You don’t need decades of research to tell you that cyclists (and runners and rugby players and other hard-exercising folks) often enjoy a post-workout beer… or two… or well, more. But science does indeed show a connection between exercise and alcohol consumption, with the most active people tossing back more booze than those who exercise less.

There are many theories as to why, with some animal studies showing that exercise may cause a "cross tolerance” to alcohol, so it takes more booze to feel the buzz. Or it might reflect the “work hard, play hard,” ethos athletes often share. Whatever the case, while a beer or two after a hard ride or race won’t likely wreck your recovery and subsequent gains, there are ample reasons to turn off the tap before it becomes a binge. 

As evidence, we turned to alcohol and exercise researcher Evelyn Parr from the Centre for Exercise and Nutrition at Australian Catholic University to explain what happens to your body when you chase down a hard ride with one (or more) too many.

Your liver is too bombarded to do its job

Your liver is too bombarded to do its job
Photograph by S_Bachstroem/Getty Images

 

As the organ responsible for mopping up all the metabolic byproducts from a hard sweat session, your liver remains in high gear long after you’ve racked your bike and walked into the bar. Pour a bunch of ethanol in there for it to cope with on top of all the lactate? Something’s gotta give, and it’s generally your recovery, says Parr. “Alcohol consumption seems to blunt the liver’s typical post-exercise recovery process,” she says. Instead of breaking down the lactate and turning it into glucose and restocking its glycogen stores, your liver is busy firing up alcohol dehydrogenase enzymes to clean up the sudden toxic spill.

Your muscles can’t repair properly

Your muscles can’t repair properly
Photograph by Robert Niedring/Getty Images

 

Hard training rides and races damage your muscle fibres. Good recovery, such as plenty of food, fluid, and rest helps to repair and make them stronger. Too much alcohol interferes with that process, says Parr. "When alcohol is consumed, especially in large doses, your body isn’t as efficient at making new proteins that are the building blocks of muscle, even if you’ve consumed protein at the same time.”