise would go untouched when trained on two feet or two arms (such as with a barbell squat, done on both feet).

By increasing single-sided strength and muscular development, you can maximize muscle growth and minimize muscle and movement imbalances that often lead to sidelining injuries due to overuse.

Note, that this is not saying you cannot (or should not) use barbells, but rather to be sure to include unilateral exercises to better develop an athletic and healthy body.

If you are looking for a functional fitness program that includes both strength, muscle building, and unilateral exercises, join our functional fitness and strength workout app, compete with four workouts per week, exercise videos, and more.

4. Keep Repetitions in Moderate Range for Muscle Growth

The standard for muscle hypertrophy (growth) is lifting within repetition ranges of 8-12 reps to near failure. Lifting with heavy weights, and doing so often, can do wonders for strength development. However, this regimin lacks the metabolic effect of longer-duration sets (like reps of 8+) that signals muscle hypertrophy and protein synthesis.

The goal when training for increased muscle mass and size is to use a “heavy-ish” load that elicits a “muscle pump”, or feeling fullness in the muscle belly. The easiest way to describe “the pump” is when your muscles are full, hard, and you have a sense that the muscle is larger creating a tight, tone feeling]. This is most often done with a combination of higher repetitions sets (8-12 reps, or sometimes more) and moderate to heavy loads. This, paired with timed rest periods of 30-90 seconds has been shown to increase muscle hypertrophy and increase hormonal response of growth hormone and testosterone. This 9-week strength-hypertrophy cycle is a perfect combination of power, strength, and muscle hypertrophy movements. 

5. Lifting Heavy Weight Can Help

While lifting in the moderate rep range is highly beneficial for muscle growth, there are times when adding more weight and dropping the number of repetitions to between 2 and 5 should occur. For starters, adding more weight will increase strength, which over time will increase the amount of weight you can move for moderate rep ranges, as your top-end goes up. This equates to more training volume (sets x repetitions x load), a significant factor in muscle growth.

Increasing the amount lifted will also increase the neurological and muscular demands in the body, forcing the body to upgrade with muscle firing and activation patterns, both enhancing the amount of active muscle tissues.

Lastly, heavier loads can play a huge role on hormonal (testosterone) response, however be sure to not overdo it, as too much can result in blunted anabolic processes (increase stress hormone, decreased testosterone and recovery, sleeping issues, irritability, loss of libido, etc) and recovery.

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6. Listen to Your Body

There are times to push yourself, and times to pull back. When we are younger we can get away with “pushing through” things like lack of motivation, sleep, crappy nutrition, poor movement and form, etc. Younger people possess a natural resilience and, as you age, your margin for error shrinks. Over time, anything you do that your body is uncomfortable with will  put you in danger of  injury or other  setbacks. Listen to your body, and if you are having mixed emotions (such as things just feel crazy, all of your joints hurt), stop, take a few more minutes to warm-up properly, scale the weight back a few pounds, and focus on the movement and enjoying the progress. One day, week, or even a month of scaled back training won’t kill your chance of meeting long-term goals nearly as bad as a full blown injury.

7. Get Your Zzzz’s

Sleep is key to recovery. You have heard this time and time again, and that is due to the simple fact that it's 100% true. If you sleep like crud, over time you will feel like crud. Your training will turn cruddy, your hormones will turn you into a zombie, and your body and mind will start to form into mush. Get your zzz’s in anyway you can, as sleep will improve recovery from training, build new muscle tissue (when those processes are active), and help your anabolic hormones surge.

8. Drink A Lot of Water

Proper hydration is key to building muscle as it can improve blood flow to damaged muscle tissues, aid in recovery, keep joints and capsules operating smoothly, and increase your lifting performance. Chronic and acute dehydration can result in muscle weakness, slower cognitive and neuromuscular function, decreased performance, fatigue, and lack of recovery; all of which can lead to body fat gain, increased cortisol, and injury. Shoot for a gallon of water per day, at least (Tom Brady, age 40, does it, and he’s basically immortal at this point).

9. Stretch After Workouts

If you are unsure as to the difference between stretching versus a dynamic warm up, be sure to refer to this guide. Performing the classic stretch and hold that we so often associate with “warming-up” (called static stretching) should really be done after workouts, when your muscles are warm. Being supple allows for the body to recovery properly, aid in muscle and tissue blood flow, and help you feel pain free. All it takes is 10-15 minutes per day, in one or two session (after workouts) to reap the benefits. Here’s of of my favorite stretching routines (15 minutes) that I do a few times per week that really has helped keep my hamstrings, lower back, and joints operating smoothly).

10. Do Not Neglect Nagging Injuries

The more experience you have training, the more opportunities you will have to injury yourself (either a trauma or overuse injury). While the best route is to avoid overuse and traumatic injuries from happening in the first place (such as doing programs that balance movement, mobility, strength, and functional exercise), accidents do happen. A nagging injury can really hinder your ability to develop as a lifter. If something continues to be painful or feel off over a long period of time, see a doctor. If a nagging pain is due to soreness and overuse, however, you can  address this with light stretching and massages. If you are serious about your health and training, having a massage therapist or trained fitness professional on call can really help you. (I have a meet coming up, and just set up a time for a massage, in fact.)

