This post is inspired by an answer that got voted up a lot over on Quora.
The answer, like so many (Shocking right?) of mine over there is…
Let’s dive into this a little bit:
First I want my readers to know that muscle breakdown and consequent rebuilding is a constantly occurring thing.
It is also breaking down things like triglycerides into fatty acids, and things like glycogen into glucose and back again sometimes, but let’s keep this discussion focused on protein.
Lifting weights is not the only thing that will ’cause’ muscle breakdown, the stimulus just has to be above the threshold of tolerance your muscles have currently.
Things like lack of sleep, disstress, eustress, the fight or flight response, nutrition, etc… can and will all affect how metabolic muscle tissue reacts to it’s environment.
Many people believe that soreness = results and that lifting to failure = soreness, so if they want to gain lean muscle mass, they will lean towards trying to create soreness.
And before I continue if you’re aim to lose weight, you should aim to displace some of the adipose (the politically correct way to say ‘fat’) with far more metabolically active lean muscle tissue, it will definitely keep you thinner for longer.
Back to soreness, the truth is that if all your doing right now is lifting weights and you went out for a sprinting session, not only would you get sore, you’d also get muscle breakdown.
What is really important for creating ‘soreness’ is change, so lifting to failure is not the only way to induce soreness and soreness does not always indicate muscle growth.
Basically, all you have to do is change an exercise slightly, change a rep or set sequence, change a tempo sequence, change the mechanical advantage, etc…etc… if you want to stimulate the muscle into a ‘different‘ kind of breakdown.
Remember to break down your training programs into 3-6 week chunks as a general rule if you want to maintain continued adaptation.
Second, bodybuilding has historically given people the notion that you should always train to failure, without really defining what failure actually is.
Lifting to failure can and will generally make you sore, and if you follow the above flawed logic, you will unfortunately feel endlessly sore.
The down side of this is that being continually sore can significantly impact your performance in the gym, it’s not exactly fun to lift when you are sore.
However, I have personally had some of my best quality workouts while still sore from previous workouts, so don’t use soreness to gauge your recovery either (it’s a bad indicator).
I just generally do not want my clients to be in physical anguish all the time and I don’t think you want to be either.
This is why body builders often break down their workouts into body part splits, so they can minimize training through soreness — a great idea in 1980 when we didn’t know as much about the human body maybe it was easy to assume that soreness meant you hadn’t recovered yet, but now we know better.
Body part splits for the vast majority of people is not only impractical, it’s not particularly useful if you only have 3 days a week to train.
Frequency in training is one of the most important variables if you’re just getting started with training, and lifting to failure will prevent you from hitting an ideal frequency or consistency in your training.
It’s been my experience working with a lot of busy people that full body or at most upper/lower split style routines are ideal even if bodybuilding is a distant objective.
Third, I’ve talked about energy systems here in the past so it’s relevant to this discussion if you’re considering lifting weights to failure.
If you lift weights to failure at or above about 12 reps of your maximum ability, you’ll actually train more of the glycolytic and possibly aerobic energy system component of your muscles, specifically the mitochondria and you’ll increase the muscle cells ability to uptake oxygen.
This can be useful for endurance athletes, or as an approach to training to provide a new stimulus (remember change is important still).
If you lift to failure at about 6 reps or less, you’ll train more of the nervous system component and perhaps create more myofibril hypertrophy (types of muscle growth can be found in this article).
This type of hypertrophy takes significantly longer to develop but also appears to last significantly longer than Sarcoplasmic Hypertrophy, which is developed in the last rep range I’ll discuss.
If you lift to failure in 6-12 reps, this is generally acknowledged as the ‘bodybuilding’ style rep range, and will lead to sarcoplasmic hypertrophy more than the other rep ranges.
It’s important to remember that these are gross generalizations and are not always mutually exclusive, but depending on your desired outcomes, lifting to failure can be very useful or not very useful at all.
Now that all the science-y mumbo jumbo is out of the way, the the theoretical idea behind lifting to failure involves increasing the overall time under tension on the muscle, particularly through the eccentric muscle movement phase.
Ideally this does more damage to the tissue as a result, which in theory requires more androgenic hormone displacement and therefore induces more sarcoplasmic growth.
Don’t get me wrong, eccentric stress will generally make you much more sore than concentric stress.
i.e. walking down hill will make you more sore than walking up hill.
Eccentric stress is the lowering phase of lifting, or the absorption of force, and the concentric stress is the lifting phase or the displacement of force (Read this if you want a more complete explanation of what occurs in a muscle contraction).
However, in the grand scheme of things if eccentric stress was the only important thing then why do we see people put on muscle mass never lifting to absolute failure, and why do many others not gain much mass lifting to absolute failure all the time?
Probably because that’s not the only important factor, sleep, nutrition, etc… all play a role still.
I am going to define ‘lifting to failure’ as two separate ideas and make my recommendation for how to lift weights at the gym.
1) Technical Failure — Is the point where your technique breaks down, even if you can get one or two more reps out.
2) Absolute Failure — Is the point where you actually can’t lift something anymore
If you want to know if you should lift to failure, it’s important to distinguish between the two different styles.
I generally tell people they should stop lifting when they’ve reached technical failure, and this is particularly specific to my weight loss clients.
Meaning stop when your form starts to go even if you think you can hit a few more reps.
- Reduces the likelihood of injury.
- Improves motor unit performance
- Allows you to train heavier and tap the larger motor units (and muscle fibers) that have more predisposition for growth.
- Fatigues the muscle enough to still stimulate growth
- Reduces muscle soreness and recovery time – which increases your ability to train more frequently, and more frequent training leads to bigger/better gains, more quickly.
If or when you train to absolute failure your last 2-3 reps will almost always be executed poorly, which means your nervous system will start recruiting muscles that will alter the movement itself.
For example, you may feel or see your elbows flare out in a bench press movement as your body tries to recruit more accessory muscles to complete the lift.
Over time lifting to absolute failure like this this will usually lead to altering the correct movement pattern by embedding the wrong sequencing.
This will often lead to injury or at least stagnant progress, and it’s far harder to undo a bad habit than it is to create a good one the first time around.
Obviously getting a feel for what technical failure feels like requires some training time and practice, a good rule of thumb is to stop yourself one or two reps short or learn to stop when you feel your form starting to suffer.
This is not to say you can or never should lift to absolute failure (it’s especially useful for higher rep ranges to learn how to combat fatigue better), but rather it’s been my experience that as a percentage of your training program it should only ever be a very small percentage of the total volume – definitely less than 10%, probably closer to less than 5%
What do you think? Do you lift to complete failure, or does what I’m saying make sense?