Research
Mixed
Maintaining a neutral spine and upright trunk posture during squats minimizes compressive and shear forces on the lumbar spine, whereas forward lean or lumbar flexion significantly increases injury risk.
Keep your back straight and your chest up when you squat. Leaning forward or rounding your back puts dangerous pressure on your discs and ligaments. If you can't stay upright, lighten the weight.
GoodSupportsHIGH confidence
Squatting with a flexed lumbar spine decreases the moment arm for the lumbar erector spinae, reduces tolerance to compressive load, and results in a transfer of the load from muscles to passive tissues, heightening the risk of disc herniation... shear forces during squatting have been found to be significantly higher as lumbar flexion increases from the neutral position.
Why this rating
Supported by multiple studies on spinal kinetics (Adams, Cappozzo, McGill).
Source
Squatting Kinematics and Kinetics and Their Application to Exercise Performance
Brad J. Schöenfeld · The Journal of Strength and Conditioning Research · 2010
DOI 10.1519/jsc.0b013e3181bac2d7
narrative_reviewCited 520×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- Performing squats to depths greater than 90 degrees of knee flexion does not increase ACL or PCL injury risk and may enhance joint stability through increased soft tissue constraint, while maximizing quadriceps and gluteus maximus activation.Good
- Front squats produce significantly lower maximal joint compressive forces at the knee and reduced lumbar stress compared to back squats, while maintaining similar quadriceps and hamstring activity.Good
Related findings · Mixed
- Bariatric surgery (VSG and RYGB) is the most effective and sustainable treatment for obesity, producing marked and sustained weight loss that non-surgical interventions cannot match.Strong
- Severely protein-deficient diets (2–3% energy) induce lean body mass loss and metabolic imbalance, whereas adequate protein intake (0.66 g/kg/d minimum) is a prerequisite for maintaining muscle, bone, and physiological function.Strong
- For patients with Class III obesity (BMI >39.9 kg/m2), metabolic bariatric surgery (MBS) is significantly more effective than any currently approved medication, with BilioPancreatic Diversion (BPD) showing the highest estimated weight loss.Strong
This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →