The Role of Eccentric Loading in Muscle Growth
Why slowing down the lowering phase builds bigger, stronger muscles
What Is Eccentric Loading?
In strength training, every lift has three phases:
- Eccentric = Muscle lengthens under load (e.g. lowering the bar in a bench press)
- Isometric = Muscle contracts with no movement (e.g. pausing at the bottom)
- Concentric = Muscle shortens (e.g. pressing the bar up)
Eccentric loading refers to placing strategic emphasis on the lengthening phase of a lift—typically by slowing it down, overloading it, or isolating it.
Why It’s Critical for Hypertrophy
Greater Mechanical Tension
Muscles can handle more force eccentrically (up to 120–140% of concentric strength), making it an ideal stimulus for mechanical tension — a primary driver of hypertrophy.
More Muscle Damage
The eccentric phase causes greater muscle microtrauma, which—when managed well—leads to superior muscle rebuilding and size increases.
Higher Recruitment of Type II Fibers
Slower eccentrics activate fast-twitch muscle fibers, which are more prone to hypertrophy than slow-twitch fibers.
Research Summary
| Study Outcome | Summary |
| Roig et al., 2009 | Eccentric training resulted in greater hypertrophy and strength than concentric-only training. |
| Schoenfeld, 2017 | Controlled eccentrics (2–4 sec) led to more muscle growth than faster, uncontrolled movements. |
| Douglas et al., 2017 | Eccentric training improves muscle architecture (fascicle length + pennation angle), beneficial for strength. |
How to Implement Eccentric Loading
Tempo Training
- Prescribe a tempo like 3–1–1 (3 sec down, 1 sec pause, 1 sec up)
- Slows the eccentric phase to increase time under tension
Eccentric-Only Sets
- Use supramaximal loads (110–120% 1RM) with spotter help on concentric
- Advanced method, ideal for experienced lifters only
Paused Eccentric-Isometric
- Add a pause mid-way through the eccentric (e.g. halfway down a squat)
- Builds control, joint stability, and tension
Single-Limb Eccentrics
- Concentric with both limbs, eccentric with one (e.g. Nordic hamstring curls, split squats)
Coach’s Caution: Recovery
- Eccentric overloads generate high DOMS (delayed onset muscle soreness)
- Program sparingly: 1–2 eccentric-focused sessions per week max
- Combine with full recovery strategies (sleep, nutrition, deloads)
Takeaway for Trainers
Eccentric loading is undervalued in most training programs, but it’s an elite method for boosting hypertrophy, strength, and neuromuscular control.
✔️ Use tempo
✔️ Periodize it into phases
✔️ Monitor recovery
With the right balance, eccentric training unlocks some of the most potent adaptations available in strength science.