Some things are meant to go together: peanut butter and jelly, salt and pepper, macaroni and cheese. But when it comes to one particular pair, people seem uncertain about their compatibility: exercise and alcohol.

The unlikely combo comes up more often than you might expect. After all, post-work workouts typically coincide with post-work happy hours. For ambitious, athletic socializers, there may be temptation to do double duty.

But is it OK to hit the gym after a few drinks, or even one boozy libation? Here’s what you need to know.

First thing’s first: When you sip an alcoholic beverage, you’re not just bringing on a buzz; you’re kicking off a series of physiological changes.

Once you swallow the alcohol, it goes to your stomach and gets absorbed in the small intestine. It then travels throughout your bloodstream, affecting the major parts of your brain, protein synthesis, hormones, and more.

“Many people are aware of the common effects of alcohol, such as flushing of the skin, impairment of judgment and coordination, and gastrointestinal problems,” says Michael Richardson, MD, a Boston-based One Medical provider. “What people are less aware of is the strain it puts on the cardiovascular system. It can cause high blood pressure, and chronic heavy alcohol use can lead to heart failure.”

The rate at which all the short-term physiological events happen, however, depends on a lot of factors, including your sex, weight, how much you’ve had to eat, and more.

But what happens when you try to get a workout in when you’re under the influence?

The most glaringly obvious issue with drinking and exercising is, of course, impaired coordination, balance, and judgement.

Alcohol has a tendency to lower inhibitions and affect brain chemistry (yes, even after just one drink). That means you could seriously injure yourself, or those around you, in a plethora of ways — even if you think you feel fine.

“The more likely risks that result from working out after a heavy night of drinking is still being impaired when you go to the gym,” Richardson says. “If you are still feeling weak and slightly tipsy, it’s best to take a rest day instead of potentially falling on your run or dropping a weight on yourself.”

Alcohol is a diuretic, so it increases your need to urinate. Combined with workout sweat, and you can easily become dehydrated.

“Dehydration and muscle fatigue are the most common results of a big night out,” Richardson says. “There are, of course, other, more serious risks, such as a heart arrhythmia, but this is more common in the case of heavy binge drinking or chronic alcohol use.”

Alcohol is a depressant, meaning it slows you down. Your reaction time, strength, endurance, and aerobic capacity will all likely suffer, so your workout won’t just be potentially dangerous — it’s bound to be less than optimal.

The full effects of alcohol aren’t immediate. You may not feel buzzed or even drunk until you’re well into your workout, which can set you up for serious injury.

“Just because you drink alcohol doesn’t mean you have to skip a workout, but you do want to make sure you’re recovered from your night out before you stress your body further,” Richardson says. “Even if you feel fine, it is important to make sure you are well hydrated before you exercise to prevent muscle cramping or passing out.”

Alcohol has a profound effect on the body, Richardson explains, so it’s best to avoid it if you’re looking to be at your physical peak the next day.

“I get it,” says Stephanie Schultz, fitness coach and founder of Courageously Confident. “You want to have that ‘hashtag balanced lifestyle,’ so hitting up happy hour and then going to the gym makes sense.

“But here’s the thing: You’re going to get to the gym and probably be so unfocused that your workout is going to feel crappy and you won’t reap the benefits. If I were you, I’d hit up the gym first thing the next morning. Or hit up the gym and then go for a drink.”

Experts agree mixing alcohol with fitness isn’t a great idea. But if you’re dead set on making an appearance at happy hour and a p.m. workout, make sure you at least do all of the following to minimize your risk for serious injury:

  • Wait as long as possible between drinks and exercise. “The first step is to just wait. A standard unit of alcohol is typically cleared from the body in one to two hours,” Schultz says.
  • Drink tons of fluids, and keep the workout short. “The next step is hydration, followed by hydration, and finishing with more hydration. No one wants to get hurt during their workout, so it’s important to prime your body and play it safe before you take on rigorous exercise,” Schultz says.
  • Eat a solid meal before you drink. The food will slow down the absorption of alcohol. Keep in mind you’ll need to move around later, so anything too heavy might slow you down even further.
  • Keep things light and as low intensity as possible. Now is not the time to try Barry’s Bootcamp or hot yoga.

The bottom line: The best thing you can do is skip your workout. No, it’s not ideal, but you’ll be in a way better position to crush it (and less likely to crush yourself) if you come back sober the next day.

Michelle Konstantinovsky is a San Francisco-based journalist, marketing specialist, ghostwriter, and UC Berkeley Graduate School of Journalism alumna. She’s written extensively on health, body image, entertainment, lifestyle, design, and tech for outlets like Cosmopolitan, Marie Claire, Harper’s Bazaar, Teen Vogue, O: The Oprah Magazine, and more.