The last 10 years have been an exciting time in the exercise science world and especially in the area of bodybuilding and muscle building (hypertrophy) science.

There have been so many discoveries – even major breakthroughs – that there has never been more certainty about how to train to build muscle than today. That is, if you’ve been following the science. If you pay no attention to science, you might still be using training ideas that were outdated decades ago.

Muscle Building Science

I know that reading research papers is not high on the list of fun activities for most people. But others (me!) love it and are happy to study the literature, then simplify, summarize and share it.

Today, I want to share a summary of what I believe are the most important of the recent muscle building science breakthroughs. I’ll leave out the technical details and boil them down into simple, practical guidelines that help you create training plans that virtually guarantee your gains.

More good news: An over-arching theme we’ve seen in nearly all of these new studies on muscle growth is that there are few black and white rules and no single best way to do it. You’ve got room to choose and customize.

I know many people would like a coach to tell them exactly what to do – to just hand them a workout (or a meal plan). But the best way to design muscle building programs is to be a student first and learn the scientific principles of program design.

Then either create the muscle building program yourself from scratch, choose a stock program and customize it however you see fit, or have a coach design a routine for you, but with your input so it’s tailored for your goals, time available, and personal preferences. This way you always have a hand in the process.

Weight training programs, like nutrition, must be both scientific and customized. We now know that there is no single best lifting routine and that programs can be customized to a huge degree and remain highly effective.

For example, if a trainer says you must train heavy with low reps all the time to gain muscle, the science today clearly says they’re mistaken. In fact, without further ado, understanding the science behind low, medium and high rep training is a perfect place to start:

1. You can build a similar amount of muscle with almost any rep range if you train intensely enough and properly equalize for volume

Traditionally, doing heavy sets of 3 to 6 (low reps) has been considered ideal for strength, 8 to 12 (moderate reps) ideal for hypertrophy, and 13 to 20 (high reps) ideal for muscle endurance.

Research and simple observation have confirmed that heavy, low rep training increases absolute strength more. But new studies show that you can build similar amounts of muscle in the low, medium or high rep range as long as the volume is equal, and you train intensely enough.

What does intense- (hard) training mean? Usually, it’s leaving only a rep or two in the tank (training close to failure), or occasionally training to failure when it’s safe to do so and you can recover.

This means that there’s no single, narrow hypertrophy- zone for reps. Any rep range can build muscle if these two conditions are met (the right volume and intensity).

It’s not wrong to say the classic 8 to 12 rep range for hypertrophy is a good one. But when looking at the science, and factoring in practical concerns, anywhere from 6 to 20 reps will work great for building muscle.

See a complete analysis of the study proving how low, medium, and high reps all build muscle (members only)

2. You can build muscle with very light weights

It surprises many people that training with 15 to 20 reps, which is usually considered light weights- can build muscle.

It blows their minds when they hear that research says you can build muscle with very light weights and even higher reps in the 25 to 35 range. That equates to only about 30% of your 1 rep max!

Previously, lifters believed that going above 20 reps and especially 30 plus, would not build muscle size, it would only build muscle endurance. However, a study by Schoenfeld and colleagues showed that subjects gained muscle with sets of 25 to 35 reps as long as they did one thing: they pushed each set to complete failure or very close to it.

This is good news for people who don’t like to train heavy or simply can’t train heavy due to injury. When it comes to very high reps though, there are downsides.

As you would expect, training with very light weights is not effective for building maximal strength. In addition, very high rep sets are not time efficient. Obviously, a set of 30 will take 3 times longer than a set of 10 if the rep speed is the same.

Also, training to failure in the 20 to 35 rep range is fatiguing and burns like crazy. Some people can’t tolerate it. If you stop far short of failure on very high rep training, you simply don’t get the muscle building stimulus. This is why high rep training (13 to 20 reps) is probably superior to very high rep training.

It’s not optimal to do only very high reps. However, scientists hypothesize that very high rep training stimulates more growth in the slow twitch (type 1) muscle fibers. Therefore, a combination of low, moderate, high and very high reps might be ideal for optimizing growth in all muscle fibers (focusing mainly on the 6 to 20 rep range).

Even if you usually respond best with lower and medium reps, adding a high rep or very high rep set will probably enhance your muscle gains (examples: A. Three moderate or heavy sets and one high rep pump set.- B. One compound exercise with all sets heavy, then one machine or isolation exercise with high reps).

See full analysis of the original study on very high reps and muscle growth (members only)

3. You can virtually guarantee muscle gains and keep making progress for years by tracking one muscle building number (volume load / tonnage)

Many people use their journal (written or electronic/app) to record the sets, reps and weight lifted on each exercise. With these three numbers alone, you can track your progression. Progressive overload is literally the master key that unlocks muscle growth – it’s the holy grail of gaining muscle.

If your form was consistent, and you increased the weight for the same reps, you know you overloaded. If you increased the reps at the same weight, you also know you overloaded. If you added another set or exercise, you know you overloaded. Even if you do a drop set or rest pause set that you didn’t the week before, you overloaded. That means gains!

