5 Reasons You’re Not Building Muscle That Have Nothing to Do With Your Workouts

If you've been hitting the weights for a while and don't seem to be putting on more muscle — no matter how much you increase the volume of your workouts — you might be wondering what gives?

Sometimes your ability to build more muscle has nothing to do with what you're doing in the gym and everything to do with what you're doing outside of your workouts.

Here are five factors that might be holding you back from packing on lean mass and what you can do about it.

If you've been strength training for some time, it's harder — but not impossible — to put on a significant amount of muscle the way a beginner would.

In a widely cited May 2003 study in the ‌European Journal of Applied Physiology‌, new lifters gained three times as much muscle over 21 weeks compared to other lifters with a year or more of training experience.

After you lift weights, a chemical process called "muscle protein synthesis" (muscle building) spikes. When you're new to strength training, muscle protein synthesis stays elevated for around two days after each workout, compared to less than a day in more advanced athletes, according to this June 2015 research review in ‌Sports Medicine‌.

The reason for this isn't totally clear, but experts hypothesize that it may have something to do with changes in mRNA (an acid involved in protein synthesis) from training and sensitivity to the signaling pathways that activate exercise-induced muscle protein synthesis, among other factors, according to an October 2005 study in ‌The Journal of Physiology‌.

Protein is what your body uses to build muscle, so it's important to ensure you're getting enough of it throughout the day and especially after your workouts to support muscle repair and growth.

"You want to eat at least one gram of protein for every kilogram (2.2 pounds) of body weight each day. In other words, eat at least half your body weight in grams of protein. That's at a minimum," says Nick Tumminello, CPT, a personal trainer based in Florida and author of ‌Strength Zone Training‌‌.‌

For example, if you weigh 180 pounds, you should aim to eat 90 grams of protein daily.

In a small June 2020 study in the ‌International Journal of Sport Nutrition and Exercise Metabolism‌, female lifters who ate 1.13 grams of protein per pound of their body weight gained an average of 4.6 pounds of muscle over eight weeks.

Other lifters who ate 0.4 grams of protein per pound of their body weight over that same period only gained 1.3 pounds of muscle. The higher-protein group also lost more body fat over the same period.

If your goals are to gain muscle and lose weight, it's possible — but it isn't easy to do simultaneously.

"When you're in a caloric deficit and you're not eating enough to maintain size, what the body is going to do post-training first is repair. Then it's going to prioritize all the regular biological processes," says Alex Viada, CPT, owner of Complete Human Performance.

"If there are still resources leftover and if there's enough stimulus, it's going to put some effort into building muscle."

And by "enough stimulus," we mean you've got to put in extra work to build muscle while losing weight. In a March 2016 study in ‌The‌ ‌American Journal of Clinical Nutrition‌, scientists were able to help men lose weight and gain muscle by increasing their protein intake and doing intense exercise.

That said, "people can be eating enough protein, and not taking in enough overall calories needed for muscle growth," says Meredith Mack, a personal trainer and professional bodybuilder based in New York. The other calories need to come from carbs and fat.

Adenosine triphosphate (ATP) is the way your cells store and use energy. In order to have enough ATP within a cell to grow muscle, you need to have glycogen in the cell, which is made of carbohydrates.

"So you need those carbohydrates to keep the energy levels in every individual cell in the body topped up in order to actually grow," Viada says.

Diets that are too low in carbs (less than 30 percent of calories) and fat (less than 25 percent of calories) are associated with lower levels of the muscle-building hormone testosterone, according to a July 2019 research review in ‌Sports (Basel)‌.

When you don't get enough sleep, your mental and physical wellbeing suffers. And so does your ability to build muscle.

Getting less than seven hours per night decreases testosterone levels, reduces muscle protein synthesis and increases cortisol levels, according to a January 2021 study in ‌Physiology Reports‌‌.‌ Testosterone is a hormone that your body needs to build muscle, and elevated cortisol levels make it difficult to put on lean mass. Lack of sleep also shortens the amount of time muscle protein synthesis happens.

"You don't need to get [eight hours] each night, but you do want to average eight hours of sleep each night throughout the week," Tumminello says. That could mean seven hours one night, and nine on another.

The quality of your sleep matters, too, Viada says. Restorative zzz's at night are what you need for muscle recovery and growth.

"Six hours with good quality sleep architecture is probably better than eight hours of absolute garbage sleep," he says. Sleep architecture refers to the amount of time you spend in the different phases of sleep: light sleep, rapid eye motion (or REM) sleep and deep (or slow-wave) sleep.

"The sleep phases all have different effects on melatonin and antioxidant release. Without sufficient antioxidant release in the gut, you start to get a build-up of reactive oxygen species (the molecules that cause inflammation in the body). When there's inflammation, your body is less likely to build muscle," Viada says.

Whether it's world events, work deadlines or personal issues, increased stress not only messes with your head but your muscle growth, too.

"The biochemistry of stress absolutely puts your body in a state where actual anabolic processes, including muscle building and sex drive. All those things are plummeting," Viada says.

Chronic stress shifts your hormonal balance, lowering levels of anabolic hormones that promote the growth of skeletal and lean mass, and increasing the levels of muscle-destroying hormones, according to a March 2015 study in ‌Biodemography and Social Biology.‌

Stress even makes your muscles do a poor job of contracting. In a small January 2014 study in the ‌Journal of Clinical and Diagnostic Research‌, researchers found that when people were experiencing more stress, their muscles weren't able to contract as hard or as well, which is essential for their growth.