Mastering the Squat: A Trainer’s Guide to Form, Function, and Fixes

When it comes to foundational exercises, few moves rival the squat. Whether you're building strength, improving mobility, or simply training for everyday life, squats are an essential part of the fitness toolbox.

But squatting isn’t just about bending your knees and dropping down, it’s a full-body movement that demands awareness, control, and proper mechanics.

“A squat is, by the fitness definition, a level-changing movement where the body moves from an upright position to a lower position by bending at the hips, knees, and, to a smaller degree, the ankles,” explains ISSA Master Trainer Jenny Liebl.

How to Perform a Proper Squat

Start standing upright with your feet just outside hip-width. Keep a soft bend in the knees and engage your core, not by bracing as if you’re about to be punched, but by gently pulling your belly button in toward your spine. Keep your gaze forward, chin level, and your neck neutral.

As you begin the movement, hinge from the hips and bend the knees. Your hips will move slightly back, like you're sitting into a chair. Go as low as is comfortable, ideally, until your thighs are just below parallel with the ground. Then press through your midfoot to return to standing, extending the knees and hips. Your glutes should fire at the top, but avoid locking your knees before your next rep.

Watch the Movement in Action

Goblet Squat Demo - Ideal for beginners or clients learning to brace, hinge and sit into the movement safely

Barbell Back Squat Demo - For clients with solid squat mechanics who are progressing to loaded lifts

Common Mistakes to Avoid

Even experienced lifters can fall into faulty movement patterns. According to Liebl, here are a few of the most common squat form issues, and how to fix them:

1. Looking up (Excessive Cervical Extension):
"This throws your spine out of alignment,” says Liebl. “Try to imagine holding a large orange between your chin and your chest throughout the entire movement to keep your spine neutral."

2. Overarching the Low Back (Lumbar Extension):
This often stems from poor core engagement. “It’s critical to strengthen the abdominals outside of the squat and maintain a slight tuck of the hips, a posterior pelvic tilt, during the movement,” she advises.

3. Knees Falling In or Out (Valgus or Varus Collapse):
Knee positioning is everything. “If the knees fall in, it’s often due to tight inner thighs and weak glutes,” says Liebl. “If they fall out, the hip flexors or outer calves could be the culprit.” Her advice? Get assessed by a fitness professional and work to stretch tight areas while strengthening underactive muscles.

As a rule of thumb, your knees should track in the same direction as your big toes throughout the movement.

Want to correct weak glutes and poor movement mechanics at the source? The ISSA Glute Specialist course dives deep into hip and glute dysfunctions, teaches proper activation and arms you with strength and hypertrophy strategies to rebuild from the ground up. By mastering glute-specific training Certified Personal Trainers can not only deliver better client outcomes but they can elevate their expertise and command higher rates for more specialized programming.

Squat Variations to Explore

Once you’ve nailed the basic squat pattern, there are countless ways to vary the movement.

“It can be helpful to remember the definition of the movement, a level-changing movement where you bend at the hips, knees, and ankles,” Liebl reminds us.

That includes classic box squats (perfect for beginners), as well as variations on machines like the angled leg press or hack squat. Split squats, which keep the feet stationary while moving up and down, are another great way to challenge balance and unilateral strength. Add dumbbells, elevate the feet, or adjust your stance to mix things up and keep progressing.

For trainers looking to refine these variations and apply targeting programming, ISSA’s Glute Specialist course provides the science-backed foundation. You’ll learn how to unlock hip mobility, assess client readiness and build programming that produces visible and functional results, setting you apart in a crowded field.

How Many Reps Should You Do?

If you're just starting out, aim for 3 sets of 10–15 reps, focusing on form over weight.

“Once you have proven proficient in the movement pattern and can control all elements (including abdominal bracing, knee tracking, and spinal stability) THEN it is appropriate to begin to add load and volume,” says Liebl.

And don’t rush it. “For beginners, quick reps can lead to injury,” she adds. “Use a controlled tempo, 2 to 3 seconds in each direction. This helps not only your muscles but also your nervous system learn how to properly execute and control the movement.”

The Bottom Line

Squats are a must-have in any fitness program but only if they’re done right. Focus on quality movement, develop core and glute strength, and progress slowly and mindfully. With expert guidance like that from ISSA Master Trainer Jenny Liebl, you’ll be squatting like a pro in no time.