Some people think of progressive overload only as adding weight. But that’s a misconception. Increasing the weight over time is called progressive resistance. Progressive overload includes any increase in your total volume load.

Total volume load = weight x reps x sets, not just weight alone.

Volume load is expressed as the total pounds you lifted during a set, an exercise, or an entire workout. On exercises where you can lift heavy, the total can add up into the tens of thousands of pounds (tons), which is where the term tonnage came from. (Tonnage and volume load are the same thing; volume load is the more modern term).

Here’s a simple example:

3 sets X 10 reps X 100 pounds = 3000 pounds for the exercise
X 3 exercises at same reps and weight = 9000 pounds for the body part
X 3 exercises at same sets, reps and weight = 27,000 pounds for the workout

If your volume of work increases over time, you know you achieved progressive overload and you can expect to gain more muscle, as long as each set was a hard effort (in close enough proximity to failure), and all the other supporting factors (such as nutrition and recovery) are in place.

Even better, especially when your joints are aching, when you understand this math, you realize that you can make muscle gains without increasing weight.

Tracking tonnage / volume load in your training journal takes a little extra work, unless you have an app doing the math for you, but it may be worth it, because it reveals more than just the weight, reps and sets alone.

Learn more about tonnage (volume load)

4. You can optimize your muscle growth by counting your weekly sets and making sure you hit certain benchmarks

Research has shown that there’s a strong relationship between resistance training volume and muscle growth. More volume builds more muscle, but only to a point. Doing too much leads to overtraining and ultimately, you even go backwards (the volume-muscle growth relationship is a U-shaped curve).

The standard way to track volume is with volume load, which is sets X reps X weight in pounds or kilos (aka tonnage). But counting sets (“hard” work sets) has been proposed as an additional or alternative method of tracking volume that’s simpler.

A recent meta-analysis analyzed 14 studies and concluded that tracking sets can indeed be used to quantify volume and predict muscle gains as long as a few conditions are met.

First, it’s well-established now that between 10 and 20 hard work sets per body part per week is ideal for muscle gains. Make an important note: you can make gains with less than 10 sets. But current science says that 10 sets per body part per week is the minimum if you want to optimize.

Second, you can gain muscle training in a variety of rep ranges. To produce similar muscle growth, the reps should be at least 6 and ideally not more than 20. It’s possible to make gains in the 20 to 35 rep range, but it’s not ideal or practical. You can also make muscle gains in the 1 to 5 rep range, but this is also not practical when your goal is hypertrophy, not powerlifting.

Third, the sets should be taken close to failure (1 to 3 reps in reserve). They must be hard / intense efforts (warm up sets don’t count).

The bottom line is that the number of weekly sets you do per muscle group is an excellent metric to count both for knowing that you’re hitting optimal benchmarks and for tracking progression.

See full analysis of the new study on counting sets for increasing muscle growth (members only)

5. You can build muscle without training to failure, but knowing when to train to failure could help maximize your gains

The science is clear on this today: training to failure is not mandatory for building muscle. Beginners especially can make excellent gains in muscle size without training to failure or even having to train really close to failure. But as you gain training experience, it gets more important to make sure your intensity of effort is high enough. Going all-out on some sets may boost your gains from good to optimal.

However, training to failure must be done judiciously. Studies show that pushing all out to failure (where you can’t do another rep with good form) causes more muscle damage, increases recovery time, and may increase fatigue during a workout so that your performance in the back end of your training session may suffer (your volume load may go down because you blasted too hard, too much and or too soon).

Emerging research suggests that it might be ideal to save the all-out failure training for the last set of each exercise. In addition, you should use caution when going to failure on compound, multi-joint exercises both for fatigue management and safety reasons.

Failure training is safer and less likely to lead to overtraining when it’s done on machines and single-joint exercises. Older lifters should be even more cautious when using failure training both for safety and recovery reasons.

Periodizing failure training (using it in cycles) may be a good option, where you would stop short of failure in one training phase, then during a peaking phase that follows, kick up the intensity level. When you start to feel the accumulated fatigue and need for recovery, you back off the intensity, then repeat these cycles.

When muscle growth is the primary goal, following the guidelines above would be a smart move. But it’s also worth noting that if maximum strength is the goal, most research suggests that training to failure may not provide an advantage, yet it still increases demands for recovery.

When training for strength, stopping with a little bit left in the tank may provide the same strength gains without beating up the body so much. Make sure you adjust your strategy based on your goal — bodybuilding and powerlifting are not the same.

See the newest study on the effect of failure training on muscle damage and fatigue (members only)

6. You can train each muscle as little as one time a week or as often as three times a week and get similar muscle gains if you monitor and adjust your volume properly

Traditionally, bodybuilders gravitate to split routines where muscles are worked less often (only once every four to six days or even as infrequently as once a week. By contrast, strength athletes typically hit each muscle three times a week, often on full body workouts.

