Can You Skip Leg Day for a Bigger Upper Body? (Science Says Yes)
Key Points
Lower body training does not significantly enhance upper-body muscle growth.
Hormonal spikes from leg exercises (testosterone, growth hormone) don't meaningfully affect upper-body hypertrophy.
Heavy lower body training may actually steal recovery resources that could be better used for upper-body development.
Sprinting and athletic drills can improve fat loss and physique definition, but won't build upper-body muscle.
If the goal is purely upper-body aesthetics, you can skip leg training without sacrificing results.
Introduction
At Verro, we train a lot of people who want to get stronger everywhere.
But people have different goals, and we reflect that in programming. You might want to grow your arms, or develop your shoulders. In which case we'd ramp down volume for other body parts to reallocate resources to the desired area. But it got me thinking... could you totally ignore one body part to maximize adaptations in another area? In other words: "If I only care about my arms, chest, and abs, do I even need to train legs?"
It’s a fair question — especially if your goal is aesthetic and not athletic.
Before we go any further: if you were focused on longevity, injury prevention, or general physical resilience, lower body training would absolutely be essential. Strong legs and hips are foundational for aging well and maintaining independence. But that's not what we're talking about today. Today, it's purely a thought experiment: How do you maximize upper-body hypertrophy for looks, and is leg day pulling you off course?
So let's get nerdy about it: Does lower body training help you build a better-looking upper body? Or can you skip it without consequences?
We'll walk through the research, the theories, the real-world experience, and what to actually do in the gym if upper-body aesthetics are your only goal.
Should You Train Legs for Upper-Body Growth?
The Hormone Spike Myth
Let's start with something you might or might not have heard before: big lifts like squats and deadlifts create a short-term rise in anabolic hormones like testosterone and growth hormone (West et al., 2009).
This sounds promising. More hormones = more muscle, right? Not so fast.
Studies show that while squatting or sprinting can spike hormones for an hour or two, it doesn't translate into extra growth in muscles you didn’t directly train (West, 2009; Morton, 2011).
Muscle growth is localized: it happens primarily where you apply mechanical tension and volume, not from systemic hormone spillover.
In other words, squatting heavier won’t make your arms bigger — curling heavier will.
The body doesn't hand out participation trophies. You grow the muscles you hammer consistently, not the ones you neglect and hope hormones will bail out.
Systemic Fatigue: The Hidden Cost
Heavy leg training isn’t free. It taxes your central nervous system and recovery capacity (Schoenfeld, 2010).
Think of your recovery like a bank account. Every heavy squat, every lunge, every RDL you push through is a withdrawal. Your body only has so many resources to allocate toward muscle repair and growth each week. Spend too much on legs, and there’s less left over for your bench press, pullups, rows, and curls — the lifts that actually make your upper body bigger.
If you care mostly about upper-body size, a brutal leg day could interfere more than it helps. You're adding stress to the system without a matching payoff upstairs. Smart programming is about resource management as much as it is about hard work.
Now that we understand why systemic fatigue matters, let's dive deeper into the evidence behind skipping leg day without hurting your upper body gains.
What the Research Says About Skipping Legs
Several well-controlled studies have directly tested whether skipping lower-body work negatively affects upper-body growth. The answer? Not really.
One standout study by West et al. (2009) tracked participants who trained one arm by itself, and the other arm after a heavy lower-body workout to spike systemic hormones. Despite a large hormonal surge from the leg training, both arms gained the same size and strength. The takeaway? Transient hormone boosts from legs don't translate into greater upper-body hypertrophy.
Morton et al. (2011) conducted a comprehensive review and came to a similar conclusion: post-exercise hormonal responses are not meaningfully associated with muscle growth outcomes. Local muscular tension, not whole-body hormones, is what drives gains.
Other studies compared groups performing heavy leg work alongside upper-body routines versus those who did upper-body only. Consistently, they found no significant difference in upper-body muscle hypertrophy between groups (Rønnestad et al., 2011).
In short: if you're hitting your chest, back, arms, and shoulders with enough direct volume, you don't need "assistive" hormones from leg day. You grow what you train. Period.
Now, if you want bigger quads or glutes? Different story. But if your primary aesthetic concern is from the waist up, you can skip leg training without sabotaging your results.
It taxes your central nervous system and recovery capacity (Schoenfeld, 2010).
Think of your recovery like a bank account. Every hard set you do takes a withdrawal. Your body only has so many resources to allocate toward muscle repair and growth each week.
If you blow a bunch of recovery capacity on squats, lunges, and Romanian deadlifts, there’s less left over for your bench press, pullups, rows, and curls — the lifts that actually make your upper body bigger.
If you care mostly about upper-body size, a brutal leg day could interfere more than it helps. You're adding stress to the system without a matching payoff upstairs.
Sprinting and Athletic Movements
What about sprinting? Or sled pushes? What about sled dog training? (Kidding. Mostly.)
These are excellent for fat loss, conditioning, and making your abs pop by lowering body fat.
But again — they don’t build upper-body muscle.
Sprinting spikes growth hormone temporarily (Gibala, 2012), but mainly benefits fat burning and leg musculature.
