Most people think the hard part of a pushup is the way down. But the truth is, the top—the part where you straighten your arms—matters just as much. Skipping that final push means you’re leaving muscle growth on the table. If you want real results from your pushups, locking out fully is non-negotiable.
And if your goal is to build a stronger, more defined chest, locking out isn’t just about finishing the move—it’s where you squeeze and seal the deal. That full extension is a key part of perfect pushup form for chest development.
Full Extension = Full Muscle Activation
When you stop short and keep your elbows slightly bent at the top, your chest never gets that final squeeze. Locking out forces your pecs, shoulders, and triceps to fire together at their peak.
What happens when you lock out properly:
- Your chest muscles contract fully
- You build joint stability in your shoulders and elbows
- You complete the full range of motion, which leads to better strength gains
It’s like closing a door all the way instead of leaving it half-open.
It’s Not Just Straight Arms—It’s Tight Arms
Locking out doesn’t mean just straightening your elbows and relaxing. You need to push through your palms and feel your chest tighten at the top.
Try this:
- At the top of your pushup, press hard into the floor
- Squeeze your chest like you’re holding a piece of paper between your pecs
- Keep your core tight—don’t let your hips sag or rise
That little extra effort turns a decent pushup into a powerful one.
Skipping Lockout = Weak Gains
A lot of people rush through reps or stop just shy of full extension because it feels easier. But that “easy” version teaches your body to quit early.
Over time, that habit leads to:
- Less chest definition
- Poor shoulder alignment
- Plateaus in strength
Your muscles adapt to what you ask of them. If you never ask for full extension, they’ll never grow to their full potential.
Lockout Helps You Spot Bad Form
If you can’t lock out without your hips sagging or your shoulders shrugging, it’s a sign something’s off. Maybe your core is weak. Maybe your shoulders are tight. Maybe you’re doing too many reps too fast.
Use the lockout as a checkpoint:
- Can you hold a straight line from head to heels at the top?
- Do your shoulders feel stable—or strained?
- Are you breathing or holding your breath?
If anything feels shaky, slow down. Better to do fewer perfect reps than a bunch of sloppy ones.
It Builds Real-World Strength
Pushing something heavy across the floor, getting up from the ground, even opening a stuck door—all of these need that final “press” motion. Locking out in your pushups trains your body for those everyday pushes.
And because your chest works with your triceps and shoulders in real life, training them together through full reps builds functional strength—not just gym strength.
How to Practice Locking Out Right
Start simple. Do just 3–5 slow pushups focusing only on the top part:
- Lower with control (2 seconds down)
- Push all the way up until your arms are straight
- Hold for a beat, squeeze your chest, then go again
Once that feels solid, add it to your regular sets. You’ll notice your chest feels tighter, your posture improves, and your pushups get cleaner.
Common Mistakes Around Lockout
Even experienced people slip up here. Watch for these:
- Hyperextending elbows – Don’t shove past straight; just reach neutral extension
- Shrugging shoulders – Keep them down, away from your ears
- Rushing the top – Don’t bounce; pause and engage
- Holding your breath – Breathe out as you push up
Small fixes make a big difference.
Lockout Is Part of the Rep—Not the End
Think of the lockout as the finish line og the starting block. It’s where one rep ends and the next begins. If you’re loose or lazy at the top, the next rep starts weak.
But if you’re tight, tall, and engaged at the top, every rep builds on the last one. That’s how you get stronger, rep after rep.
Bottom Line
Pushups look simple, but the details decide your results. Locking out your arms isn’t just “finishing”—it’s where your chest gets its final, most powerful contraction. And that’s a must if you’re serious about building real upper-body strength.
Stick with perfect pushup form for the chest, and don’t skip the top. Your future self—and your reflection—will thank you.