Understanding how the lifting and lowering phases build strength, muscle, and athletic performance.
Strength training is more than moving weight from point A to point B. Every repetition has distinct phases, and understanding them helps you train with purpose. The concentric and eccentric phases both contribute to strength and performance, but each offers a different training stimulus.
1. Concentric Loading — Producing Force
The concentric phase occurs when a muscle shortens while producing force. It is typically the lifting or overcoming portion of a repetition.
Examples:
- Squat: Driving out of the bottom position.
- Bench press: Pushing the bar away from your chest.
- Bicep curl: Curling the dumbbell toward your shoulder.
- Deadlift: Standing up with the bar.
Why it matters:
- Develops force production.
- Improves acceleration and explosive strength.
- Contributes to muscle growth.
- Improves performance in jumping, sprinting, and throwing.
When to prioritize it: When your primary goal is explosive power, acceleration, or improving your ability to produce force quickly.
What to expect: Greater emphasis on overcoming resistance and moving weight with speed and intent.
2. Eccentric Loading — Controlling and Absorbing Force
The eccentric phase occurs when a muscle lengthens while producing force. It is typically the lowering or braking portion of a repetition.
Examples:
- Squat: Controlling your descent.
- Bench press: Lowering the bar toward your chest.
- Bicep curl: Slowly lowering the dumbbell.
- Deadlift: Controlling the bar back toward the floor.
Why it matters:
- Develops muscular control and stability.
- Creates substantial mechanical tension.
- Contributes to muscle hypertrophy.
- Improves deceleration and force absorption.
- Develops strength while muscles lengthen.
When to prioritize it: When your goal is muscle development, improving movement control, or developing an athlete’s ability to decelerate, land, and change direction.
What to expect: Greater muscular fatigue and potentially more delayed-onset muscle soreness (DOMS), especially when introducing unfamiliar eccentric training or increasing volume.
3. Which Phase Should You Prioritize?
| Training goal | Primary emphasis | Reason |
|---|---|---|
| Muscle hypertrophy | Both phases | Develops muscular tension throughout the movement. |
| Explosive power | Concentric | Improves rapid force production. |
| Maximal strength | Both phases | Develops the ability to lift and control heavy loads. |
| Deceleration | Eccentric | Improves braking and force absorption. |
| Movement control | Eccentric | Reinforces positioning and technique. |
| Athletic performance | Both phases | Develops force production and force absorption. |
4. How to Apply It to Your Programming
Tempo is one way to manipulate the emphasis of a movement.
| Exercise | Tempo | Emphasis |
|---|---|---|
| Bench press | 3-1-X-0 | Controlled lowering, explosive pressing |
| Back squat | 4-1-1-0 | Eccentric control |
| Bicep curl | 2-0-4-0 | Slow eccentric |
| Box jump | X-0-X-0 | Explosive movement |
| Romanian deadlift | 4-1-1-0 | Eccentric control |
Tempo is written as eccentric – pause – concentric – pause. X represents moving with maximal intended speed.
5. The Biggest Takeaway
One of the biggest mistakes in resistance training is treating the lowering portion of an exercise as something you simply get through before the next repetition.
The eccentric phase is not wasted time. It is an opportunity to develop control, strength, and the ability to absorb force.
Likewise, the concentric phase is not just about completing a repetition. It is where you express force and develop the ability to overcome resistance. A well-designed program should incorporate both phases. The key is manipulating tempo, load, volume, and exercise selection based on the individual’s needs and goals.
As a strength and conditioning coach, remember: The concentric phase teaches you to produce force. The eccentric phase teaches you to control and absorb it. Both are essential to becoming a stronger, more capable athlete.