Sprinting can help show off the muscles you already have by keeping you lean. It’s a physique management tool, not a hypertrophy strategy.
In short: sprints might get you shredded, but they won’t put slabs of beef on your pecs.
Practical Takeaways
If your goal is purely upper-body hypertrophy, here are some useful rules of thumb:
Prioritize upper-body training: Spend your gym time hammering the muscles you want to grow. Chest, back, shoulders, arms, abs. Twice a week minimum, three times if you can recover from it.
Skip legs without guilt: You aren’t missing out on secret gains. Muscle is specific to what you train. No mystery hormones are coming to save your triceps if you skip curls to do Bulgarian split squats.
Optional: light leg work: If you want to hedge your bets, doing 2–3 sets of squats, leg presses, or sled pushes once a week won’t hurt — but it’s not necessary. Just keep it low-impact enough that it doesn’t bleed into your recovery.
Sprint strategically: Use short sprint sessions if you want to stay lean without wasting muscle mass, but don't overdo it. Think 6–10 sprints of 10–20 seconds, not running yourself into the ground.
Focus on big upper-body lifts: Heavy rows, chins, dips, and presses create a huge anabolic stimulus for the muscles you actually want to grow.
Bottom line:
You don’t need leg day to build a great upper body. You need consistency, volume, intensity, and recovery — all targeted where it matters.
Conclusion
Training legs when you’re chasing upper-body aesthetics is optional.
The data is clear: while heavy lower-body exercises like squats and deadlifts create short-lived hormonal spikes, these transient changes do not meaningfully enhance hypertrophy in muscles you aren't directly training. Multiple studies, including within-subject designs and systematic reviews, show that upper-body muscles grow just as well without lower-body workouts piggybacking on them.
In fact, focusing too much on heavy leg work can be a net negative if your goal is pure upper-body growth. Systemic fatigue can sap the recovery resources you need to optimize performance and progress on your rows, presses, pullups, and curls — the lifts that actually build the physique you're aiming for.
If you love training legs? Keep doing it. Lower-body strength and power are amazing attributes, especially for real-world athleticism, injury prevention, and long-term health. But if you're being ruthlessly specific about aesthetics — if you just want bigger arms, chest, shoulders, and visible abs — you have full permission to skip leg day or minimize it to almost nothing.
Smart hypertrophy training is about resource allocation. Direct tension, sufficient volume, controlled fatigue, and consistent recovery are what grow muscle. Not wishful thinking about hormone levels.
Train smart. Recover hard. Be specific. And don't let outdated fitness myths slow you down.
References
West, D. W. D., et al. (2009). "Resistance exercise-induced increases in putative anabolic hormones do not enhance muscle protein synthesis or intracellular signalling in young men." The Journal of Physiology, 587(21), 5239–5247. (Study showing no added hypertrophy from leg-induced hormone spikes.)
Morton, R. W., et al. (2011). "Acute hormonal responses are unrelated to the hypertrophic effect of resistance training: a systematic review." Sports Medicine, 41(12), 999–1017. (Systematic review concluding localized tension drives growth, not systemic hormones.)
Rønnestad, B. R., et al. (2011). "Acute hormonal responses to heavy-resistance exercise at moderate and high intensity levels." Journal of Strength and Conditioning Research, 25(4), 1073–1078. (Study on acute hormonal responses from different resistance intensities.)
Gibala, M. J., et al. (2012). "Physiological adaptations to low-volume, high-intensity interval training in health and disease." The Journal of Physiology, 590(5), 1077–1084. (Study showing sprint-induced hormonal spikes aid fat loss, not hypertrophy.)
Schoenfeld, B. J. (2010). "The mechanisms of muscle hypertrophy and their application to resistance training." Journal of Strength and Conditioning Research, 24(10), 2857–2872. (Comprehensive review of how muscles grow in response to training stimuli.). "Resistance exercise-induced increases in putative anabolic hormones do not enhance muscle protein synthesis or intracellular signalling in young men." Journal of Physiology, 587(21), 5239–5247.
Morton, R. W., et al. (2011). "Acute hormonal responses are unrelated to the hypertrophic effect of resistance training: a systematic review." Sports Medicine, 41(12), 999–1017.
Rønnestad, B. R., et al. (2011). "Acute hormonal responses to heavy-resistance exercise at moderate and high intensity levels." Journal of Strength and Conditioning Research, 25(4), 1073–1078.
Gibala, M. J., et al. (2012). "Physiological adaptations to low-volume, high-intensity interval training in health and disease." Journal of Physiology, 590(5), 1077–1084.
Schoenfeld, B. J. (2010). "The mechanisms of muscle hypertrophy and their application to resistance training." Journal of Strength and Conditioning Research, 24(10), 2857–2872.
DISCLAIMER
This article is for informational and educational purposes only and is not a substitute for medical advice, diagnosis, or treatment. Always consult with a qualified healthcare provider or certified fitness professional before starting any new training program, especially if you have any pre-existing health conditions or injuries. Individual results may vary, and adjustments to training volume, exercise selection, and intensity should be made based on your personal recovery capacity, experience level, and goals.