Should You Train To Failure To Build Muscle? - (Science Overview)

Is training to failure necessary for muscle growth?
The quick answer is no, but this only makes things even more complicated than they are. And I say this because if training to failure is not necessary to build muscle, then what is the ideal intensity of effort that one should have to see noticeable results in muscle growth?
To answer this question we need to understand what we really compare in this debate. You see most people compare failure training with just any type of non-failure training. However, a "non-failure set" can be anywhere from 10 to 99% of the repetitions done in a failure set. To make things simple, if you do 16 reps on a failure set, a non-failure set on the same intensity can be anything between the range of 1 to 15 reps. So comparing failure sets with non-failure sets, in general, doesn't help a lot. The only accurate comparison between the two practices is when we specify how many repetitions before failure, did the non-failure group/set stopped. This can be done through a scale called Reps In Reserve (RIR). In this scale, an RIR of 0 equates to training to failure, an RIR of 1 equates to stopping 1 repetition before failure, an RIR of 2 equates to stopping 2 repetitions short of failure, and so on.
The actual question that we should be asking then is "should we train to failure for muscle growth or should we train with one or more Reps In Reserve (RIR)?"
And the answers here are pretty simple. The evidence that we have today indicates that training all the way to failure is more effective for muscle growth than training with 6 to 3 RIR. So should you train to failure on every set? Well... no. You see, when failure training was compared with non-failure of 3-1 RIR most of the studies found no differences between the two, and one found that the non-failure group had significantly better results in building muscle. It seems then that when you get close to failure, between 3 to 1 reps, but not all the way to failure, is the most effective practice when trying to build muscle. Most of the authors of the studies presented in this video believe that this comes mainly from the effect that failure training has on recovery time. Training close to failure will definitely increase your recovery time and make you perform worse in the following training sessions.
However, specifically for muscle growth, training to failure occasionally is necessary at least for one reason.
And this comes from our inability to accurately estimate how many repetitions are left to failure on each set. What this means is that most of us that will try to train with 1 or 2 RIR, will probably train with 4 or more RIR. This is the same for both trained and untrained individuals as was shown by a 2017 study by Hackett and co-workers. In this study, authors reported that participants couldn’t correctly estimate their repetitions to failure regardless of their training level. In their conclusion, they pointed out that “the majority of sets should be performed close to failure, with failure sets used sparingly”.
So this is where the need for failure sets comes handy.
You can use failure sets at the last set of an exercise to test if you are truly training at the intensity you want.
However, you shouldn't do failure sets at the end of each session. And that's because this is similar to what Carroll and colleagues did in 2019 on their failure protocol and remember that they found the non-failure groups to have more gains. So using failure sets as a daily practice is probably not a good idea and is probably better to use it sparingly, to test if you’re on the right track.
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Contents of the video:
00:00 - Intro
00:27 - Studies Comparing Failure with 6-3 RIR
00:49 - What is RIR?
01:22 - Failure takes second place...
01:54 - Studies comparing Failure with 3-1 RIR
02:47 - The 4 cons of failure training
04:32 - And the winner is...
05:22 - Why you should STILL train to failure... occasionally
06:36 - Why not do a failure set at the end of each exercise?
07:07 - The two most popular arguments in favor of failure training
08:19 - What is the optimal rep range for muscle gains?
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References:
pubmed.ncbi.nlm.nih.gov/26049...
pubmed.ncbi.nlm.nih.gov/28713...
pubmed.ncbi.nlm.nih.gov/15947...
pubmed.ncbi.nlm.nih.gov/16794...
link.springer.com/article/10....
pubmed.ncbi.nlm.nih.gov/28965...
pubmed.ncbi.nlm.nih.gov/27787...
pubmed.ncbi.nlm.nih.gov/31365...
pubmed.ncbi.nlm.nih.gov/31809...
pubmed.ncbi.nlm.nih.gov/29628...
pubmed.ncbi.nlm.nih.gov/25809...
pubmed.ncbi.nlm.nih.gov/25809...
pubmed.ncbi.nlm.nih.gov/29189...
pubmed.ncbi.nlm.nih.gov/31373...

