Is It Actually Safe to Train to Failure?

You might have heard weight room talk from super muscular lifters about training to failure and thought, "That sounds counterproductive!" But here's the twist: In this case, failure can actually lead to success.

Training to failure means completing rep after rep after rep of an exercise until you couldn't possibly do another — even if someone were going to give you a million dollars. If it sounds hardcore, that's because it is, but it can also be an effective way for more advanced lifters to build strength when gains have plateaued.

Keep reading for a lesson in failure — plus expert insights on the benefits of training to failure and how to tell if it's right for you and your fitness goals. (Spoiler alert: It's not for newbies!)

Understand this: Training to failure (sometimes called training to concentric failure), is not the same as failing a rep. "When you're training to failure, you're intentionally getting to a point where you fail a rep," says Alena Luciani, CSCS, founder of Training2xl.

Need an example? Let's consider the biceps curl. Your program might entail doing 3 sets of 10 reps, followed by one set to failure. That would mean cranking out reps until you hit a point where you can no longer physically bring the weight up to your shoulders.

"The biceps curl is the perfect example of an exercise you might train to failure," says exercise physiologist Pete McCall, CPT, CSCS, host of the All About Fitness Podcast. That's because it's an isolated movement.

In general, training to failure is best for single-joint movements, like the biceps curl, hamstring curl, seated row and tricep extension, or body-weight movements like push-ups or pull-ups.

"You wouldn't train to failure with a compound movement like the squat clean and jerk or snatch," Luciani says. "The danger if you actually fail a rep of these highly skilled movements is too great." (And a March 2019 study published in Strength and Conditioning Journal agrees.)

Read more: The One Trick to Help You Lift More Weight Instantly

That's a hard no. "Training to failure should be reserved for athletes whose lifting age is at least 5 years old," Luciani says. As far as she's concerned, for beginner or intermediate lifters, training to failure is far too risky to be beneficial.

For the general population, consistency is the most important element of any exercise routine, McCall says. And when someone is super sore (or injured), it ultimately interferes with that bottom line.

For beginner and intermediate athletes, Luciani recommends training to fatigue instead. Basically, this means leaving a little something in the tank. "I like to use the two-rep rule, which means the last two reps are challenging, but you're stopping a movement when you still have two or three reps in reserve," she says.

OK, so should all experienced lifters train to failure? Again, no. "It's best for a professional athletes in the off season and someone training for a specific goal, than for Joe Schmoe who has some strength training experience," McCall says. "Bodybuilders and powerlifters commonly incorporate training to failure."

He adds: "I can't understate how hard it can be psychologically to train to failure. It's tough work pushing yourself that hard, and it's not something every exerciser is willing or able to do."

It sounds obvious, but as you're nearing failure, it's easy for technique to go out the window. "During a movement like the dumbbell shoulder press or biceps curl, when you're tired, it's very easy to arch your back and put your spine and lower back in a bad position," Luciani says.

This can cause anything from a slipped disc or muscle strain to an overuse injury over time. In fact, researchers from the a May 2007 study published in the Journal of Strength and Conditioning Research explicitly state, "Training to failure should not be performed repeatedly over long periods, due to the high potential for [...] overuse injuries."

Of course, there's also the risk of dropping a weight and — if you don't have a trained spotter — breaking your toes, or in the case of chest or bench press, breaking a rib.

Also consider that when you train to failure, you're breaking down the muscle fibers. While some breakdown is good and necessary for muscle growth, too much breakdown can cause them to release a byproduct (called myoglobin) into the bloodstream, which in excess can cause kidney damage.

Likely you've heard of this condition by another name: rhabdomyolysis or rhabdo. McCall Says, "Anytime you push yourself to or past your limits you're at a risk of getting rhabdo, and that's especially true if you're training to failure multiple days in a row." (which, for the record, you shouldn't do).

And then there's the soreness. "The delayed onset muscle soreness (DOMS) is going to be real," McCall says.

"When you strength train, you engage the motor units in your muscle," McCall says. "When you strength train to failure, it means that you have engaged all the muscle motor units, and that there are no more muscle units left to engage in order to help you complete the rep."

In essence, this means that you're training the muscle as completely as possible. The 2007 Journal of Strength and Conditioning Research study concluded that through greater activation of muscle motor units, periodically training to failure can help athletes break through strength plateaus.

The researchers added that training to failure may increase the secretion of growth-promoting hormones, like HGH and testosterone. McCall says that's because the body secretes more of these growth-promoting hormones because there's more damage to the muscle than when you stop a set before failure, and the hormones are needed for muscle repair.

A July 2016 study published in the Journal of Applied Physiology also found that those who trained to failure saw an increase in their bench press one-rep max, which suggests it can be an effective way to improve absolute strength. And a July 2012 study published in the Journal of Applied Physiology found training to failure can also be used to induce muscle hypertrophy (aka increase muscle size).

Read more: 13 Benefits of Weight Lifting That No One Tells You About

If you've been training for several years, have a solid base of strength and want to take things to the next level, your best best is to work with a strength coach who can develop a training plan built to help you meet your goals, Luciani says.

Because if your goal is to hit a snatch PR at your next powerlifting competition, your program needs to look different than someone who wants to break through a back squat plateau or someone who wants to put on lean mass for a bodybuilding competition.

Next, understand that training to failure is best done occasionally, and only for 8 to 12 weeks at a time. "After that, your body becomes exhausted and isn't going to recovery as well," McCall says. Even within a training to failure phase, he says you shouldn't be training to failure more than one or two days a week — more than that and the risk of injury increases.

"You also want to make sure you're doing everything you can to help your muscles recovery after a training to failure session: eating adequate protein and carbohydrates, managing your stress levels, and sleeping well," McCall says.