Bro split training: Does the classic bodybuilder routine still work?

The classic bro split workout hits each muscle group once a week with high volume. Here is what the science says about muscle growth, strength, and whether this old-school plan still holds up.

The relationship

First, what is a bro split? A bro split is a workout schedule that trains each major muscle group once per week on its own day. A standard 5-day bro split workout looks like this:

• Monday: chest
• Tuesday: back
• Wednesday: shoulders
• Thursday: legs
• Friday: arms
• Saturday and Sunday: rest

These sessions usually use high training volume. Training volume means the total work you do, usually counted as sets × reps × load. The goal is to thoroughly fatigue a muscle, chase a strong pump, then give it nearly a week to recover and grow. Hypertrophy means an increase in muscle size.

The key relationship to understand is between training frequency, total weekly volume, and muscle growth. Large meta-analyses show that when total weekly volume is the same, training a muscle once per week or 2–3 times per week leads to similar hypertrophy in most people.^[1] In other words, how many hard sets you do each week matters more than how you split them across the week.

However, spreading volume across multiple weekly sessions can sometimes help you lift heavier per set, accumulate more quality reps, and recover better between workouts.^[1],[2] That is why some strength coaches prefer full-body or upper/lower splits, especially for beginners. A bro split concentrates that work into one body-part day, which some advanced lifters find better for focus and mind–muscle connection.

How it works

Training frequency and weekly volume

Most hypertrophy research suggests that roughly 10–20 hard sets per muscle group per week is a solid target for intermediate lifters, with beginners often needing less and advanced athletes sometimes doing more.^,[2] A bro split workout typically packs many of those sets into a single session for each muscle.

Meta-analyses show that when total weekly sets are matched, training a muscle once versus multiple times per week leads to similar gains in muscle size in the short to medium term.^[1] The main trade-off is that a very high number of sets for one muscle in a single day can reduce performance in later sets due to fatigue, which may lower the “quality” of work you do.

Intensity, load, and progressive overload

Intensity in lifting usually means how heavy a weight is compared with your one-repetition maximum (1RM), which is the heaviest load you can lift once with good form. For hypertrophy, working mostly in the 6–15 rep range at 60–85% of 1RM, and taking sets close to failure, is highly effective.^[3] Progressive overload means gradually increasing training stress over time, for example by adding weight, reps, or sets.

Studies comparing different rep ranges find that when sets are taken near failure and weekly volume is similar, a wide range of loads can build muscle effectively.^[3] A bro split naturally supports progressive overload because you repeat the same “chest day” or “back day” every week. That makes it easy to track small increases in load or reps on the same exercises over months.

Muscle damage, recovery, and soreness

Delayed-onset muscle soreness (DOMS) is the muscle ache and stiffness you feel a day or two after a hard workout. High-volume bro split sessions can create a lot of local muscle damage and DOMS, especially when you use new exercises or train with long ranges of motion. Research shows that muscle damage and soreness are not required for hypertrophy and, past a point, may interfere with training quality.^[4]

Because a bro split gives each muscle almost a full week to recover, it can work well if you like very hard, “all-in” body-part days. The flip side is that if soreness lingers, you have fewer chances that week to train that muscle productively. This is especially relevant for older lifters or those with joint issues, who may tolerate slightly lower per-session volume better.

Hormonal and nervous system demands

Heavy compound lifts tax your nervous system, which includes your brain and spinal cord and controls strength and coordination. More frequent practice of big lifts like squats and presses usually helps strength gains because you get more chances to refine technique and recruit muscle efficiently.^[5] Bro splits may not be ideal for maximizing strength on specific lifts, since you might squat or bench only once per week.

Resistance training also causes short-term increases in hormones like testosterone and growth hormone. These spikes are modest and do not appear to differ much between bro splits and higher-frequency programs when total work is similar.^[6] For men who are not gaining muscle despite consistent training and nutrition, it can be worth checking baseline testosterone. Meta-analyses indicate that symptomatic men with total testosterone below 350 ng/dL (≈12 nmol/L) or free testosterone below 100 pg/mL (≈10 ng/dL) are most likely to benefit from further endocrine evaluation and possible treatment.^[7]

Who a bro split works best for

Survey studies of physique athletes show that many bodybuilders successfully use bro splits or similar body-part routines, often with very high weekly volumes before competitions.^[8] For lifters who enjoy focusing on one or two muscles per day, who have at least 5 days per week to train, and who care most about muscle size and shape rather than maximum strength on a few lifts, a bro split can fit very well.