For years, many coaches and athletes argued that working each muscle only once a week was not ideal, even if your primary goal is bodybuilding. Some of the research did seem to confirm better muscle gains with a higher training frequency, at least working each muscle twice a week. It was hypothesized that this was due to stimulating muscle protein synthesis more often and promoting greater neural benefits that support strength gains.

The problem was most of this research didn’t match the volume for a fair comparison. In studies where weekly volume is matched, there’s usually minimal difference in muscle growth or strength regardless of whether a split or total body routine is used.

Some research suggests that if you want to do a lot more than 10 sets per body part per week, then it makes sense to spread it out across the week with a higher frequency rather than blast a body part in one session a week for 15 to 20 sets (which would produce major muscle damage and fatigue that could take many days to recover from).

Ultimately however, if the weekly volume is equated, the muscle growth results should be similar, whether you work each muscle once a week, twice a week or three times a week.

Should you train each muscle once a week or twice a week: A closer look at what the science says

7. You can train on a full body workout or break up your exercises into body part split routines and get similar muscle gains if you monitor and adjust your volume properly

Some studies suggest that split routines are ideal for muscular size and total body training is ideal for strength. But there’s been a big debate about whether split routines are better than full body routines. Just like the debate over training frequency, the problem here was the same – most of the initial research on the topic didn’t match for weekly volume (tonnage or how many sets).

In the newer studies where volume for the week is matched, there is usually minimal difference in muscle growth or strength regardless of whether a split or total body routine is used.

A new study published in the Journal of Strength And Conditioning Research compared the effects of a 4-day bodybuilding-style split to a total body routine on strength and muscle growth. Both routines were matched for volume.

The overall finding was that in experienced, trained male lifters, age 18 to 35, after 10 weeks, both programs had increased the subject’s muscle mass and maximal strength when volume was equated.

The gains were similar between groups. Neither split routines nor total body training stood head and shoulders above the other. However, total body training did appear to have a slight edge for building maximum strength, while body part split training may be more conducive to building muscle size.

See full analysis of the latest full body training vs split routines study (members only)

8. You can achieve better overall muscle development by using a variety of exercises and changing them regularly, while at the same time consistently using basic compound exercises

When your goal is bodybuilding or gaining muscle size (hypertrophy), science confirms the popular belief that workout programs should include a variety of exercises that work every muscle from different angles and through different planes. This helps assure that every section of every muscle is developed completely, and it may help prevent pattern overload overuse injuries.

The programs should also use a combination of multi-joint compound exercises and single-joint isolation exercises to ensure total muscle development.

A good example is including the leg extension in addition to the squat. If you could only do one exercise, there’s no doubt the squat is superior. But doing both the squat and leg extension provides greater development of the entire quadricep group because leg extensions activate the rectus femoris more than the squat alone.

You should change exercises periodically, but it’s important to stick with basic compound movements for extended periods to allow for progressive overload and improve motor skills. As long as you include basic exercises, isolation and machine exercises can be rotated more often for variety.

You should choose your exercises intelligently so that every section of each multifaceted muscle is fully trained, and weak points are given attention, rather than choose and switch exercises randomly for the sake of variety.

The idea that you should use muscle confusion – and change exercises constantly can work against you because this doesn’t allow continuity and progressive overload. On the other hand, your body will adapt and plateau if you stay on the same exercises all the time.


There are a quite a few more muscle building science breakthroughs I could list, but this covers all the most important bases: reps, sets, volume, frequency, intensity, exercise selection, splits and progressive overload. Check off all these boxes, based on the current science, and I’ll say it again: You are virtually guaranteed to make gains.

Train hard and expect success,

Tom Venuto,
Author of Burn the Fat, Feed the Muscle
Founder of Burn the Fat Inner Circle
Not an Inner Circle member yet? CLICK HERE for Inner Circle membership info

PS. Are you wanting to gain muscle, but you have limited time? If so, be sure to take a look at the antagonist superset training method. It’s the system we use in “The New Body TURBO” program, and it can reduce your training time b y 30% to 50% (yes, you can legitimately cut your workout time in half) without compromising on muscle strength or muscle size. Click Here To Read About How This Training System Works.

tomvenuto-blogAbout Tom Venuto, The No-BS Fat Loss Coach
Tom Venuto is a natural bodybuilding and fat loss expert. He is also a recipe creator specializing in fat-burning, muscle-building cooking. Tom is a former competitive bodybuilder and today works as a full-time fitness coach, writer, blogger, and author. In his spare time, he is an avid outdoor enthusiast and backpacker. His book, Burn The Fat, Feed The Muscle is an international bestseller, first as an ebook and now as a hardcover and audiobook. The Body Fat Solution, Tom’s book about emotional eating and long-term weight maintenance, was an Oprah Magazine and Men’s Fitness Magazine pick. Tom is also the founder of Burn The Fat Inner Circle – a fitness support community with over 52,000 members worldwide since 2006. Click here for membership details


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