Building Muscle After 40: What the Science Says

If you want to know how to build muscle after 40, but you’re not sure what (if anything) you should be doing differently, this page will show you how.

Read a few mainstream articles on the subject of building muscle after 40, and you’d be forgiven for thinking that hitting 40 means immediately trading in your barbells and dumbbells for a mobility scooter and walk-in bath.

Does your workout routine need to be radically different once you turn 40?

The short answer to that question is no, it does not.

The fact you’re old enough to remember the opening theme music from TJ Hooker doesn’t mean that your program should involve nothing more strenuous than shoulder rolls, toe raises, and a few deep breathing exercises.

So if you’re in your forties, and you’re worried that you’ve left it too late to build muscle, I have some good news. You haven’t.

Can You Build Muscle After 40?

Yes, you can build muscle after 40. It’s not like the ability of your muscles to adapt and grow suddenly stops once you hit 40. In fact, if you’re currently out of shape and unfit, you’ll see relatively rapid gains in muscle mass when you start lifting weights.

For someone who is lean, fit and strong, gaining muscle and losing fat requires a significant chunk of time, effort and sweat. But if you’re currently fat and weak, you’ll be able to make progress a lot more quickly.

In one study, researchers rounded up a group of overweight and unfit men with an average age of 41, and got them to lift weights three times a week [1]. On top of that, the men also did 30 minutes of cycling or walking in the same workout.

This exercise routine put them in a calorie deficit, which means they were burning off more calories than they were getting from their diet.

After 14 weeks, the men had lost an average of 16.3 pounds of body fat. That’s a little over one pound of fat lost per week. 

But that’s not all. As well as losing body fat, the men had gained almost 10 pounds of lean body mass — a reasonable proxy for muscle mass — at the same time.

There’s more.

Blood sugar, triglyceride and insulin levels were down. HDL cholesterol (the so-called “good” cholesterol) went up. VO2max, a measure of cardiovascular fitness, had risen by over 25%.

Of course, the men wouldn’t have continued to make such rapid progress indefinitely. Over time, your results will tend to slow down. 

And no two people respond in the same way to an identical routine of diet and exercise, so nobody can say for sure exactly how fast you can expect to see results.

But this study does illustrate a very important principle: If you’re in your 40’s, out of shape and unfit, it’s possible to make big changes to your body in a relatively short period of time — 3-4 months in this case — as long as you’re willing to put the work in.

How to Build Muscle After 40

Building muscle after 40 is not easy. You probably have more stuff going on in your life than you did 20 years ago, which can make it harder to focus on eating right and training regularly.

You might feel that your body can’t handle the kind of punishment you used to dish out in your twenties, and takes longer to recover than it used to.

But none of this matters. With the right type of training, you can still build muscle and get strong well into your forties, fifties, and beyond.

The basic rules for building muscle after 40 are much the same as they were at the age of 30 or even 20.

Although the number of times you’ve traveled around the sun will affect the speed at which you progress, people of different ages respond to training in much the same way. It’s mainly the size of your results and the speed at which you attain them that varies.

I did say that your training doesn’t need to be radically different once you turn 40. Which is true. You certainly don’t need to change everything you’re doing.

But I do have a few quick ideas that will make your workouts more effective, leave your joints feeling better, and help you steer clear of injuries.

1. Train with Lighter Weights and Higher Reps

Keep on lifting heavy all the time, and you’ll eventually start to notice little aches and pains in your knees, wrists, elbows and shoulders.

Eventually, those minor niggles will get so bad that they interfere with your training. It will take weeks, maybe even months, before they clear up and you can train properly again.

The solution is very simple. If going heavy on certain exercises causes you pain, just go light and train in a higher rep range instead.

Despite what some people might say, it is possible to build muscle after 40 by training in a higher rep range with a lighter weight.

In fact, there are multiple studies showing that lighter weights and higher reps do a surprisingly good job at stimulating muscle growth.

In one trial, high reps and light weights (3 sets of 30-40 reps) stimulated just as much muscle growth as heavier weights and lower reps (3 sets of 10-12 reps) [4].

And this isn’t a finding that’s limited to untrained beginners, who tend to grow no matter what they do.

Even in guys with an average of four years training behind them, sets of 20-25 reps work almost as well as sets of 8-12 reps per set for triggering muscle growth [5].

Heavy weights… medium weights… light weights… all can be used successfully for building muscle after 40.

