Do you need to lift heavy to build muscle?
Do you need to lift heavy weights to build muscle?
The short answer?
No. You don’t have to lift crazy heavy weights to build muscle mass.
1. Train with five to 30 reps per set.
2. Take every set to muscular failure.
What we mean by “heavy”
Let’s say you’ve only been lifting a few weeks.
You might be working out next to someone who’s been going to the gym for 10 years.
They might be warming up with weights you’d find impossible to lift.
What’s “heavy” is personal.
So lifters like to discuss weight selection in terms of a percentage of your one repetition maximum (one rep max, or 1RM). That is, the most weight you can lift for a single rep.
This value isn’t static, though.
As you keep training and getting stronger, your 1RM will increase. Your old 1RM will become your three rep max, then five, then 10.
How useful are 1RM percentages for hypertrophy?
However, determining your true one rep max for certain exercises is difficult.
If you’re new to training, you might not feel comfortable taking your body to the edge. To have to do that before you can start selecting sensible weights? A tall order.
A more practical approach when your goal is to build muscle is… to simply pick up a weight at random and do a set with it.
That’s right.
Surely not..?
While this might not sound precise or scientific, this is exactly what I do when I incorporate a new exercise into my program.
I select a weight more or less at random, and start moving it.
Trial and error is okay. Within a session or two, you'll be using the perfect weight for you.
Instant feedback...
That's because you’ll get instant feedback on how appropriate the weight you've selected is.
If the weight flies through the air, it’s too light. If you struggle immediately, it’s probably too heavy.
If you hit 10 reps and are barely breaking a sweat, put the weight down and select something heavier.
If you hit muscular failure in under five reps, choose a lighter weight next time to put yourself in the 5-10 rep range.
If you went too heavy and the exercise felt slightly unstable, or aggravated an injury, choose an even lighter weight that puts you in the 10-15 rep range. Or, go lighter still, and work in the 15-20 or 20-30 rep range.
What do I need to do to build muscle?
Earlier, we said these two things are necessities for muscle growth:
- Train with five to 30 reps per set.
- Take every set to muscular failure.
These deserve a bit more attention.
First, let’s define muscular failure.
What is muscular failure?
A GQ article on this topic calls muscular failure, “The point where you feel like you can’t keep going any longer.”
This is wrong.
Muscular failure is not “where you feel like” you can’t do another rep. It’s where you actually cannot complete another rep.
This means you always attempt another rep. You give your absolute, gut-wrenching best… But you can’t move the weight.
This is not a small point.
Lots of beginners have no idea where muscular failure truly is.
Many end the set as soon as it feels hard.
Wrong.
Others end the set once the weight starts to slow down.
This, too, is wrong.
In fact, the reps where you experience an involuntary slowing of the contraction is where something called mechanical tension is at its highest. And it’s this exact process that triggers muscle protein synthesis and new muscle growth.
So, if you stop when the set gets hard, or once your reps start to slow, you’re effectively minimising the muscle-building stimulus.
Try this to never wonder what muscular failure is again...
You can try this right now.
Get on the floor, and do a set of push ups. Aim for 100 with good form. Touch your nose to the floor at the bottom, and fully extend your arms at the top. Do 100 of those.
You won’t hit 100, but really try.
Don’t stop when your arms get tired. Don’t stop when it gets uncomfortable. Keep going.
Keep going...
You might get 30. You might get 50.
The number doesn’t matter. What matters is that you feel:
- Your reps start to slow down (involuntarily) as you near muscular failure.
- You reach the point where you attempt another rep, you’re contorting your face with the effort, you think you won’t get it… but then you do.
- …And then you go for yet another rep.
Always attempt another rep...
You might get this one too, but eventually you will fail to complete the rep, and you’ll collapse onto the floor.
You’ll probably have to roll onto your back and roll around like a beetle to get back up.
But… congratulations! You’ve experienced muscular failure!
Engrain that feeling in your head and chase it when you’re next in the gym.
5-30 reps for muscle growth
So… why not just use push ups to grow your chest and arms?
Well, you can… for a while.
But eventually, the stimulus to fatigue ratio becomes unfavourable.
Stimulus to fatigue ratio
What ends up happening is that, to hit muscular failure, you end up having to perform 50-100 reps.
