{"id":"Barbell_Squat","name":"Barbell Squat","category":"strength","level":"beginner","equipment":"barbell","primary_muscles":["quadriceps"],"secondary_muscles":["calves","glutes","hamstrings","lower back"],"coaching_cues":["Drive your knees out","Big breath and hold your brace","Sit back into your hips","Spread the floor with your feet"],"common_mistakes":["Knees caving inward","Heels lifting off the ground","Rounding the lumbar spine (butt wink)","Losing upper back tightness"],"progressions":["Pause Squats","Low Bar Squat"],"regressions":["Goblet Squat","Box Squat"],"rep_ranges":{"strength":"3-5 reps × 4-6 sets","hypertrophy":"8-12 reps × 3-4 sets","endurance":"15-20 reps × 2-3 sets"},"contraindications":["Acute lumbar disc bulge","Severe knee osteoarthritis","Ankle impingement syndrome"]}