There aren’t a lot of things you get to see transform right before your eyes. After all, a watched pot never boils, as the saying goes. That’s why it’s extra special when you do get to witness speedy change, especially when it has to do with your gains. It’s gratifying to see noticeable payoff when you’re exercising consistently—which is why so many athletes chase a muscle pump.

This growth spurt in your muscles is usually temporary, but it still plays a role in your overall progress. Keep reading to learn more about why the pump happens, how long it lasts, and what it means for your long-term goals.

What Is a Muscle Pump?

A “muscle pump” is slang for what’s technically called transient hypertrophy, or muscle growth that doesn’t last.

The term originated among bodybuilders, says Mike Stack, an exercise physiologist, certified strength and conditioning specialist, and president of the Physical Activity Alliance. Nowadays, however, it’s much more common to hear talk of a muscle pump in your local gym or on your TikTok feed.

And that makes sense, because it’s a sign any athlete can use to know they’re working with purpose. “A muscle pump is when your muscles feel full, tight, and swollen during or after training,” says Peloton instructor Jermaine Johnson. “It happens because blood and fluid rush into the muscle you’re working, increasing cellular pressure and making you feel temporarily bigger and stronger.”

This is a good thing, Stack explains. “Essentially, it’s a result of increased blood flow to skeletal muscle during exercise, which drives more oxygen and nutrients to the muscle.”

That influx of blood flow also cleans out byproducts of your body’s energy production process, Stack says, like lactic acid. “So it is blood and fluid accumulation inside of the muscle as a result of increased energy need and waste removal,” he says. In other words, your temporary muscle growth is basically your body’s road sign that says “construction ahead.”

How to Get a Muscle Pump

If you’re chasing a pump, you’re going to have to work for it. Generally, the more you contract a specific muscle, the more fluid builds up there. That’s why you typically need to do high-volume, moderate- to high-rep strength workouts with short rest periods to see a visible muscle pump, Jermaine says. “This training boosts blood flow in the muscle, which drives that pump response.”

So what does that look like, exactly? Stack recommends doing 10–15 reps with just 60–90 seconds of rest between sets. (Many of the strength workouts on the Peloton App and Strength+ App fit the bill!) Higher reps and less rest means more metabolites build up during the set, and there isn’t much time for your body to clear them out before you’re working again, he says. Put those two factors together and you’ve got yourself a bigger muscle pump.

Even though this type of strength training is the form of exercise that’s most likely to cause a muscle pump, there are certain types of cardio workouts that might still give you at least a bit of a pump effect. Stack points to downhill running as an example: The pressure and strain on your muscles as they’re lengthening (known as eccentric contraction) “can induce a fair amount of muscle damage and swelling,” he says. Next time you’re out for a trail run, take a look at your quads and see if you notice a difference!

Do You Get a Pump In Whatever Muscle You Do?

It would be a pretty satisfying and quick fix if you could get a full body pump from a few biceps curls, but it doesn’t quite work like that. You’ll only notice a pump (if you notice one at all) in the specific muscles you’re working. “You’ll feel the pump in the muscles being trained because the localized increase in blood flow and cell swelling only happens where you’re creating the most mechanical tension and metabolic stress,” Jermaine explains.

That said, you might not notice a pump at all—or you might only notice it in certain muscles, especially where you carry less body fat, Stack says. That’s just because with a smaller amount of fat, your muscles are more prominent and visible. He notes that because of where most people store body fat, the arms are probably the most likely spot where a muscle pump will show. 

How Long Does a Muscle Pump Last?

There’s no exact amount of time a muscle pump will linger. “The duration depends on hydration, nutrition, intensity, and even genetics,” Jermaine says. Typically, “once your body rebalances fluids and the heart rate comes down, the pump fades.”

But it may last a few days, especially if you’re working out a lot. “In the bodybuilding population, individuals who go four or five days without strength training will notice that they look visually smaller than what they were four to five days previously,” Stack says. That’s because they were exercising enough that they had essentially triggered a chronic muscle pump. But then, after a deload week, their muscles finally had time for the pump to fade away, he explains.

This is called sarcoplasmic hypertrophy, Stack says, which is “this low-grade level of inflammation and fluid buildup that sits inside of the muscle that does persist, provided that damaging resistance training is performed on a regular basis.” (That’s technically different from regular hypertrophy, or muscle growth—but more on that later.)

The key here, Stack says, is that “damage” factor. Strength training involves making tiny microtears in our muscle fibers. Then, when you’re sleeping and resting from activity, your body repairs these tears, building your muscles back bigger and stronger. But if you’re not working out hard enough to spark these microtears in the first place, you won’t see muscle growth nor a temporary muscle pump, Stack says.

Can Muscle Pumps Lead to Long-Term Growth?

A pump alone isn’t going to help you achieve your muscle-growth goals. It’s a less important driver of lasting muscle growth than other factors. But it’s still a piece of the puzzle.

First, you have to be challenging your muscles enough to create that healthy damage, as mentioned above, Stack says. And this should typically involve some heavier lifting at lower rep ranges. A research paper in the Strength and Conditioning Journal found a combination of pump-focused sessions and heavier lifting sessions is a good recipe for hypertrophy success. 

Another important driver of long-term muscle growth is what’s called mechanical tension, or how much tension or load you’re placing on your muscles, he says. Increased blood flow and metabolite buildup—aka a muscle pump—is the third factor, but it’s the smallest driver in this muscle-growth trio, he says. 

Still, some research illustrates how chasing a pump can contribute to your overall mission: In a small study in the Journal of Strength and Conditioning Research, researchers found that men who had bigger muscle pumps immediately after resistance training went on to have greater muscle growth afterwards too.

But again, it’s most worthwhile to prioritize the fitness basics that’ll help you build lasting visible muscle. “Long-term growth still comes from mechanical tension, progressive overload, and recovery over time,” Jermaine says. If you don’t progressively lift heavier weights or increase your training volume over time, you’re more likely to plateau instead of seeing continuous muscle gains. 

Don’t forget the other essentials of muscle growth, either: Stay consistent with your workouts, eat enough protein, get plenty of sleep, and include recovery days in your fitness routine. “The pump feels good, but those habits build the results,” Jermaine says. 

And don’t skimp on carbs, which give you the energy to train consistently and with intensity, or fats, which are involved in making the hormones you need to build muscle, Stack adds. (Bonus: Filling up on carbs might also give you a temporary boost in the size of your muscle volume, according to a small study performed on male bodybuilders published in the Journal of Sports Science & Medicine.) Plus, make sure you’re lifting weights at least two to three times a week so you can keep making progress, he recommends.

The Takeaway

A muscle pump is a temporary, visible increase in the size of a specific muscle you’ve been working due to an increase in blood flow and lactic acid buildup in the area. It’s typically triggered by high-volume, moderate- to high-rep strength training with short rest periods, and it can linger for a short post-workout period or up to several days. A pump may contribute to long-term muscle growth if you’re also following smart habits like eating enough protein, scheduling enough rest days in your workout routine, and consistently challenging yourself with hard workouts—but it’s not the most important piece of the muscle-building puzzle. 

It’s absolutely OK to enjoy the muscle pump while it lasts, but remember your work isn’t done. And if you don’t get a pump, remember that’s OK too! “Chasing the pump is fun, but don’t confuse it with progress,” Jermaine says. “Use it as a feedback tool; it shows you’re training with intent. Just remember that real gains happen between workouts during recovery and not just during sessions.”