[@YiannisChristoulas]

I hope you enjoyed this video! Don't forget to hit this link for more: bit.ly/3SIwH4o

[@agzfd]

Yours is such a good content. This is what informational videos should be like, regardless of the topic

[@YiannisChristoulas]

Thank you sooooo so much! 😁

[@kingadjust6201]

​@@YiannisChristoulas I saw a study that people who have trained less than 6 months got 4% more results going to failure and people who have trained longer got 2-3% better results by training 2 reps in reserve what do you think? Since I'm newer to working out and don't get sore is failure training better for now? 😎👍

[@malamateniaanag6291]

Thanks for the useful fitness information and explaining everything so well. Cant wait to see the next video!

[@YiannisChristoulas]

😁

[@connorjensen9699]

this is an incredibly well put together resource! Thank you! I love that you also made whole T shirts for each haha so great

[@YiannisChristoulas]

Hahaha yeah the T-shirts were fun, it was a last minute idea 😃 I’m glad you liked the video!

[@Yojax]

Amazing quality as usual. Thanks for sharing this info and investing the time to make a very well edited video.

[@YiannisChristoulas]

Thank man! I appreciate it a lot! 😎

[@agufana]

Appreciate all the effort you go to in the video. Thankyou for sharing.

[@YiannisChristoulas]

Thank you! 😃

[@hsscha]

top notch content as always, thanks for these videos, they are always amazing

[@YiannisChristoulas]

Thanks man I appreciate your support 😁

[@user-ke6zc6kl9w]

Excellent work!! can't wait to see the next video!

[@YiannisChristoulas]

😁

[@crumdub12]

Excellent video Yiannis , they are the best research to analytical training on YT

[@YiannisChristoulas]

Thank you I’m glad you found it helpful 🙂

[@GeorgeDoc250]

In addition to everything else, the production vales keeps going up, well done sir!

[@YiannisChristoulas]

Thanks George! I’m glad you noticed this, I’ve been investing a lot on this lately 😎

[@danien8222]

Thanks Yiannis. Amazing analysis of this research. There's so much confusion re training to failure for gains. I would be interested in what the research says re training to failure and relative risk of injury. - This would be helpful for hobbyists rather than pro athletes, to weigh up the pros and cons of doing this.

[@YiannisChristoulas]

Thanks Dani! It’s hard to find research related to risk of injuries in general. However the risk of overtraining and increased time for recovery are easier to predict. In general when you don’t need something you simply don’t do it. So if there’s no reason to train to failure, just don’t

[@doopdoop16]

Thanks dude. Always helpful and insightful

[@YiannisChristoulas]

Thanks man I appreciate it!

[@Shizo_san]

Such an amazing video as always, thank you

[@YiannisChristoulas]

Thanks friend! I see you haven’t missed any of my videos 💪😁

[@AV1461]

Thanks for the video! This is some serious content. Very good. It would also be cool to look into the basics of nutrition for hypertrophy. I have many questions there too.

[@jrg305]

I don't think that part is super complicated. Make sure you're eating maintenance or surplus calories, and 1.4-2.0 g protein/kg bodyweight. You can also have a read of the ISSN paper on diets and body composition and the Helms et Al macronutients for body building paper. Short version is it isn't much different from the generally accepted macronutient guidelines (AMDRs). ISSN doesn't think the macronutient comp matters though, but ACSM does if you're doing a lot of aerobic exercise, then they really focus on grams/kg Carbohydrate based on duration of aerobic exercise. Yiannis does excellent research analysis of these exercise science topics, and it is harder to stay up on it since I don't know of a major organization that shoves it in our faces as fitness professionals whereas there is a whole organization of dietitians who do have to take Board certifications and show hours of experience to keep up with the science like the RD, CSSD credentials. Fitness certifications don't do that very well.

[@jrg305]

What is more complicated is knowing when your body is recovered and you're actually optimizing when the exercise stimulus should be. We can't always know what state of net protein anabolism or catabolism we are in real time. We are always in a state of recovery, super compensation, detraining, or inflammation after an exercise stimulus, and general health requires us to do a variety of exercise types and modes to hit different physiologic systems. Our energy expenditure isn't always uniform each day of the week, and devices that say they measure it aren't measuring our heat expenditure or thyroid activity, or how our activity changes or eating behavior changes after exercise (some of us just sit around more or lie down more than we otherwise would). Then there is the factor of being an adult and finding time to exercise when you can rather than when is optimal physiologically. Single college aged men to unmarried singles with flexible jobs vs men who work certain hours and have families.

