When it comes to lifting weights, one of the most common debates is whether slower, longer reps are actually better for building strength and muscle. To understand this, it helps to first break down any lift into three distinct phases, the eccentric, amortization, and concentric phases. Take the bench press as an example. The eccentric phase is when you lower the bar toward your chest. The amortization phase is the brief moment at the bottom when the bar pauses and energy is stored in the muscles and connective tissue. Finally, the concentric phase is when you push the bar back up to the starting position, generating force to move the weight.
The idea of moving the weight slowly comes from the concept of time under tension, which emphasizes keeping the muscle under load for longer periods to stimulate growth. While mechanical tension is an important factor in building muscle, it is only one part of the equation. Overall rep volume and controlled muscle damage are also key. Slowing down your reps can make each individual repetition feel harder, but it can also reduce the total number of reps you complete by the end of a set, potentially limiting overall stimulus for strength and growth.
Now to understand why faster reps can be beneficial, we have to consider the physics of the movement. Force is calculated as F = M × A, where F is force, M is mass, and A is acceleration. To lift more weight, we want to maximize force, and one of the easiest ways to do that is by increasing acceleration.
Ground reaction forces also play a role. This is the physics concept of every action, there is an equal and opposite reaction. If you lower a weight faster, more force is transmitted into the ground, and that force pushes back against your body, helping you drive the weight upward. Think of it like placing a rock gently on a sheet of ice versus throwing it. The faster the rock moves, the more likely it is to break through the ice. Lifting weights follows the same principle. Moving with some speed allows you to generate more force and lift heavier loads, which ultimately drives strength gains.
To truly answer the question of whether faster or slower reps are better, we have to look at context. There are legitimate reasons to use slower, more controlled movements, particularly during the eccentric phase. Slowing down while lowering the weight forces your muscles to lengthen under tension, which is excellent for tissue remodeling, building resilience, and supporting injury rehabilitation. This is especially relevant in our ICBC active rehabilitation programs, where controlled eccentric loading helps members safely rebuild strength after injury. It is also a useful tool in small group personal training or personal training sessions at AIM Athletic, when the goal is technique mastery, joint control, or addressing movement limitations. Even in off-season hockey training, slow eccentrics can help improve muscular durability and prepare athletes to handle the unpredictable forces of the game.
In the end, there is no one-size-fits-all answer. Fast, powerful reps are key for building maximal strength and force production, while slow, controlled reps have their place for tissue health, rehab, and technical refinement. Understanding when and why to use each approach can help you train smarter, get stronger, and move better, whether your goal is dominating on the ice, improving general fitness, or recovering from an injury.
You've got the info now it's time to take AIM,
.webp)
.webp)
.webp)
.webp)
