Here’s what a doctor advises if you suffer from nausea and vomiting from a weightlifting workout.

“A major cause of nausea and vomiting with weightlifting is doing too much, too quickly, without adequate preparation,” begins Marc I. Leavey, MD, a primary care physician with 40-plus years of experience, who writes his blog, STRING OF MEDICAL PEARLS.

“While you should be well-nourished and well-hydrated before vigorous exercise, you need time to digest the food, and let the majority of it leave the stomach.

“Otherwise, that adrenaline rush that you get when you start an exercise set will do just what it does at other times, shut down digestion, divert blood to the arms and legs, and empty out the GI tract.”

Look at it this way: The body is hardwired to summon up certain biochemical responses to a perceived danger.

When you begin a hardcore weightlifting session, the body can’t tell if this is an encounter with a wild boar or a safe training routine inside a building. So the body starts gearing up for a fight or flee response.

To prepare for the fight or escape from danger (a physiological response that came in very handy during caveman times), the body empties the GI tract—you puke.

But why? So that the body could rid as much baggage as possible to be as efficient as possible during the fight or escape from “danger.”

This is why sometimes, a person will upchuck or at least suffer nausea simply upon viewing a grisly scene, such as the aftermath of a motorcycle accident.

Think of the contents of your gut as the equivalent of carrying a weighted rucksack. The rucksack would be a hindrance if you had to fight or run from danger.

So the body should shed it.  Likewise, you vomit when faced with what the body perceives as a threat.

And let’s face it—a grueling set of deadlifts and squats could fool the body into thinking it’s time to dump the baggage.

Dr. Leavey explains, “Better to have a healthy meal, give time to digest, and start the routine a bit slower to allow the body to acclimate.

“Clearly, as you get more into exercising, this should become less of a problem, but early on it can be a limiting factor.”

Maybe you’ve read that prior to lifting weights you should ingest a good heap of protein. Give a bit more time between doing this and starting your working sets.

Also, as Dr. Leavey says, pay more attention to the warm-up. Don’t just dive into your maximal loads.

To further help prevent vomiting during or after a weightlifting routine, eat something at the 45 minute mark (and this time lapse excludes warming up). It should be a combination of protein and quick-acting carbohydrates.

Another factor in the barfing up or at least feeling nauseous during weight training is that of having an untrained body, in combination with lack of nourishment. When I used to be a personal trainer at a gym, the only clients of mine who ever experienced nausea and a little upchucking were not well-trained, and a few of them had not eaten much in the preceding hours.