Eccentryx / Exercise Atlas / legs
Wall sit (60–90 s isometric)
Back flat on wall, thighs parallel to floor, knees at 90°, hold position.
Muscles
- Primary
- quads
- Supporting
- glutes, knee stability
Mechanics
- Pattern
- knee flexion
- Equipment
- bodyweight
- Geometry
- Variable Range
- Energy model
- Glycolytic Pathway (10-90s)
- Target feel
- Quad burn builds steadily; no joint motion — pure time under tension.
- Progression
- Add a plate on the thighs or progress to single-leg wall sit.
- Regression
- Higher knee angle (less than 90°) to reduce quad demand.
Watch for
- Letting thighs rise above parallel over time
- Pushing off knees with hands to cheat
- Feet too close — puts excessive stress on knees
Substitutions
- Leg extension isometric hold
- Spanish squat (band, knee-over-toe)