[@YiannisChristoulas]

Thank you Arthur! Yes protein intake is definitely on the list as one of the next vids. For now I’d say that I agree with much of what @jrg305 commented here

[@jrg305]

Great video Yiannis! You're getting funny and fancy with the multiple versions of you on the medal ceremony platform 😂😁 I could tell you enjoyed that. I did, too.

[@YiannisChristoulas]

Thank you friend, I did enjoy this one and I’m glad you did too!

[@Yamshabass]

Great video! I would be interested to know if similar research has been done on going beyond failure (partial reps at end of set)

[@YiannisChristoulas]

Thanks! I’m not familiar with any, but it would indeed be interesting

[@el7ag10y]

Amazing video thanks

[@elenichouvarda8229]

Bravo Yianni. You are so geat in your videos. We really enjoy you.

[@YiannisChristoulas]

Thanks for the support Eleni!

[@christinamilioni6325]

Very comprehensive and accurate! Ευχαριστούμε.

[@YiannisChristoulas]

Thank you Christina!

[@johnnyk7132]

Το κανάλι σου είναι πάρα πολύ καλό και τρομερά backed by science, συγχαρητήρια keep it up!!!

[@YiannisChristoulas]

🙏

[@estergaleotenadal5870]

Really good video!

[@YiannisChristoulas]

Thanks!

[@snake1625b]

Great video, Jeff nippard 2.0 haha In regards to what you said at 7:02, that study tested failure for every set vs 1-3rir for every set (including the last). So wouldn't that not test the hypothesis that going to failure ONLY on the last set is best?

[@YiannisChristoulas]

Lol thanks! You mean the Carroll paper?

[@snake1625b]

@@YiannisChristoulas yes in the carroll paper, in the non failure group, they didn't take the last set to failure. In order to test if taking the last set to failure, there would need to be 3 groups: 1) failure for every set, 2) failure on ONLY the last set and 3) 1-3rir for every set. Then if group 2 shows the best results then we truly know that only taking the last set to failure is the best.

[@matiasneira9084]

when will you upload a video about the force?

[@bboyqbunia608]

Wow super great content.

[@YiannisChristoulas]

🙏

[@philippemousques5515]

Question... On minute 4:00 you said that if you train to failure (12 reps being your failure) and you do 12 reps on your first set, then your second set failure will be something around 10 reps, which makes sense, and after three sets your total will be around 30 reps. So far I agree. But on the second example, if we are talking about the same person, and their failure point is still 12 reps, wouldn't 10 reps be their amount of reps with 2 RIR? So 3 sets of 2 RIR (10 reps) would add up to 30 as well. Hopefully my explanation makes sense.

[@YiannisChristoulas]

On the second example the failure point is 14 reps, because it’s 12 reps with 2RIR. I made it this way so you’d have the same potential for training volume. I should probably explain this with a bit more detail. Makes more sense now?

[@kurtkrienke2956]

@@YiannisChristoulas I got stuck on this as well. If you are assuming a more endurant trainee in the second example, you are making your point obsolete if the point is that not training to failure leads to more reps over the course of multiple sets.

[@YiannisChristoulas]

@@kurtkrienke2956 if your goal is to have a training volume of 36 reps, you can either try 12 reps to failure or (with a lighter weight) 12 reps with 2RIR. On the second example you’ll achieve the 36 reps but not in the first one

[@kurtkrienke2956]

@@YiannisChristoulas That is true, but it comes at the expense of tonnage. This is unavoidable in this circumstance, only I understood your example (as I believe others did as well) in a way where the only variable is intra-set volume. If the load is varied as well, you have inherently less comparable situations.

[@thomatofpv3546]

Before reading my comment I would like to preface by saying that your video is of excellent quality and really helpful for beginning trainees, but I would like to add some points that are more focussed on intermediate to advanced lifters in the gym. In my opinion, you need to train to failure if you want to go beyond being intermediate in the gym. The problem with the studies mentioned is that they use lightly trained and sometimes even untrained individuals which will grow with anything. Another thing is that people often estimate RIR or RPE wrong, making them have 6 RIR when they think they have 3 for example. On some exercises it of course does not make sense to train to failure every set such as squat, deadlift, bench (compound movements). But some other exercises like lateral raises, bicep curls, calf extensions (accessory movements) can and should be taken to failure and even beyond (partials/ slight cheating at the end) to see some significant results. If you do this is a normal amount (not swinging your pants off) there is not really an increased risk of injury. The recovery part is obviously important to keep in mind, but as you get further in your lifting career most people should be able to recover just fine from taking the smaller muscle groups to failure no problem. There is no such thing as a BIG natural lifter that does not train to failure.

