Lunges & Split Squats: Common Mistakes, Knee Pain Fixes & Proper Form
Lunges and split squats are staple lower-body exercises for good reason. When performed well, they build strength, improve balance, and translate directly to real life.
But as trainers, we also see these movements done poorly far too often—leading to faulty movement patterns, knee discomfort, or simply missing out on the full benefit of the exercise.
In this blog, we’ll break down:
- Why lunges and split squats are so valuable
- The three most common faults we see
- Practical strategies we use with clients to clean them up and make these exercises feel stronger, safer, and more effective
Quick note on terminology:
Many people use the terms lunge and split squat interchangeably, and for simplicity, we’ll do the same here. Technically, a split squat stays in place (up and down), while a lunge involves stepping forward or backward.
Why Lunges & Split Squats Deserve a Spot in Your Program
When executed properly, lunges and split squats can:
Build Lower-Body Strength
They target the quads, glutes, hamstrings, calves, and hips—key muscles for powerful and resilient legs.
Improve Balance & Stability
Because they’re unilateral (single-leg) movements, they challenge your core and stabilizers, which is crucial for daily activities and long-term joint health.
Correct Muscle Imbalances
They help address left-to-right strength differences, reducing injury risk and improving overall movement quality.
Increase Mobility & Flexibility
They can stretch tight hip flexors and quads, improving range of motion and posture.
Support Functional Fitness
Lunges mimic real-life movements like walking, climbing stairs, and getting up off the floor.
Adapt to Any Level
They can be modified endlessly—forward, backward, walking, weighted, or supported—making them appropriate for beginners through advanced trainees.
The 3 Most Common Lunge & Split Squat Faults We See
Despite all those benefits, three issues show up again and again:
- The front knee collapses inward
- Not enough depth in the movement
- Knee pain during or after lunges
Let’s walk through each one—and how we address it.
Fault #1: Front Knee Collapsing Inward
When the front knee caves inward, it’s often a sign that the hip stabilizers aren’t doing their job. Over time, this can lead to inefficient movement and increased knee stress.
Strategy We Use: Wall + Yoga Block Feedback
Step 1: Isometric Stability Hold
- Stand close to a wall
- Place a yoga block between the outside of the front knee/shin and the wall
- Set up in a split squat position
- Brace the core, keep hips and shoulders level
- Gently press into the block so it doesn’t fall
Hold this position for 10–30 seconds, then switch sides.
The goal is to feel the outer hip muscles of the front leg working to stabilize the knee.
Step 2: Add Upper-Body Challenge
From the same setup, maintain pressure into the block while opening the shoulders as if pulling back a bow (in a bow and arrow).
This increases the demand on stability, body awareness, and control.
Step 3: Take It Away From the Wall
Move away from the wall and imagine the block is still there.
Perform 8–10 controlled split squats per side, keeping hips level and the knee tracking properly.
Step 4: Progress to Lunges
Once control is solid, transition to:
- Reverse lunges (stepping backward), or
- Forward lunges
All while maintaining proper knee alignment.
Fault #2: Not Enough Depth in the Movement
Limited depth is often blamed on flexibility—but just as often, it’s actually about confidence and balance.
Strategy We Use: Bottom-Up Lunges
Step 1: Start From the Bottom
Have the client begin with their back knee resting on a yoga block or pad.
From there:
- Rise up into the split squat
- Slowly lower back down
- Pause, reset balance, and repeat
This gives the client confidence in the bottom position.
Step 2: “Brush” the Block
After the first rep, lightly touch the knee to the block instead of resting fully.
Step 3: Reduce the Height
Lower the block over time.
No fancy equipment? A flat flip-flop works surprisingly well.
Mobility Assist (When Needed)
If tight quads or hip flexors are clearly limiting range:
- Perform a focused hip extension mobility sequence
- Then retry the lunge
Most clients are shocked at how much easier the movement feels afterward.
We also recommend doing this mobility work daily or at least 3x/week to support better movement across all lifts.
Fault #3: Knee Pain During Lunges
For many clients—especially those over 40—lunges can feel uncomfortable or even painful at first. If you’ve tried focused hip extension mobility and your knees are still talking to you, try the TKE split squat.
Strategy We Use: Banded TKE Split Squats
How to Set It Up:
- Loop a thick resistance band around a sturdy anchor (like a squat rack)
- Step the front leg through the band and position it behind the knee
- Step back to create tension
Execution:
- Perform split squats while actively straightening the front leg at the top
- Focus on tightening the inner quad (VMO) for a couple of seconds before the next rep
- Perform 10–15 reps per side
The band:
- Helps reduce pressure around the knee
- Encourages better quad activation
- Often makes the movement immediately more comfortable
Progressions:
- Add movement with reverse lunges in and out of the band
- After 2 pain-free weeks, consider light dumbbells
Final Thoughts
Lunges and split squats often aren’t the problem—how they’re performed is.
With the right setup, cues, and progressions, these exercises can:
- Build strong, resilient legs
- Improve balance and confidence
- Reduce knee discomfort rather than cause it
👉 Watch the accompanying videos to see these strategies in action and learn how we coach our clients toward better movement and long-term progress.
If lunges haven’t felt great for you in the past, chances are you just haven’t been shown the right approach—yet.
Contact info@pitraining.ca to get assessed by one of our professional coaches and