11. Eat Protein, Fats, and Carbs

There should not come as a shock to anyone here, but nutrition is vital to muscle building, recovery, and obtaining a lean, athletic look as one ages. The instant I turned 30 it seemed as if my body changed, and it was no longer easy to recover from a few drinks the night before a serious workout or bounce back from a few cheat meals during the holidays. Those warnings fell of deaf ears while in my teens and 20s, but they are true nonetheless. That said, a well-balanced diet focusing on lean protein sources, fats, and not over-consuming refined carbohydrates like breads, pastas, sweets and baked goods, juices, sodas, etc. is key! The nutrition rules do not change as you age, however you must pay close attention to certain aspects of your diet because you will not have the luxury of letting things slide as much as you did when you were younger.

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Muscle Building in Your 20s

Building muscle in your 20s is very similar to building muscles in your teens. At this point in your life (assuming you started when I did) you have been training for a few years and have mastered the basics of muscle-building. If that’s the case, you have developed a great foundation and have the ability to really push yourself, increasing your volumes and loads lifted, and still maintaining the ability to recovery pretty well.

Though nutrition and sleep are more forgiving, you can really maximize your results by taking advantage of the fact you most likely don’t have the life stresses (work, supporting a family, paying a mortgage) of people in later stages of their lives. This means training correctly, taking all the necessary time to prepare foods, eat healthfully, stretch, and get the sleep you need.

This period of your lifting life is a fruitful one, and you should not take it for granted! That said, if you are like me or my clients and are in your 30s, 40s, 50s and beyond, do not fear. Great things are still to come, I promise :)

Muscle Building in Your 30s

If you find yourself in your 30s and are a beginner, I suggest you download this muscle building PDF e-guide, which 100% still applies to you, regardless of age. That said, you most likely will have some pre-existing movement and mobility issues and injury concerns that should be addressed before jumping into a full-blown training program. Investing in a coach or qualified fitness professional for an assessment and/or a few training sessions is most likely your best option for diagnosis and actionable insight.

If, however, you were diligent in your teens and 20s, your 30s can be some amazing years for you in terms of muscle growth, strength, and fitness. For you, experience is on your side, as you have built mind-muscle connections, solidified sound movement patterning, technique, and muscle mass. You have also learned a thing or two about what worked for you and what doesn't, as intuition is one of the greatest ways to build muscle and avoid injury.

The above rules still apply to you as well, however you need to be more conscious of recovery, listening to the body, nutrition, sleep, and addressing any nagging aches and pains. Hitting new PRs in terms of weight can and should still happen, just realize that the margin of error is shrinking. Just don’t try to max out y our weights every time you walk into the gym...

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Muscle Building in Your 40s

At this stage in life, you probably picked up a few injures or perhaps you’re not moving as well as you used to, either from a less active lifestyle or simply by doing the same workouts year after year. If you come into your 40s pain-free and full range of motion movement, you're off to a great start. If however, you are looking to kick-start fitness at this stage with a less than solid foundation, you need to understand your limitations.

As we age, we become a little less resilient.  Recovery from hard training becomes harder, and the toll from drinking alcohol and poor nutrition becomes greater. The margin of error has shrunk from when you are in your 20s and 30s and therefore you need to be smarter than going into the gym and doing random workouts or the same exercise you did years ago.

I suggest you do a reset of sorts, going through your body and taking notes on any nagging aches, pains, or movement imbalances. Start there. Neglecting these warning signs will be much more detrimental to you than a 20-year old. You are more likely to strain muscles and have chronic overuse injuries, so just be sure to train smart, train hard, and place extra emphasis on warm-ups, stretching, and self care (massage, hot baths, etc).

Muscle Building in Your 50s and Beyond

Similar to other age groups, your fitness and health coming into this age range makes all the different in your biological and physiological “age”.

The secrets to muscle building are the same as they have been for years, however you must understand and be realistic with expectations, as it is no secret the hormones flowing through your body are not as high as a teenager's at prom.

What you have on your side, however, is experience, knowledge of your body, and the understanding that fitness and muscle building is far more than just an aesthetic pursuit. The stronger, more muscular, and healthier you get the more protection you have from injury, illness, and a decreased quality of life.

Emphasis on recovery, stretching, and a balanced workout program that includes strength training, cardiovascular fitness, and balance/coordination movements (such as unilateral exercises) should all be emphasized.

Muscle Building Recap

At the end of the day, growing old will happen to all of us. As we age, we become wiser and more in tune with our bodies (hopefully), which can drastically impact our fitness and help us prevent injury. We are less likely to make stupid mistakes or horse around.

Building muscle is not just a young man’s game, as research has shown that muscle hypertrophy can occur in men and women 75+ years old!

Adopting the principles above as early as possible will allow you to approach the next stage of life in better shape (mentally and physically), which can drastically improve your success and quality of life.

For more muscle building information, be sure to check out the articles and links below!