Moment Arm
The perpendicular distance from the axis of rotation to the line of action of a force. Crucial for understanding leverage and resistance in lifting.
Why it matters:
A longer moment arm means more torque required, making a lift feel heavier. Optimizing moment arms improves efficiency and reduces injury risk.
Joint Stacking
Aligning joints (shoulder, hip, knee) vertically over the bar or line of force for maximum stability and force transfer.
Why it matters:
Efficient joint stacking minimizes energy leaks and allows you to lift heavier weights with less effort, preventing unnecessary strain.
RPE (Rate of Perceived Exertion)
A subjective scale (typically 1–10) used to measure the intensity of your effort during a set, helping to autoregulate training.
Why it matters:
RPE allows for flexible programming based on daily readiness, preventing overtraining and ensuring consistent, effective stimulus.
Bar Path
The trajectory of the barbell during a lift. Optimal bar path is often a straight vertical line over the midfoot.
Why it matters:
An efficient bar path minimizes horizontal displacement, reducing wasted energy and increasing the amount of weight that can be lifted.
Bracing
The act of creating intra-abdominal pressure by taking a deep breath and expanding your abdomen against your core muscles.
Why it matters:
Proper bracing stabilizes the spine and core, protecting against injury and allowing for more efficient force transfer during heavy lifts.
Progressive Overload
Gradually increasing the stress placed on the musculoskeletal system to stimulate adaptation and continuous improvement in strength or size.
Why it matters:
It's the fundamental principle of strength training. Without it, your body won't have a reason to get stronger or bigger.
Hook Grip
A grip where the thumb is pressed against the bar first and the fingers wrap over the thumb, locking it in place. Standard for the snatch and clean.
Why it matters:
Non-negotiable for Olympic lifting. The hook prevents the bar from spinning out of the hand during the pull — without it, peak velocities are lost and elbows turn over late on the catch.
Triple Extension
The simultaneous full extension of the ankles, knees, and hips at the top of the pull. The single most important power moment in the snatch and clean.
Why it matters:
Almost every Olympic-lift miss traces back to incomplete or out-of-sequence triple extension. FormForge measures the timing offset between the three joints — the "TES" reading.
TES (Triple Extension Speed)
FormForge's signature metric: the angular velocity (deg/s) of ankle + knee + hip extension during the second pull, peak-detected from BlazePose landmark trajectories.
Why it matters:
TES correlates with vertical bar velocity on the snatch and clean. Tracking TES across sessions shows whether your "explosive" intent is actually producing speed — or just feeling fast.
Catch Depth
The hip-crease height at the bottom of the receive position in the snatch, clean, or overhead squat. Lower catch = less bar travel required = heavier loads possible.
Why it matters:
Catch depth is the cheapest free strength gain in weightlifting: developing the mobility to receive 5 cm lower can mean 5 kg more on the bar with no extra force production.
Sinclair Score
A body-weight-adjusted total used by the IWF to compare lifters across weight classes. Calculated from the athlete's total (snatch + clean & jerk) and a coefficient indexed to current world records.
Why it matters:
When you can't change weight classes, Sinclair tells you whether you're actually getting better — independent of bodyweight drift. It's the metric that decides "best lifter" awards at most meets.
Velocity-Based Training (VBT)
Programming based on bar speed (Mean Propulsive Velocity, MPV) instead of fixed %1RM. Recent meta-analyses show VBT matches PBT for strength while improving daily regulation.
Why it matters:
Your real 1RM changes daily (sleep, stress, fueling). VBT lets the bar speed pick today's load — so heavy days stay heavy and recovery days stay honest, without a coach needing to be in the room.