Reps Do Matter: How Training Volume Drives Hypertrophy (and How to Use It Without Beating Up Your Joints)
If you’ve been training for a while, you’ve probably heard two statements that sound like they contradict each other:
“You can get strong on low volume.”
“You need more volume to grow.”
Both can be true, especially for trained lifters.
A great example is the Schoenfeld, Contreras, Krieger, Grgic, and colleagues study, “Resistance Training Volume Enhances Muscle Hypertrophy but Not Strength in Trained Men” (published in Medicine & Science in Sports & Exercise). In that study, trained men followed the same exercises, the same frequency (3 days/week), and the same rep range (8–12 reps), but with different set volumes:
1 set per exercise
3 sets per exercise
5 sets per exercise
Here’s the punchline you’ll see me return to throughout this blog:
Strength and endurance improved in all groups, and the groups weren’t meaningfully different.
Muscle growth improved in all groups too, but higher-volume training produced greater hypertrophy at key sites (like elbow flexors and parts of the thigh).
That’s a big deal because it shows something lifters need to hear clearly:
If your goal is hypertrophy, volume matters.
And yes, reps do matter, because reps are one of the biggest levers you can pull to create the right amount of volume and stimulus while managing injury risk.
Let’s break this down in a way that makes it easy to apply.
What Is Hypertrophy?
Hypertrophy is the increase in muscle size, specifically the size of muscle fibers and the overall thickness/cross-sectional area of a muscle.
There are different “flavors” of hypertrophy discussed in training circles, but you don’t need to overcomplicate it. In practical terms, hypertrophy is what happens when consistent training causes your body to add muscle tissue so you can better handle future demands.
Hypertrophy isn’t just “looking bigger”
Muscle growth matters because it impacts:
Strength potential (more muscle cross-sectional area generally supports more force production)
Joint stability (muscle helps control movement and absorb load)
Performance (bigger engines tend to produce more output)
Injury resilience (more capacity often means more tolerance)
Body composition and health (muscle supports metabolic health and long-term function)
Even if your main goal is strength, hypertrophy is often the foundation you build on, especially once you’ve been lifting long enough that beginner gains are long gone.
The Key Concept: Volume Is a Major Driver of Hypertrophy
Training volume is typically described as the amount of work you perform. In the Schoenfeld study, volume was manipulated in the simplest, most coach-friendly way: number of sets per exercise.
All groups trained 3 days per week for 8 weeks using:
Bench press
Military press
Lat pulldown
Seated row
Back squat
Leg press
Leg extension
They trained in the 8–12 rep range and took sets to momentary concentric failure (meaning they couldn’t complete another rep with proper form).
What happened?
Everyone got stronger and improved endurance.
But the high-volume group gained more muscle in several measured areas.
That supports the idea that hypertrophy has a dose–response relationship: as volume increases (within recoverable limits), hypertrophy tends to increase.
This is why reps do matter. Reps are a tool for building volume and creating the stimulus your muscles need to grow.
Why “Reps Do Matter” (and What People Get Wrong About It)
When someone says “reps don’t matter,” they usually mean:
“You can build muscle across a wide range of rep ranges.”
That part is mostly true if you’re training hard enough and doing enough total work. But here’s the practical reality:
Reps change the stimulus and the cost
The number of reps you choose affects:
Load (intensity): higher reps usually mean lighter weights
Joint/tendon stress: heavier weights generally increase peak stress
Fatigue type: higher reps increase metabolic fatigue and local burn
Technique quality: very heavy reps can break down form; very high reps can also degrade form when you’re gassed
Total volume accumulation: moderate/high reps often make it easier to accumulate productive work without hitting “max effort” loads
So yes: you can grow with low reps, moderate reps, and high reps… but the way you get there, and the risk profile, changes.
The “Safety Benefit” of Higher Reps: Less Intensity, Less Tendon Overload
You asked for a key point: high reps matter because they allow you to drop intensity and avoid overwhelming tendons and causing injury.
That’s a smart coaching lens.
Why heavy lifting can beat up tendons
Tendons adapt, but they generally adapt slower than muscles. Heavy, high-intensity training (especially near max effort) can create:
Higher peak forces
Higher joint compression and shear in some lifts
More connective tissue strain per rep
More “spiky” stress (big stress peaks instead of smoother accumulation)
This isn’t a reason to fear heavy training. It’s a reason to program intelligently.