[@YiannisChristoulas]

Thanks for the detailed comment! What is your opinion on the Caroll study from 2019, that had experience lifted with average around 8 years of consistent resistance training? They found the non-failure group to have significantly higher results in muscle growth.

[@thomatofpv3546]

@@YiannisChristoulas I think it is a very interesting study, I read through the paper and must say that it looks well executed. The only thing that comes to mind for me is that they take everything to failure all the time with movements such as back squat and bench press, which will obviously do play a role in your recovery and being able to perform in your next workout (Try 3 sets to true failure on squats with 8-12 reps as they mentioned and then do the same on bench later that day??). As mentioned before I believe the failure training should mostly be left for the accessory movements and not the compound lifts of the day because of asymmetric benefits (more risk of injury, higher recovery time). I think this study mostly shows that if you train super hard and go to failure on every set for no real reason it will indeed cost you gains, but this is nothing new. But maybe I just don't get it and I am looking for confirmation bias to continue slamming sets to failure on bicep curls, tricep extensions and lateral raises haha!

[@YiannisChristoulas]

@@thomatofpv3546 hahaha I don’t know maybe you do, but it seems that you are open minded and willing to study on the topic. In this study however they didn’t do failure in every set. On the failure condition they only did a failure set at the last set of each exercise. This is one of the reasons the results are so important. I totally agree that if failure is uses it should be practiced only in isolated accessory exercises.

[@thomatofpv3546]

@@YiannisChristoulas you're right, can't believe I read over that the first time. To me the information sounds compelling and worth to at least try out for myself.

[@YiannisChristoulas]

@@thomatofpv3546 and a personal note, to be honest I don’t think that going to full failure, let’s say 12 reps on the biceps, instead of 11 will make much difference. But it will certainly reduce the reps of the following sets. Try it out. Wish you the best!

[@kuolewaft9623]

So you say 50 reps is better than 8 because its more volume? It is the reps that recuire all motor units and myofibrils to work that matter. Which are usually the last 5-6 reps of the set. So 8 and 12 reps are just as afficient.

[@frog6054]

Does this only applies to heavy compounds exercises? I only do bodyweight exercises like push ups and pull ups for hypertrophy (due to lack of access to gym) so does training 3-1 reps in reserve still applies to lighter exercises? And what about isolation exercises like bicep curls and tricep extension? Many people said it's optimal to go failure on them.

[@YiannisChristoulas]

It applies to all movements and especially to compound movements. What Carroll et al., 2019 did was do a failure set at the last set of each exercise. They compared this with a non-failure group around 3RIR. They found that the non-failure group had a lot better results in muscle growth. It was a big period of ten week with experienced lifters.

[@frog6054]

@@YiannisChristoulas So that's mean beyond failure like drop sets is not useful?

[@YiannisChristoulas]

@@frog6054 This means that if you are in a position to train close to failure, going all the way to failure or beyond it will most likely not add anything to your results. The hard reality is that to build muscle you need mostly consistency. Someone training with 6RIR for 10 years will have a lot greater physique than someone training with 2RIR (harder) for 5 years and then stops. However consistency is boring.

[@frog6054]

@@YiannisChristoulas I see. Thank you for sharing the information.

[@shakya00]

The problem is that it is hard to estimate how many RIR you have and failure is still better than the 3-6 RIR range. In a perfect world, it is better to go for 1-3 RIR as explained in the video but if you don't know your max rep, it is better to go to failure than having 3+ reps in reserve.

[@pqsnet]

By logic i recon this has to do with muscle fiber engagement and form wether you ae or are not experienced. If you work out to failure and have bad form, and thus not engaging your fibers in their full potential, its useless.

[@annakessler9372]

good video. But these studies are not always acurate and on point. The body itself can tell you the intensity of your training and if you had enough or not

[@SuperDrweb]

Hello. Please make a video about gaining muscle mass using only your own body weight.

