Why You Feel So Good After Lifting Weights, According to Science

Peloton instructor Alex Karwoski started lifting weights seriously in college with his rowing team. Since then, he’s experienced a particularly positive reaction after some successful strength workouts. “That ‘high’ that some people talk about experiencing after lifting usually comes in the form of feeling productive and satisfied,” he says.

Alex largely credits the consistent and satisfying nature of strength training for his post-lift mood boost. “I’ve noticed how much lighter and springier I’ve felt after a hard lift circuit or something that required me to stick to the plan, week after week, and execute a progression,” he continues. “The simplicity behind ‘picking weight up, putting weight back down’ is what gives the body (and sometimes the mind) such a feeling of success.”

Other lifters say they experience a short bout of a euphoric feeling immediately after a productive gym day the way endurance athletes might describe the famous “runner’s high.”

So what’s actually going on in your body and mind when you feel good after lifting weights? Here’s what to know—and how to try to get more of that glowy feeling.

Why You Feel Good After Lifting Weights

First, a little background: All types of exercise can improve your mood and mental wellbeing, not just weight lifting. “For me, even when I’m having a rough day, I know that by simply moving my body, I will put myself into a better [headspace],” Alex says. “There is a tranquility that comes to me on occasion when my body is under stress that I’ve put it under.”

Most studies on the mental health benefits of physical activity focus on cardio exercise. But a growing body of research supports both anti-anxiety and anti-depressive benefits of consistent resistance exercise, according to a 2024 review published in the journal Trends in Molecular Medicine. That typically means just two strength training sessions a week—a general recommendation for healthy adults that few actually meet.

Here are reasons why you may feel good after lifting weights.

1. It Changes Levels of Feel-Good Brain Chemicals

A specific type of chemicals called endocannabinoids, which are natural mood modulators, may be behind that post-exercise euphoria some (lucky) individuals experience, colloquially known as the “runner’s high,” says Karly Mendez, PhD, a senior human performance specialist at Memorial Hermann Rockets Sports Medicine Institute. Our endocannabinoid levels increase after endurance exercise like long runs and have been linked to that post-cardio euphoria. 

But the research surrounding resistance exercise and endocannabinoids has been more mixed, says sport psychologist Judy L. Van Raalte, PhD, professor emerita of psychology at Springfield College. For example, in one small 2023 PLOS One study, endocannabinoid levels actually decreased after resistance training, but study participants still experienced an improvement in their mood. That led the researchers to conclude that “psychological changes with exercise likely occur through a wide variety of biological and environmental mechanisms.”

Still, other chemical changes may be occurring—specifically, lifting weights might increase levels of certain mood-related neurotransmitters in your brain. Serotonin, a hormone related to relaxation, and dopamine, a hormone responsible for positive emotions and a sense of reward, both increase with regular exercise, according to a 2024 review in Physical Activity and Nutrition.

Over time and with consistent effort, exercise, including lifting weights, can help reduce chronic inflammation all around your body as well. And because depression is also associated with higher levels of inflammation, exercise may help relieve inflammation-related mood symptoms, according to the Physical Activity and Nutrition study.

2. It Lowers Stress and Improves Sleep

Getting regular exercise of any kind is linked with lower stress levels and better sleep, both of which can improve your mood. Lifting weights is no exception, which is especially good news for people who don’t enjoy cardio workouts as much, Van Raalte says. 

While more studies are needed, researchers hypothesized in the International Journal of Environmental Research and Public Health that strength training might support healthy brain development in adolescents and teenagers in ways that could lead to lower anxiety and depression rates. And in a 2020 Preventive Medicine Reports study of nearly 24,000 German adults, researchers found any amount of muscle-strengthening workouts was linked with higher-quality sleep. 

While these effects probably won’t kick in immediately after a strength session, over time, less stress and more restful shut-eye can certainly improve your overall mood, Van Raalte reiterates.

3. It Makes You Feel Accomplished

Don’t underestimate the sense of accomplishment you might get from lifting. “You’ve done something to prove to yourself that your body is capable of moving, functionally, with weights,” Alex says. That’s no small feat!

Mendez agrees: “It blends physiological chemistry with psychology: You get a rush of feel-good chemicals and a tangible sense of mastery (you lifted a thing you couldn’t lift last week). That combination of progress plus control is a powerful mood booster.”

Simply knowing you successfully did something hard might be enough to have you floating on cloud nine as you leave the gym, Van Raalte says.

Are Certain Strength Workouts More Impactful on Mood Than Others?

As mentioned above, any type of exercise can go a long way for your mental health. But when it comes to strength training specifically, low and slow may be the way to go. One International Review of Sport and Exercise Psychology study found that strength workouts performed at a low to moderate intensity—think: 50–70 percent of your one rep max—are linked to the biggest improvements in mood.

Alex says he’s personally noticed mood-boosting benefits from a similar training regimen. “Keeping things simple, both in exercise itself and in the sets and reps, has enabled me to find routine in my lifting,” he says. 

You may also want to focus on compound movements (exercises that work multiple joints and muscle groups at the same time, such as squats, hinges, presses, and deadlifts), because they “deliver strong mood benefits via effort, novelty, and sense of accomplishment,” Mendez says.

Don’t overdo it, either: A focused 30–60 minutes may be more likely to leave you feeling successful and accomplished rather than crushed and drained, Mendez says. In fact, as little as 10 minutes of movement or one workout a week may make you feel happier.

Ultimately, it may take a little trial and error for you to find the movements and training schemes that make you feel your best after lifting weights. “The best program is the one you’ll do consistently and enjoy,” Mendez says.

And don’t feel pressure to match what someone else is doing. “Fitness social media shows all of these people doing all of these things and having a great time, and then that’s supposed to be all the evidence you need to just do what they’re doing,” Alex says. “Resist that. Find out for yourself what works. How your body moves, the weight it can maneuver, and the way you respond to resistance training is going to be far more valuable if you take the time to design and learn something for yourself!”

If you’re not sure where to start, check out Peloton’s strength classes and Programs. You’ll find options for every fitness level that take as few as 5 minutes to complete but can still leave you feeling accomplished, proud, and happy.

What to Know If Your Mood Dips Instead

“If your mood consistently worsens with training, reduce the intensity and/or volume, check your sleep and nutrition, and consider consulting a professional,” Mendez says. A worsened mood could be a sign of overtraining or of an underlying mental health condition that could benefit from treatment. 

And remember, strength training alone is likely not enough to manage your mood if something serious is going on. While exercise may be one generally helpful tool in supporting your mental wellbeing, it isn’t a replacement for mental health treatments recommended by your healthcare provider.

The Takeaway

While it may not be as well-documented as the “runner’s high,” some people say they experience a similar feeling of euphoria after lifting weights. Research hasn’t quite pinpointed the underlying mechanism behind why you feel good after lifting weights, but it may have something to do with changing levels of neurotransmitters or the sense of accomplishment that strength training can inspire.

Any kind of physical activity can help your mood. But if you’re specifically looking for a mental or emotional boost from your lifting routine, try starting with a training plan where you focus on doing a few sets of exercises at 50–70 percent of your one rep max. Aim to fit in at least two weightlifting workouts each week, but remember that something is better than nothing and just 10 minutes of movement or one workout a week is linked with feeling happier. Just be wary of overtraining and remember that exercise isn’t a substitute for other mental health treatments recommended to you by your provider.