The Best Lifting Tempo for Strength Gains, According to a New Study

Key Points:

A new meta-analysis compared lifting weights with a fast tempo to a slow tempo during a training program.
Lifting weights fast yielded 16.5% higher strength gains than deliberately lifting slowly.
This applies to the concentric phase. For the eccentric phase, a relatively slow and controlled tempo is recommended for both strength and muscle gains.

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Prefer listening to reading? Listen to our podcast episode about lifting tempo here:

Podcast: Lift as Fast as Possible for Better Strength Gains 🎙️

One of the most fundamental aspects of strength training is how fast you lift a weight.

Often, this takes care of itself and is probably nothing you think about.

If you’re lifting a heavy weight with maximal intent, it will move slowly.
If you’re lifting a light weight with maximal intent, it will move fast.

This is called the force-velocity relationship, and can be graphed in a curve like this:

Note that this applies to the concentric phase, where the muscles shorten and the weight is lifted up against gravity.

On the left side of the diagram, the force is high, but the lifting speed is slow even when you’re lifting as fast as you can. Here, you will recruit all of your muscles’ motor units (groups of muscle fibers working together) and stimulate them to grow stronger.
On the right side of the diagram, the lifting speed is high, but the force is low. You’ll only recruit the fastest and lowest-threshold motor units here, leaving many of your stronger muscle fibers untrained.

The force-velocity relationship has led some to believe that deliberately lifting a weight slowly will provide as potent a strength training effect as lifting the same weight as fast as possible.

This is probably not the case.

Force equals mass times acceleration:

F = ma

If you lift a given weight (m) at a low acceleration (a), the force (F) will be lower than if you lift the same weight faster or a heavier weight at the same speed.

Just because you’re intentionally decreasing acceleration doesn’t mean that mass and force go up. And if the required force to lift a weight doesn’t go up, you won’t recruit all your muscle’s motor units.

Even so, some suggest intentional slow-velocity strength training is equally or more effective than fast (or traditional) training velocities for increasing strength.

Can this really be the case, or can we refute this claim?

Luckily for us, a new meta-analysis that looked into this precise question was recently published.

Intentionally Slow Lifting Speed vs. Traditional (or Fast) Lifting

A meta-analysis published in the Journal of Strength and Conditioning Research investigated if deliberately lifting a weight slower than possible in the concentric phase affected strength gains, and if so, how.¹

The authors found 24 studies comparing strength training programs with either a lifting tempo that was:

Fast/traditional: as fast as possible, or less than 2 seconds with maximal velocity for the concentric phase.
Slow: 2 seconds or more for the concentric phase, or completed intentionally slower than the fast/traditional group.

The studies ranged from 4 to 16 weeks in duration, with an average length of 9.6 weeks.

They included 625 participants in total, of which the majority were untrained men.

What They Found

The analysis showed a significant, small effect in favor of fast or traditional training compared to intentionally slow training (effect size [ES] = 0.21, p = 0.03).

The participants who trained with a fast or traditional tempo increased their strength by 25.8%, and the intentionally slow lifting group increased their strength by 22.1%.

That is a 16.5% larger strength gain, so if the slow group gained 10 lbs in their lifts on average, the fast group gained 11.65 lbs.

In my opinion, this is pretty good. The effect size is small, but many of the best interventions we do in strength training often have small effects. Like getting enough rest between sets, eating enough protein, or taking creatine. Get enough of these details right, and it adds up.

In the sub-analyses, the authors found …

no difference between trained and untrained subjects,
no difference between older and younger (over or under 50 years of age, in this case) subjects,
but a positive effect favoring females over males.

The last point means that females saw an even greater benefit of training fast or traditionally compared to slow training. The authors point out, however, that this might have been due to details in the few studies that included females only. I haven’t checked them myself, but some of these studies supposedly used excessively light weights in the slow group, which we know is detrimental to strength gains.

Generally, men and women respond similarly to strength training, leading me to believe this was a “false” finding.

Why Is Lifting Fast Better for Strength?

When you attempt to lift a weight fast, you recruit more motor units than if you lift the same weight slowly.

And, only the motor units being recruited and experiencing mechanical tension will get stimulated to grow bigger and stronger.

This is probably why lifting a weight with a fast tempo in the concentric phase leads to better strength gains than lifting deliberately slower than you’re capable of: you’re working more of your muscle fibers.

I should emphasize that lifting fast in this case means “lifting a given weight as fast as you can.” If that weight is 80% of your 1RM or more, the weight might not actually be moving very fast (especially for really heavy weights or towards the end of the set); it just means you’re lifting it as fast as you can, and not intentionally lifting it slower.

What Goes Up Must Come Down

This meta-analysis looked at the concentric phase of strength training repetitions, which is when you lift a weight against gravity. The eccentric phase is the opposite, when you’re lowering a weight.

Barbell Bench Press — The bench press begins with an eccentric (lowering) phase and ends with a concentric (lifting) phase.

The meta showed us that you get slightly better strength gains when you’re performing the concentric phase as fast as possible – but what about the eccentric?

While I’m not aware of specific time recommendations in seconds, I do recommend that you control the eccentric.

Several studies have shown that you increase your concentric strength to an equal degree or more if you perform both concentric and eccentric muscle actions compared to only performing concentric muscle actions, even if you perform double the amount of concentric reps to equate volume.² ³ ⁴ ⁵

For muscle growth, controlling and resisting the weight in the eccentric phase seem equally potent.⁶ ⁷

I don’t think you need to lower the weight overly slowly; just don’t drop it completely. Lower it slow enough to “feel” the weight. For most exercises, this probably translates to around two seconds.

Practical Take-Aways

Here are my two recommendations if you want to optimize your lifting tempo for strength gains and muscle growth:

Lift the weight as fast as you can in the concentric phase. Heavy weights might still move slowly, the key is “as fast as you can“.
Control the weight in the eccentric phase, taking roughly two seconds to complete it. Try to “feel” the weight, and don’t drop it without resisting it.

Finally, remember that these are details. Details that can significantly benefit your training results, but details nonetheless.

The most important thing is to lift at all and try to improve a little bit each workout by adding weights, reps, or sets.

Know what a great way is to keep track of your weights and reps? Using our workout tracker.

Download StrengthLog for free with the links below:

Download StrengthLog Workout Log on App Store

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