2. Choose Joint-Friendly Exercises

Training routines geared towards muscle growth usually focus on compound lifts like the squat, deadlift, bench press and so on.

These exercises work a large number of muscle groups at the same time, which makes them a highly efficient use of your time in the gym.

However, some people have a bone structure that makes them better suited to certain exercises than others.

You might not be built for deep squats with a heavy barbell across your shoulders, deadlifts from the floor, chin-ups from a straight bar or bench pressing through a full range of motion.

If you’ve got short arms and long legs, for example, you’re going to find it a lot harder to deadlift from the floor without rounding your back compared to someone with long arms and short legs.

But that doesn’t mean you should give up on the deadlift. Just do rack pulls instead, using a starting position that allows you to maintain normal spinal curvature.

If your wrists hurt when you’re doing chin-ups or pull-ups from a straight bar, use a suspension trainer. This allows your wrists to move freely rather than being locked in the same position throughout the movement.

If the bench press hurts your shoulders, use a “shoulder saver” pad, which shaves an inch or so off the bottom of the movement.

Or use dumbbells with your palms turned in and elbows moved closer to your body (this one simple tweak is often enough to get rid of shoulder pain almost instantly).

You’re still working the same upper body muscle groups, but you’re doing so in a way that’s a lot easier on your joints.

And don’t worry if you can’t squat “ass-to-ankles” without losing the arch in your lower back. Squatting to parallel, or even slightly above parallel, is good enough. If you don’t like squats, exercises like the leg press or Bulgarian split squat can be used to train your lower body.

Building muscle after 40 doesn’t require that you train through a full range of motion, especially if doing so causes you pain.

There are some exercises that will hurt no matter what. If so, don’t be afraid to ditch that exercise and find a similar one that doesn’t. There is no single “must do” exercise that can’t be replaced with something else.

3. Find New Ways to Overload Your Muscles

To build muscle, your focus should always be on improving your workout performance over time. You need to give your muscles a reason to get bigger, or you’ll remain stuck at the same size you are right now.

The way most people do this is to increase the amount of weight they lift in each exercise. Once you’re able to complete a set number of repetitions with a given weight, the weight goes up. But, as you get older, adding weight all the time becomes increasingly difficult.

What’s more, you’ll often find that your joints start to flare up as the weights get heavier.

What’s the solution? Do you keep on pushing through the pain? Or just accept that building muscle after 40 is an impossible job?

Adding weight to the bar isn’t the only way to overload your muscles. You can do more reps with the same weight, reduce your lifting speed, or employ techniques for extending a set, such as drop sets, static holds or rest-pause training.

All are highly effective ways to increase the amount of work your muscles are exposed to, which in turn will make them bigger and stronger.

4. Don’t Cut Back on Cardio

Some lifters fear cardio, mainly because they think it’ll make their muscles shrink.

However, most research shows that cardio doesn’t have a negative impact on muscle growth, just as long as you don’t do too much of it.

In fact, cardiovascular exercise may actually help rather than hurt your gains via an increase in the capillary density of muscle.

Capillaries are tiny blood vessels, which deliver oxygen, nutrients and hormones to muscle cells, as well as helping clear the metabolites that build up during exercise.

Here are some of the key findings from a review of the science looking at why some people build muscle faster than others [6]:

1. Men with a higher capillary density gained more muscle compared to individuals with lower capillary densities after six months of weight training.
2. Middle-aged to older subjects with low levels of muscle mass possess a significantly lower skeletal muscle capillary content compared to age-matched counterparts with more muscle.
3. A reduction in skeletal muscle blood flow may contribute to sarcopenia (age related loss of muscle mass and strength) due to a reduction in nutrient delivery.

In a follow-up study, six weeks of aerobic pre-conditioning was shown to accelerate gains in muscle size during a subsequent 10-week resistance training program [7].

The researchers also found a significant relationship between the degree of capillarization and muscle growth. That is, muscle fibers with the greatest capillary density were the ones that grew the fastest.

In short, an increase in capillary density may well improve your ability to build muscle, possibly via an increase in the quality of your workouts (improved recovery between sets and increased ability to fight fatigue), a faster rate of recovery from one training session to the next, an increase in the supply of nutrients to the muscle, or some combination of the three.

5. Warm Up Properly

Many in their late teens and early twenties will walk straight into the gym, do a few arm circles, and then jump straight into the heavy stuff.

If you’re over 40, this approach will get you injured sooner or later. You have to make time to warm up properly.