Beginners, people who can train only 2–3 days per week, or athletes who must balance lifting with sports practice may be better served by full-body or upper/lower programs. These plans give each muscle more frequent “practice” with lower per-session fatigue.

Conditions linked to it

A bro split is not a disease, but it is linked to certain training outcomes and risks. Knowing these can help you decide if this style makes sense for you and how to tweak it.

• Muscle size gains when volume is high enough. When weekly sets per muscle reach the 10–20 range and sets are taken close to failure, bro splits produce hypertrophy similar to higher-frequency splits in most research, especially in trained lifters.^[1]
• Possibly slower strength gains on key lifts. Meta-analyses suggest that training lifts like the squat or bench press at least twice per week is slightly better for maximal strength, even when volume is matched.^[5] A classic chest-day-only bro split hits the bench once a week, which may limit strength progress.
• Higher per-session fatigue and joint stress. Doing many sets for a single joint in one day, like 20–25 sets for shoulders or elbows, can increase cumulative strain on those joints. Over time, this may contribute to overuse issues such as rotator cuff irritation or elbow tendinopathy, especially with poor technique or minimal warm-up.
• Challenges for older lifters or those with limited recovery. Aging, poor sleep, high life stress, and some medical conditions can reduce your ability to recover from very hard single muscle days. These lifters may respond better to moderately hard, more frequent sessions spread through the week.

Limitations note: Most resistance training studies are relatively short (8–16 weeks), involve small groups, and rarely test pure “real world” bro splits with extreme volumes. Results give us strong clues, but there is room for individual variation and long-term effects are less clear.

Symptoms and signals

Use these signs to judge whether your bro split workout is serving you well or working against you.

• Good signals that your bro split is working:
  • You are adding small amounts of weight or reps to key lifts every 1–2 weeks.
  • Muscles feel worked and pumped after sessions, but soreness mostly fades within 48–72 hours.
  • Your joints feel stable, with only mild, short-lived aches.
  • You feel generally energetic, sleep reasonably well, and look forward to workouts.
  • Over 8–12 weeks, you can see or measure increases in muscle size in photos, measurements, or how your clothes fit.
• Warning signs your bro split may need adjustment:
  • Soreness in the same muscle lasts more than 3 days or is severe enough to limit daily activities.
  • Plateaus where key lifts have not improved for 4–6 weeks, despite consistent effort.
  • Persistent joint pain in the shoulders, elbows, knees, or lower back that worsens over time.
  • Feeling drained, irritable, or dreading workouts most days.
  • Unintended weight loss, poor sleep, or loss of sex drive, which can signal under-recovery or possible hormonal issues.

What to do about it

If you like the idea of a bro split, you do not need to abandon it for the latest training trend. Instead, set it up in a way that the evidence supports and your body can handle.

1. Get a clear picture of your starting point. Write down your current schedule, main exercises, sets, reps, and weights. Note any past injuries or cranky joints. If you have symptoms of hormone problems like very low energy, reduced sex drive, or unexplained strength loss, speak with a healthcare professional before making radical training changes.
2. Design an evidence-based bro split workout. Choose 4–6 exercises per day, aim for 10–20 hard sets per major muscle across the week, and keep most work in the 6–15 rep range with 1–3 reps “in the tank” at the end of each set.
3. Monitor progress and adjust every 4–8 weeks. Track loads, reps, body measurements, and how you feel. If progress stalls or pain builds, dial back volume slightly, add a “deload” week of easier training, or shift toward a slightly higher-frequency split.

Myth vs Fact

• Myth: “A bro split can’t build muscle because you only hit a muscle once a week.”
  Fact: Studies show that similar weekly volume can build similar muscle whether you train a muscle once or several times per week. Quality weekly workload matters more than frequency alone.^[1]
• Myth: “Bro splits are only for bodybuilders on steroids.”
  Fact: Natural and competitive lifters alike use body-part splits successfully. Drug use changes recovery capacity but does not make the split itself good or bad.
• Myth: “More soreness means more muscle growth.”
  Fact: High soreness mostly reflects muscle damage and novelty, not superior gains. Extreme DOMS can even reduce training quality and slow progress.^[4]
• Myth: “You can’t get strong on a bro split.”
  Fact: You can gain plenty of strength by pushing your big lifts hard once per week, especially as an intermediate lifter. However, if maximizing strength on a few lifts is your top goal, training those lifts 2–3 times per week is usually better.^[5]
• Myth: “If you miss a body-part day, your whole week is ruined.”
  Fact: You can easily move or combine sessions. For example, if you miss “arm day,” you can tack a few biceps and triceps sets onto chest or back later in the week and keep weekly volume on track.

