6.4 Single-Leg Squat, Push, Pull, and Gait Assessments

Single-leg squat assessment

The single-leg squat assessment (SLS) narrows the lens to one limb's frontal-plane control — closer to the demands of walking, running, and stair climbing than a two-legged squat. Setup: client stands with hands on hips, eyes forward, foot pointed straight, then squats on one leg to a comfortable depth and returns, repeating up to five reps per leg and comparing sides for asymmetry. The trainer watches the knee from the anterior view.

The primary compensation is the knee moving inward (dynamic knee valgus) — the femur internally rotates and adducts as the supporting hip fails to stabilize the pelvis.

Research NASM cites shows that people without knee valgus during the SLS recruit more gluteus medius and maximus and fewer adductors than those who collapse inward — which is exactly why the corrective answer activates the glutes (especially the posterior fibers of gluteus medius via slight hip extension during abduction) and inhibits the adductors and TFL. Underactive core stabilizers also contribute, so the activation position must let the client hold a neutral, stable spine.

Pushing and pulling assessments

The pushing assessment uses a standing cable or tube chest press; the pulling assessment uses a standing row. Both are performed in a split or staggered stance so the LPHC must stabilize while the arms move. Observe from the lateral view across ~5 reps. These tests are specifically good for exposing upper-body and cervical compensations that a squat does not load the same way.

Three compensations dominate:

The corrective implication mirrors Upper Crossed Syndrome: inhibit/lengthen the tight upper trap, levator scapulae, SCM (and pecs/lats), then activate the mid and lower trapezius, rhomboids, and the deep cervical flexors (a chin-tuck holding the head neutral throughout every exercise). Low back arching during a push/pull points the trainer back to core and hip-flexor work.

Gait observation and integration

Gait is observed informally — typically while the client walks on a treadmill or across the room — using the same five checkpoints. The trainer watches for excessive pronation, knee valgus, pelvic drop (Trendelenburg sign, suggesting a weak gluteus medius), trunk lean, and arm-swing asymmetry. Gait is qualitative on the CPT, not a scored protocol.

The purpose of all four tests is convergence: the OHSA flags whole-body patterns, the SLS confirms single-leg hip/knee control, the push/pull isolate the LPHC and shoulder/neck, and gait checks function in the most common daily task. When several assessments point at the same muscle group (e.g., a repeatedly underactive gluteus medius across OHSA knee valgus, SLS valgus, and gait pelvic drop), the trainer has a high-confidence, nonpainful target for corrective programming. Any painful, neurologically symptomatic, or grossly unstable finding still routes to referral, never a diagnosis.

Why the single-leg squat adds information the OHSA cannot

The overhead squat is a bilateral task: a stronger limb can quietly compensate for a weaker one, hiding an asymmetry. The single-leg squat removes that crutch by forcing one hip to stabilize the whole pelvis and trunk on its own, which is far closer to the real demands of gait, stair climbing, and most sport. A client who looks symmetric on the OHSA can reveal a clear side-to-side difference on the SLS — one knee tracking cleanly while the other collapses inward.

That asymmetry is high-value programming information, because the trainer can then bias corrective and unilateral work toward the weaker side rather than training both legs identically.

The gluteus medius is the star of this test. As a primary hip abductor and pelvic stabilizer, it prevents the opposite side of the pelvis from dropping (a Trendelenburg pattern) and stops the femur from internally rotating into valgus. NASM-cited research shows that individuals who keep a clean knee position during the SLS recruit more gluteus medius and maximus and less adductor activity than those who collapse — direct evidence for inhibiting the adductors/TFL and activating the glutes.

Sequencing and safety of the upper-body tests

The pushing and pulling assessments are typically run after the squat-based screens because they layer a dynamic upper-extremity load onto the standing LPHC. Use a manageable resistance, a staggered stance for a stable base, and watch the same checkpoints across the set rather than judging a single rep.

Across all four, the trainer is gathering converging evidence, never a label. Painful, unstable, or neurologically symptomatic responses stop the test and prompt referral; nonpainful findings feed the corrective continuum and the choice of OPT phase.