Why higher reps can be joint-friendlier (when done well)
With higher reps:
The load is lighter
Peak stress per rep is lower
You can accumulate a lot of muscle stimulus without repeatedly handling near-max weights
You often get more “time under tension,” which can be hypertrophy-friendly
You can build volume with less orthopedic cost for many lifters
That makes higher-rep training a great option for:
Lifters with cranky elbows, shoulders, knees, or hips
People returning from injury
Older lifters
Lifters who already do heavy work and need a safer way to add more hypertrophy volume
Anyone who wants growth without living in the danger zone every session
Important note: high reps aren’t automatically safe if form collapses. The safety comes from lighter loads plus good execution.
What the Schoenfeld Study Suggests About Time Efficiency
One of the most interesting lines of the study was essentially this:
The low-volume group trained ~13 minutes per session (because it was one set per exercise).
They still improved strength and endurance meaningfully over 8 weeks.
But the higher-volume groups trained longer and gained more muscle in several sites.
This is a huge practical takeaway:
If your goal is strength and basic performance…
You can get a lot done with surprisingly small time investments, especially if effort is high and exercise selection is solid.
If your goal is hypertrophy…
You likely need more weekly work, and that means more sets, more reps, more total training volume.
In other words:
Strength can improve on a “minimum effective dose.”
Hypertrophy tends to reward higher doses (up to your recoverable limit).
The Hypertrophy “Recipe” You Can Actually Use
Let’s turn this into coaching practice.
1) Choose a rep range that matches your joints and your goal
A simple hypertrophy-friendly spread:
Main lifts: 5–10 reps (moderate-heavy, good tension)
Secondary compounds: 8–15 reps
Isolation/accessories: 12–25 reps (often easiest on joints)
This aligns perfectly with your point: high reps help manage intensity and can keep training safer for tendons.
2) Train close to failure, but don’t be reckless
In the study, sets were performed to momentary failure. That’s useful for research, but in the real world:
Most lifters grow well at 0–3 reps in reserve (RIR) for hypertrophy work.
Taking everything to failure can create too much fatigue and reduce weekly volume quality.
A strong approach:
Isolation work: closer to failure more often
Big compounds: close, but not constant grinders
3) Use volume progression (the simplest way to “apply the study”)
Since the study showed higher volume produced greater hypertrophy, a very practical approach is:
Start at a recoverable baseline
Build volume over weeks
Deload when needed
Repeat
Example progression for a muscle group:
Week 1: 10 working sets/week
Week 2: 12
Week 3: 14
Week 4: 8 (deload)
Repeat slightly higher next cycle
How Many Sets Do You Need for Hypertrophy?
The Schoenfeld study used 1 vs 3 vs 5 sets per exercise, 3 days per week. The highest volume group often saw the greatest muscle thickness gains.
That doesn’t mean “everyone must do 5 sets on everything forever.”
It means:
If you’re trained, very low volume may maintain strength and still cause some growth, but higher volume increases the odds of better hypertrophy.
The sweet spot is the most volume you can recover from while still progressing.
A realistic guideline:
Beginner: 6–10 sets per muscle per week
Intermediate: 10–16 sets per muscle per week
Advanced: 12–22+ sets per muscle per week (highly individual)
And for many lifters, the easiest way to push volume without joint pain is exactly what you said:
higher reps with slightly lower intensity.
Why Higher Volume Didn’t “Win” for Strength in the Study
This is where people get confused, so it’s worth addressing clearly.
In the Schoenfeld study:
Strength improved in all groups
But there weren’t significant differences between groups
Why might that happen?
1) Trained lifters often need specificity for strength
Strength is skill + neural efficiency + muscle. If you want maximal strength, you usually need:
heavier loads sometimes
practice with lower rep sets
more specific strength programming
The study had everyone in the 8–12 rep range, which is hypertrophy-friendly but not as strength-specific as frequent heavy practice.
2) More volume also creates more fatigue
Higher volume can produce more fatigue, which might blunt peak strength expression, especially if recovery isn’t perfect.
3) There may be a “threshold”
Once you hit a certain amount of productive volume for strength, extra sets may not add much, especially in a short time frame.
