15-07-2025
Sports Scientist Reveals the One Thing Most Guys Get Wrong About Bulking
Whenever they're making decisions about nutrition and muscle gain, powerlifters and hardcore lifters have to ask themselves: What's the best way to bulk? Gaining weight might seem pretty straightforward—just eat more than you burn, right? Turns out, how you go about it makes all the difference.
Take the 'dirty bulk,' for example. The term was born in the powerlifting world and refers to a muscle-gaining strategy where you eat way more calories than you burn, without caring too much about food quality. The goal? Pack on muscle and strength as fast as possible. And yes, it works, but not without consequences.
"Slow, smooth, and steady is 100 percent the rule with bulking," Mike Israetel, Ph.D., exercise scientist and co-founder of Renaissance Periodization, said in a recent video. "Gaining weight too fast is just not a good thing."A dirty bulk is all about calories, and lots of them. That often means loading up on fast food, sugary snacks, and highly-processed comfort meals that make it easy to blow past your daily intake. The upside? Dirty bulking practically guarantees size and strength gains, which can be a blessing for hardgainers who've been stuck in neutral. But it's a slippery slope.
Compared to a cleaner, more structured bulk, this approach can leave you with a lot more fat to cut later. As Isratel puts it, there's a right way to bulk, and there's a way that'll leave you with more belly than biceps.
"If you gain weight really, really fast, you bloat up so quickly that your cardio goes to shit," Israetel says. "Your lower back and calves start to get too pumped, and your cardiovascular [system] starts limiting your lifting. So sets of 15 on the leg press start to turn into no more than five RIR [reps in reverse], no fewer than five RIR to the muscle. Your muscle is just like way, way, way away from failure because your lungs and breathing go, because your gut's so big."
He goes on to explain that packing on weight too quickly, like you would with a dirty bulk, not only tanks your cardio, but throws off your body mechanics, too. In other words, if you're looking to bulk the smart way, "slow and steady" wins the muscle-building race.
Sports Scientist Reveals the One Thing Most Guys Get Wrong About Bulking first appeared on Men's Journal on Jul 15, 2025
