You are lifting and one bro comes in and states: “Yo bro, you lifting too fast. You gotta go slower to increase time under tension!” The next day another bro comes in: ” Yo bro, you doing it all wrong. You gotta explode up fast in order increase explosive power!” This leaves you confused and you just go home shaking your head: “WTF?”
One of the basic questions that people lifting weights ask themselves is: How fast should I lift? In order to be able to answer that question, we have to look at some basic terminology and analyze the different stages of a repetition (rep) first. Then we will go into the different arguments whether rep speed matters and if so, how fast should you perform a lift.
There are two words that are important for this discussion:
- Rep tempo: how fast you lift
- Time under tension: how long each set of reps lasts.
The individual rep can be broken down into four parts:
- The starting position: this is the position where you have the weights when you are starting the rep. For example in a dumbbell bench press, this would be when you have the upper part of your arms parallel to the floor, the elbows are bent at 90 degrees and pointing up.
- The ending position: this is the position where you finish the rep. For example in a dumbbell bench press, this would be when your arms are extended straight up in the air and you have finished the movement.
- The concentric (positive) portion of the rep: this is the lifting part of the rep and you are moving the weights from the starting position to the ending position and experiencing resistance. In a dumbbell bench press, this is when you are moving the weights up.
- The eccentric (negative) portion of the rep: this is the lowering part of the rep and you are moving the weights from the ending position back to the starting position. In a dumbbell bench press, this is when you are lowering the weights.
The speed of reps is often measured by giving 3 numbers, for example 2-1-2, meaning speed on the concentric phase, time of pause up top, speed of eccentric phase.
There are some people who argue that you should lift slow, while others argue that you should lift fast. Even scientific studies are divided on this issue, with some showing results that support the slow camp, while other results support the fast camp. Some studies even came up with mixed results. For example a study on the velocity of weight training for kayak spring performance, had one group perform lifts at a slow speed, while another group was performing lifts at a fast speed.
The conclusions were: “Slow weight training is likely to be more effective than explosive training for improving the acceleration phase of sprinting, when force is high throughout the length of the stroke. Explosive weight training may be more effective in speed maintenance, when forces are developed rapidly over a short period at the start of the stroke.” So basically, both methods were good, they just differed on which portion of the race they were more beneficial for.
The main arguments for slow lifting speed are that it lowers the risk of injury and promotes good form when lifting. This type of lifting promotes control of the weights. With slow lifting, it is argued, you also get increased extrasensory muscle control. That means that when the major muscles worked begin to get fatigued, other smaller muscles are recruited in order to do the work for them, resulting in better overall muscle efficiency and size.
A particular type of slow lifting is called super slow training and was developed by Ken Hutchins. The idea here is to keep the muscles loaded for as long as possible and thereby induce them to grow. He argues that by doing things super slowly, you are fatiguing the muscles and by doing this the body sends signals for them to grow bigger and stronger.
One of the big proponents of control and the slow negative was Mike Metzner. He was one of the most successful bodybuilders of the 1970s and built a body with very large muscles. He advocated slow controlled reps to induce muscle growth.
The main argument for lifting fast is that it allows you to lift heavier weights, which makes you stronger and builds functional muscle. In order to develop power, you should move the weights quickly. Explosive lifting leads to increased agility and power. Lifting fast is supposed to recruit the fast twitch muscle fibers more effectively.
Another proposed benefit of fast lifting are proprioceptive gains, which means better knowledge of where your body parts are in context of other parts. The body needs to respond quickly and so it learns how to do that through fast lifting. Some also argue that by lifting fast, in order to stabilize your lift, you fire up little stabilizer muscles fast as well. This then helps your body become stronger and better performing.
Both Mark Rippetoe of Starting Strength and Mehdi Hadim of Stronglifts argue for lifting fast. For them, it is the most efficient way to train. Especially Mark Rippetoe disparages the use of slow reps and is very vocal about lifting heavy and lifting fast.
What should we make of the different arguments? Sometimes, the different camps are not arguing about the same things. In order to better understand the reasoning behind some of the arguments, we need to make a distinction between powerlifting (and strength) and lifting for size and getting your muscles bigger. You can see that most people arguing for lifting fast, have the strength component in mind, while many people arguing for slow lifting have the size component in mind.
So you can argue that lifting slowly generates more size growth, while lifting fast generates more strength. However it’s not so simple. Some arguments state that the best way to achieve a particular goal are by lifting slow, while others argue that the same goal is better achieved by lifting fast. So bro science is not in agreement on the lifting speed (tempo) and neither is real science.
What should you make of all this? Lifting speed doesn’t matter, or at least it is not really a big factor. Whether you lift fast or slow is completely up to you. Try to experiment and see what is better for you and what gives you better results. Maybe try to mix it up and sometimes lift slow, while other times lift fast. I would argue that for beginners, it is better to lift slow, in order for them to learn how to lift properly. It is form that is the most important thing and not the tempo.
For gaining weight and bulking up, my reps are usually done in a mixed manner. I go slowly on the eccentric (negative) part of the lift when lowering the weight and explode back up fast on the concentric (positive) part of the lift.