The exact warm up that you do will depend on what your workout looks like. It will also vary from person to person, depending on the environment you’re training in, how strong you are, and so on (I walk you through how I like to do it inside my MX4 training program).

While a good warm-up can reduce the risk of injury and improve your performance, it doesn’t need to last forever.

Foam rolling, dynamic activation drills and various “alignment” exercises can be useful at certain times and for certain individuals. But a lot of people are doing this stuff simply because they’re copying what everyone else is doing, rather than because it’s actually helping their workout.

6. Stretch What’s Tight

Static stretching has come in for a lot of criticism in recent years, mainly because it doesn’t do a lot of the things it’s supposed to.

Most research shows that stretching has little effect on muscle soreness, and doesn’t appear to do much for injury prevention either.

However, if you find that certain muscles feel a little “tight” (the hamstrings, hip flexors, quadriceps and glutes are the usual culprits), or there’s an “asymmetry” in flexibility (i.e. one leg feels substantially tighter than the other) then it’s worth experimenting with some static stretching to see if it makes you feel any better.

If you want a simple prescription for flexibility, aim to stretch any “tight” muscles for a total of 60 seconds per day.

Stretching for 60 seconds has been shown to improve flexibility more quickly than a 30-second or 15-second stretch in a group of subjects aged between 65 and 97, all with “tight” hamstring muscles [8]. What’s more, participants who stretched for 60 seconds remained more flexible for longer than subjects in the other groups.

One stretch lasting 60 seconds or six stretches lasting 10 seconds work equally well when it comes to increasing flexibility [9]. Regardless of the length of a single stretch, the key to improvement seems to be total daily stretch time.

Like most things, flexibility is also influenced by your genes.

There’s a gene called COL5A1, which is linked to your hereditary level of flexibility [10]. One version of the gene means you’re quite flexible, the other means you’re not. Which means that the rate at which your flexibility improves, as well as the point at which it stops improving, are not entirely under your control.

Nutrition for Building Muscle After 40

Nutrition is just as important for muscle growth as what you do in the gym. What should a diet for building muscle after 40 look like?

The two most important things to focus on are:

• Calories
• Protein

Synthesizing muscle tissue requires energy, and a diet designed to maximize your rate of muscle growth will involve eating more calories than your body needs to maintain its weight.

That means being in a small calorie surplus, rather than the calorie deficit required for weight loss. And by small, I’m talking around 10% more calories than you need to maintain your weight.

That is, if you need 2500 calories per day to maintain your weight, you’d aim to eat an extra 250 calories. This would take your daily calorie intake to roughly 2750 calories.

Compared with some of the old-school bulking diets you may have tried in the past, that probably doesn’t sound like much. But you can’t force your muscles to grow faster simply by stuffing yourself with food.

Extra energy that isn’t used to fuel your workouts, to help you recover from those workouts, or to power muscle hypertrophy, will just end up stored as fat. All of which you’ll need to get rid of at some point in future.

Rather than eating too many calories and having to burn them off again, it makes more sense just not eating them in the first place.

How much protein should you eat if you’re over 40 and want to gain muscle?

Aim for around 0.7 grams of protein per pound, or 1.6 grams per kilogram, of body weight.

For someone weighing 180 pounds (82 kilograms), that gives you a daily protein target of around 126 grams per day.

Going higher still and aiming for one gram of protein per pound of body weight or higher isn’t going to do you any harm, but I don’t think you’re going to see much of a benefit either.

Ideally, you’d have a dose of protein within the first few hours after waking up, before a workout, after a workout, and before going to bed.

As for fat, that can vary from 20 to 40 percent of your total calorie intake. And there’s no rule that says it has to be the same from one day to the next. Some days you might eat a little more fat, some days a little less.

Once protein and fat are taken care of, the rest of your calories should come from carbs. Ideally, most of those carbs should come from whole foods, which provide your body with plenty of vitamins, minerals and other nutritional benefits.

What about supplements?

Over the years I have used a lot of supplements, including herbal extracts, nitric oxide boosters, amino acids, and exotic stimulants to name but a few. 

Despite the hype, there are only a very small number of supplements out there worth using. And even then, the benefits are relatively modest. It’s rare that a supplement will overdeliver on its claims.

Creatine monohydrate is certainly worth using, as is a high-quality protein supplement (such as whey protein) and a basic multi-vitamin. Caffeine is also useful as a pre-workout boost, although a strong cup of coffee will do a similar job.

That’s not to say there are no other supplements worth using. But those are the main ones I take myself and recommend to others.