Here is a sample 5-day bro split workout that follows current evidence:

• Day 1 – Chest + triceps
  • Barbell bench press: 4 sets × 6–8 reps
  • Incline dumbbell press: 3 sets × 8–10 reps
  • Cable fly or machine press: 3 sets × 10–15 reps
  • Triceps dip or close-grip bench: 3 sets × 8–10 reps
  • Overhead triceps extension: 2 sets × 10–12 reps
• Day 2 – Back + biceps
  • Pull-up or lat pulldown: 4 sets × 6–10 reps
  • Barbell or dumbbell row: 4 sets × 6–10 reps
  • Chest-supported row or cable row: 3 sets × 10–12 reps
  • Barbell or dumbbell curl: 3 sets × 8–12 reps
  • Hammer curl: 2 sets × 10–12 reps
• Day 3 – Shoulders
  • Overhead press: 4 sets × 6–8 reps
  • Lateral raise: 3 sets × 12–15 reps
  • Rear delt fly: 3 sets × 12–15 reps
  • Upright row or machine press: 2–3 sets × 8–12 reps
• Day 4 – Legs
  • Back or front squat: 4 sets × 6–8 reps
  • Romanian deadlift: 3 sets × 8–10 reps
  • Leg press or lunge: 3 sets × 10–12 reps
  • Leg curl: 3 sets × 10–12 reps
  • Calf raise: 3 sets × 12–15 reps
• Day 5 – Arms + extra weak points
  • Close-grip bench or dips: 3 sets × 6–8 reps
  • EZ-bar curl: 3 sets × 8–10 reps
  • Cable press-down: 2–3 sets × 10–12 reps
  • Preacher or incline curl: 2–3 sets × 10–12 reps
  • Optional extra 2–3 sets for lagging delts, calves, or abs

Keep 1–3 reps in reserve on most sets, and take only a few key sets all the way to technical failure, where you cannot complete another rep with good form. Track your loads and reps, and aim for gradual progression.

Bottom line

The bro split is not outdated junk or magic bodybuilding wisdom. It is simply one way to organize your weekly training. Evidence shows that a well-designed bro split workout can build impressive muscle if you hit enough weekly volume, push sets close to failure, and recover well. It may be slightly less efficient for peak strength and can stress joints if you cram in too much work in one day. If you enjoy the structure of dedicated muscle days and can train at least five times per week, there is no reason to abandon a bro split—as long as you run it with science, not just “bro logic,” guiding your choices.

References

1. Schoenfeld BJ, Ogborn D, Krieger JW. Effects of Resistance Training Frequency on Measures of Muscle Hypertrophy: A Systematic Review and Meta-Analysis. Sports medicine (Auckland, N.Z.). 2016;46:1689-1697. PMID: 27102172
2. Grgic J, Schoenfeld BJ, Davies TB, et al. Effect of Resistance Training Frequency on Gains in Muscular Strength: A Systematic Review and Meta-Analysis. Sports medicine (Auckland, N.Z.). 2018;48:1207-1220. PMID: 29470825
3. Schoenfeld BJ, Grgic J, Ogborn D, et al. Strength and Hypertrophy Adaptations Between Low- vs. High-Load Resistance Training: A Systematic Review and Meta-analysis. Journal of strength and conditioning research. 2017;31:3508-3523. PMID: 28834797
4. Damas F, Phillips SM, Libardi CA, et al. Resistance training-induced changes in integrated myofibrillar protein synthesis are related to hypertrophy only after attenuation of muscle damage. The Journal of physiology. 2016;594:5209-22. PMID: 27219125
5. Ralston GW, Kilgore L, Wyatt FB, et al. The Effect of Weekly Set Volume on Strength Gain: A Meta-Analysis. Sports medicine (Auckland, N.Z.). 2017;47:2585-2601. PMID: 28755103
6. Kraemer WJ, Ratamess NA. Hormonal responses and adaptations to resistance exercise and training. Sports medicine (Auckland, N.Z.). 2005;35:339-61. PMID: 15831061
7. Bhasin S, Brito JP, Cunningham GR, et al. Testosterone Therapy in Men With Hypogonadism: An Endocrine Society Clinical Practice Guideline. The Journal of clinical endocrinology and metabolism. 2018;103:1715-1744. PMID: 29562364
8. Hackett DA, Johnson NA, Chow CM. Training practices and ergogenic aids used by male bodybuilders. Journal of strength and conditioning research. 2013;27:1609-17. PMID: 22990567
9. . American College of Sports Medicine position stand. Progression models in resistance training for healthy adults. Medicine and science in sports and exercise. 2009;41:687-708. PMID: 19204579