[@YiannisChristoulas]

I’ll add it on the list ✌️

[@FenderAddict93]

At 4:13, it’s inaccurate for Yiannis to say that more volume can be performed by 2 RIR. As what I understand of RIR, it is the number of reps you can still push out UNTIL failure but instead choose to hold those reps back. So in his FAILURE example at 4:13, the reps to failure is 12 and 2RIR is also 12. This is WRONG cause if 12 is the max reps to failure, then 2RIR should’ve been 10 instead which actually evens out the totals for both types of training ie. 30 reps in total each. Am I missing something here?

[@YiannisChristoulas]

The second option is supposed to be the same 12 reps with less weight, thus with 2RIR. In the first option you take the weight that takes you to failure at 12 reps. So for example 9kg on the first and 8kg on the second option, would result in 12reps 0RIR and 12reps 2RIR respectively

[@someman7]

If you do 12, 10, 8 to failure, how can you have 2 in reserve doing 12, 12, 12 (at 4:12 mark)? You would do 10,10,10, wouldn't you ? And that adds up to the same number, 30.

[@YiannisChristoulas]

The first number is 12 to failure the second is 12 with two RIR. So less weight one the second one.

[@someman7]

@@YiannisChristoulas Oh... But then the total should reflect the weight as well. But sure I guess..

[@YiannisChristoulas]

@@someman7 yes it could be done other way too. On this example I assume that we want a particular number of reps achieved

[@cydu]

If you want strength without muscle mass, is training to failure better?

[@YiannisChristoulas]

Training many repetitions from failure (>5) is better for less hypertrophy gains. Also train with high velocities (and only until you can stay fast) or with load that lets you do between 5 to 1 repetitions, will increase mostly strength with less hypertrophy gains

[@cydu]

@@YiannisChristoulas Thanks, so I should do many repetition, or heavy load less than 5 reps.

[@YiannisChristoulas]

@@cyduSome of your options are the following: 1) Train with many repetition from failure. If 16 reps is when you reach failure, do only 10 or 11 2) Train with high speed in each movement and finish the set when you start getting slow 3) Train with loads high enough that you can only do from 1 to 5 reps. On this rep range you get less effects on hypertrophy if you don't do many sets. 4 Set for example would probably be fine for your goal. 🙂

[@cydu]

@@YiannisChristoulas thanks so much!!

[@vijayendranvijay457]

What about for muscular endurance?

[@YiannisChristoulas]

Muscular endurance (strength endurance) is predominantly based on volume. Failure reduces volume. 😎

[@vijayendranvijay457]

@@YiannisChristoulas That makes sense. However, I found a 2006 study titled "Differential effects of strength training leading to failure versus not to failure on hormonal responses, strength, and muscle power gains" which saw an increase in muscular endurance for bench press in elite Basque Pelota athletes although no increase in squat when doing sets to failure.

[@forgottenstrengthsecrets]

HUGE DIFFERENCE BETWEEN 2 OR 3 RIR AND 6

[@YiannisChristoulas]

👌

[@morph1232]

Just waiting for the first rage comment about junk volume 🤷🏻‍♂️😅

[@YiannisChristoulas]

😂

[@noelchoh3744]

Ummmm how many people actually know how may RIR they have. This is just plain silly.

[@YiannisChristoulas]

If you do a failure testing and then for the next two or three weeks train with 1-3 reps less, then you know you’re on the correct range. That’s also because if you try to do 4sets with 3RIR, on the forth set you are very close to failure. If this doesn’t happen then you know you should adjust the weight accordingly. So training with 3 or Less RIR gives you instant feedback from your last sets. Even more as was shown by Hackett and co-workers the closer you get to failure the more accurate you get at estimating your RIR. So estimating 1-3RIR is a lot easier than estimating 3-6RIR.

[@Toalen]

4:16 You chose a bad example. Maybe say 11-11-11 and show 33>30, but otherwise what you showed proved nothing great video otherwise

[@YiannisChristoulas]

Isn't 36 a lot greater than 30?

[@kurtkrienke2956]

@@YiannisChristoulas it is, but it is achieved by a trainee who's failure occurs at 14 reps as opposed to the trainee failing at 12 reps in the first example.

[@YiannisChristoulas]

@@kurtkrienke2956 I think you’re missing something here

[@loganosmolinski4446]

Boop