This is an issue.
See, researchers found that muscle growth observed in test subjects was largely the same no matter whether they did sets of about 5 reps, or sets of about 30 with lighter weight.[1]
Do this to maximize the muscle building stimulus
It takes about 5 reps in a single set taken to failure to maximise the muscle building stimulus.
Any lower than that, and the adaptations become more neural than muscular.
Much higher, and you generate too much central fatigue relative to the muscle-building stimulus. In other words, you’re working out inefficiently.
So… are sets of five reps and sets of 30 reps equally optimal for building muscle?
They’re not. That’s because of:
- Injury risk.
- Psychological stress.
Injury risk
If you have an injury, or your joints don’t like certain exercises, lighter weights will be less risky, and you can still get just as good a muscle-building stimulus.
For example, my left shoulder feels awful during most fly-type chest exercises. I have to be careful, and make sure my joints are thoroughly warmed up.
This doesn’t mean I don’t “lift heavy”. Compared to some, I’ll still be moving a lot of weight. But I prefer to stick to the 12-15 rep range and higher. This way, I’m not stressing my joints pushing heavy weights I can only move for five reps.
Why lighter weights are better if you have injuries
When you train heavier, it’s not just your muscles that are exposed to those heavier loads. Your tendons and soft tissue have to take the load, too.
In most cases, this is a good thing. Weight training increases the tensile strength of your tendons and ligaments, and increases bone density. Training properly when you don’t have existing injuries that already present a problem can make you far more resistant to injury.
But when you’ve got existing injuries, it’s wiser to be cautious.
Psychological stress
Some exercises are much more difficult than others.
Once you become moderately strong, knowing how taxing it’ll be to perform that exercise can be mentally stressful.
This has happened to me in the past. A leg session with too many taxing movements actually causes me to lose sleep the night before. I’ll feel anxious all day in the lead up to the training session.
In many ways, this makes sense. Get strong enough, and you’ll be moving weights many times greater than your body weight. There is, inherently, some risk involved.
Your brain is smart enough to know you’ve got a big challenge coming up. It’ll do its best to prepare you for the threat you’re about to face.
Why this is a problem for busy professionals
For busy professionals with a lot on their plate, though, this is a problem.
If you’re a busy professional working 60+ hours a week in your 40s, your training should not be an additional stressor. It’s counterproductive.
It’s actually far better for you to leave your training sessions feeling like you could have done more.
Aim for sessions that feel like this...
This way, on your worst weeks, when your kids aren’t letting you sleep, and you’re struggling to get your team to hit their targets, your sessions still seem manageable enough that you’re not at risk of falling off-plan.
So here’s what to do…
A 30-rep set of heavy leg presses or hack squats to failure will be absolute torture. An 8 rep set, while still difficult, won’t seem nearly as scary in the lead up to the training session.
That means less stress, better recovery, and actually a stronger net muscle building stimulus.
Conclusion: Can you build muscle without going heavy?
So… If you’re wondering whether you can build muscle without going heavy, the answer is yes.
Though "heavy" is relative, what's most important is that you stay within a reasonable rep range, and that you train to muscular failure (or very close to it) on each set.
FAQs:
Do you need to lift heavy weights to gain muscle?
- No. As long as you perform sets of between five and 30 reps, and take every set to muscular failure, you’ll experience roughly the same muscle building stimulus from each set.
Should I lift heavy or light to gain muscle?
- Both heavy and light weights can be effective for muscle building. Choose a weight that feels comfortable on your joints, and perform a set to muscular failure.
Can you build muscle without going heavy?
- Yes, you can build muscle without lifting weights that constitute a very higher percentage of your one rep max. But you still need to take those sets to muscular failure to maximise their muscle building stimulus.
Is it OK to not lift heavy?
- It’s okay not to lift heavy in the gym if you don’t want to. If you’re concerned about injuries, or find heavier weights more psychologically stressful, you can still build muscle with lower weights and higher rep sets. You still need to keep the intensity high, though, and train to, or just shy of, muscular failure.
References
[1] Beardsley, Chris. Hypertrophy: Muscle fiber growth caused by mechanical tension (pp. 203-204). Strength and Conditioning Research Limited. Kindle Edition.