Ever tried to chug through curls after a heavy squat day and wondered why your muscles feel so different? Training for size and training for strength might live under the same gym roof, but they speak very different languages. One pushes your neural pathways to their limit, teaching your body to recruit every single fiber; the other starves you of oxygen until your muscles beg for mercy. If you’ve ever felt like your program is missing a spark, maybe it’s because you haven’t quite picked your side—size or strength. Sound familiar?
In a recent video that’s equal parts brainy and brutally honest, Mike Israetel—Ph.D., exercise scientist, and one of the minds behind RP Strength—dives headfirst into the messy, often misunderstood split between training for size and training for strength. He doesn’t just toss out textbook definitions either; he lays out how knowing the difference can actually help you stop spinning your wheels and start seeing real results.
Exercise Selection: Isolation vs. Compound
In hypertrophy mode, you’re an artist sculpting each muscle head. Think dumbbell bicep curls, tricep kickbacks, or those front-foot elevated Smith machine lunges that seem awkward until you feel the glute and think, “Okay, this is something.” You aren’t battling the heaviest weight; you’re waging war on every last fiber of the targeted muscle. The goal? Relentless tension and stretch that scream, “Grow!”
Switch over to strength training and the world shrinks to heavy metal and full-body coordination. You’re not wondering how much your glutes are firing in isolation—you’re asking how big that number on the bar can get. Bench press, squat, deadlift: your holy trinity. These lifts don’t care about finesse; they care about moving weight. And that translates directly to bigger numbers on the scoreboard.
Rep Ranges: The Numbers Game
Let’s talk numbers—painful ones. For pure strength gains, you’ll live in the three-to-six-rep zone. It’s like sprinting at max speed: short, explosive, and leaving you questioning life choices.
Sets of five to ten reps hit a sweet spot between power and pump. I’ve personally cranked out eight reps on leg press one day just to test my limits—and, oh boy, my quads filed a formal complaint afterward. Powerlifters swear by this middle ground when they need both size and steel.
Hypertrophy opens the gates wider: anywhere from five up to thirty reps, as long as you’re flirting with failure. Yes, thirty reps on the leg extension machine feels like being trapped in a small room with a jackhammer. But that gut-wrenching, high-rep finish line is where soreness turns into real, visible growth. Trust me, you’ll feel it tomorrow—and the day after.
Volume: The Unsung Hero
Here’s where the rubber meets the road: weekly volume.
- Strength: 5–15 sets per muscle group or movement.
- Size: Push that to 10–30 sets, ideally settling between 20–30.
Sounds like a lot? It is. I once shot for thirty sets on chest in a single week—looked like a science experiment with extra data points. Did it work? Hell yes. Did I need two extra sauna sessions to recover? Also yes. If your chest at eight sets feels like a dusty attic, give it more traffic. Don’t rush in; ease into added volume.
It’s a delicate dance. Strength-focused weeks might see you smashing five heavy sets, while hypertrophy-centric phases smack you with back-to-back pump sessions. Your body learns adaptation through variety, not monotony.
Putting It All Together
Here’s the bottom line: pick a goal, then tailor your exercise choices, rep ranges, and volume accordingly. Trying to grow and get stronger at exactly the same time? You’ll make some progress, but probably slower. Lean into one objective, crush it, then circle back for the other.
Consider block periodization: three months of size focus followed by three months of strength. Or rotate every four weeks between heavy triples and high-rep blasts. It might feel like juggling—because it is—but the payoff comes when your bench PR coincides with arms that actually pop in a muscle tee.
Which challenge will you pick first? Share your hypertrophy-vs-strength war stories in the comments below. Hit us up on Facebook and Instagram for daily no-BS gym wisdom, and let’s keep grinding—and growing—together.
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Sources:
- www.mensjournal.com/health-fitness/exercise-scientist-explains-difference-between-training-for-size-versus-strength
- www.barbend.com/mitchell-hooper-mike-israetel-training-for-size-versus-strength/
- www.rpstrength.com/blogs/videos/strength-vs-size-whats-the-real-difference
