Lactic Acid Training: Everything You Need To Know

Photographed by Molly Cranna.
"Lactic acid training" is not a new skin serum, a non-dairy milk, or a breastfeeding technique. It's a strength-training method that people swear will help you build muscle faster than traditional workouts. Now, lactic acid training isn't necessarily something that a personal trainer or workout instructor would have you do. It's kind of a niche method that certain bodybuilders and gym rats thought up, and it took off with people looking to build muscle and lose fat, fast.
As the name suggests, lactic acid training is a technique that involves working out in a way that causes your body to produce a lot of lactate, which is a byproduct that's released as your muscles create energy during high-intensity workouts. When you're doing a tough workout, and your muscles start to burn, that's related to the buildup of "lactic acid" in your muscles. Additionally, lactate plays a role in generating the "growth hormone" that's responsible for increasing muscle mass.
If you're confused, that's because lactic acid training is kind of confusing. Basically, the belief is that by doing lots of repetitions (about 2-3 sets of 12-25 repetitions) of an exercise, using a relatively lighter weight (about 30% of your one-rep maximum), with very little rest between, you can build up the lactic acid in your body, and ultimately boost the amount of muscle you're putting on. Lactic acid training is seen as a shortcut of sorts among people looking to make a dramatic change to their physique through exercise.
So, should you incorporate this unconventional muscle-building method in your own workouts? Although it's kind of scientific and complicated, lactic acid training could be a good entry point for people who are just starting to strength train, according to Ben Lauder-Dykes, NASM certified personal trainer at Fhitting Room, a HIIT studio in New York City. Lifting heavy weights is certainly one great way to build muscle, but lactic acid training allows you to put your muscles under a lot of tension and stress in a safe environment, he says. "It's a good in-between: it gets you decent volume and work done, and challenges you muscularly and aerobically," he says.
There's one caveat with lactic acid training that you should consider: it can be rough on your body, and you have to "embrace the suck," Lauder-Dykes says. "It feeds into most people's mental ideal of training, where the more it burns, the more pain I feel in the moment, the more I'm getting from the workout," he says. It's a double-edged sword, though, because eventually you might burn out. "Some people enjoy the pain and want to continue doing it, but there comes a point in any training phase where... you can’t maintain that level of intensity," he says. The tough work also means you have to truly spend time recovering from your workouts, he says. That might require working with a trainer who can draft a specific plan for you incorporating rest days.
Another thing to consider? Lauder-Dykes says that the claims about lactic acid training are a bit exaggerated, especially the part about it magically making your muscles grow in a short amount of time. "Like most things in fitness it's definitely overhyped," he says. "There is definitely an increase in growth hormone, but it's not significant enough that it’d have a dramatic effect on your composition."
The thing is, people are always eager to try to find a way to fast-track results from workouts — from wearing waist trainers to drinking pre-workout supplements — and lactic acid training is just another one of these fads. You might be better off setting more realistic, achievable strength-training goals for your training sessions, rather than just lifting to get big muscles ASAP. For example, if you're trying to increase endurance, the American Council on Exercise suggests doing 12 or more repetitions per set. And if you're not sure what your goals even are, then you might want to talk to a trainer (they're there to help!).
While lactic acid training might work for someone's specific training plan, it may not be the best option for you. But lactic acid serums for your skin? Those are a different story.

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