That’s why the study is so useful: it highlights that hypertrophy and strength don’t always respond to volume the same way.
How to Build a “Reps Do Matter” Program (That Stays Tendon-Friendly)
Here’s a practical template you can use while keeping intensity controlled and connective tissue happier.
The weekly structure (3 days/week)
This mirrors the study’s frequency (3 nonconsecutive days), which makes recovery manageable.
Day 1 – Full Body (Tension focus)
Squat or Leg Press: 3–4 sets of 6–10
Bench Press: 3–4 sets of 6–10
Row: 3–4 sets of 8–12
Split Squat or Leg Extension: 2–3 sets of 12–20
Triceps + Biceps: 2–3 sets of 12–25
Day 2 – Full Body (Volume + joint-friendly reps)
RDL or Hamstring Curl: 3–4 sets of 8–12
DB Incline Press: 3–4 sets of 10–15
Lat Pulldown: 3–4 sets of 10–15
Leg Press: 3–4 sets of 12–20
Lateral Raises: 3 sets of 15–25
Day 3 – Full Body (Pump + accessories)
Front Squat or Hack Squat: 3–4 sets of 8–12
Close-Grip Bench or Machine Press: 3–4 sets of 8–12
Seated Cable Row: 3–4 sets of 10–15
Leg Extension: 3–4 sets of 15–25
Curls + Triceps Pressdowns: 3–4 sets of 12–25
This setup uses:
Moderate reps for compounds
Higher reps for accessories
Enough volume to chase hypertrophy
Lower peak intensity to reduce tendon overload risk
Technique and Tempo: The “Hidden Safety Lever”
If you’re going to use high reps to manage intensity, you also want to manage sloppiness.
A simple rule:
If your last 5 reps look like a different exercise, the set is too long.
Try:
Controlled eccentric (2–3 seconds down)
Smooth concentric (no jerking)
Stop 1–2 reps earlier when form breaks
This keeps your “high rep = safer” plan actually true.
Nutrition and Recovery: Volume Only Works if You Can Recover
In the Schoenfeld study, they monitored diet and even provided protein on training days. That’s not accidental, volume-driven hypertrophy depends on recovery resources.
If your volume goes up, your recovery has to rise too.
Priorities:
Protein: roughly 0.7–1.0 g per lb of body weight per day (adjust based on preference/body size)
Calories: growth is easier in a slight surplus
Sleep: your best legal performance-enhancing drug
Deloads: planned reductions in volume keep you progressing longer
Common Mistakes When Chasing High-Rep Hypertrophy
Mistake 1: Turning every set into cardio
High reps should still be challenging for the muscle. If you’re stopping 10 reps short, it’s mostly junk volume.
Mistake 2: Ignoring progression
More reps, more sets, or more load over time is the engine. If nothing progresses, hypertrophy stalls.
Mistake 3: Going high-rep on everything
Some muscles and lifts respond better to moderate reps. Use high reps strategically, especially for accessories and joint-sensitive movements.
Mistake 4: Skipping exercise variety when joints complain
If elbows are mad, swap barbell curls for cable curls or hammer curls. If shoulders are mad, use dumbbells or machines. The goal is hypertrophy stimulus, not loyalty to a tool.
Putting It All Together: The Big Takeaways
Let’s tie this back to the article, because this is the heart of your blog:
The Schoenfeld study shows that trained men can gain strength even with very low volume, but hypertrophy improves more when volume increases.
That supports the real-world coaching truth: if you want to maximize muscle growth, you must manage volume intentionally.
Reps do matter because they’re a primary way to accumulate volume and stimulus.
High reps matter because they let you reduce intensity, lower peak tendon stress, and safely accumulate more hypertrophy-friendly work, especially when paired with good form and smart exercise selection.
The “best” approach for many lifters is a blend:
Some moderate-rep work for tension and skill
Plenty of higher-rep work for volume and joint-friendliness
Progressive overload over time
Recovery that matches the workload
References:
Schoenfeld BJ, Contreras B, Krieger J, Grgic J, Delcastillo K, Belliard R, Alto A. Resistance Training Volume Enhances Muscle Hypertrophy but Not Strength in Trained Men. Med Sci Sports Exerc. 2019 Jan;51(1):94-103. doi: 10.1249/MSS.0000000000001764. PMID: 30153194; PMCID: PMC6303131.