Should athletes lift weights fast or slow? An interesting subject that may well be very complex but also as simple as; “do which you prefer”.
Sports scientists have great arguments both for and against lifting a weight with a fast contraction. This is a brief look at some of the science and reasons for each side of the coin.
The Lift fast Camp:
The old saying goes that you must lift fast to be fast.
Science shows us that the nervous system ultimately controls the behavior of the attached muscles i.e. a fast twitch motor unit creates bigger muscle fibres, better power output, less endurance and faster, stronger contractions; all of which allow for a fast athlete. Many will cry out that MU (motor units) don’t create muscle fibre characteristics BUT they do. Studies show that if you…
innervate a previously slow twitch muscle fibre with a fast twitch motor unit then the fibres will change characteristics heavily in favour of fast twitch. The CNS rules all.
So the fast camp want to promote fast characteristics from the get go in all muscle fibres by trying to convince the slow MU that they are actually fast and the fast MU to become faster. Which is right…and wrong.
Rate of force development (RFD) is another reason often cited for fast lifting. RFD refers, as you may expect, to the speed at which you create force. This obviously has a massive impact in sports; two athletes can run 20mph top speed but one gets there in nine seconds and the other in 10….which one wins the ball, scores the touchdown/try/goal and gets the trophy? Not the one who got there slowest. RFD is improved through faster lifting speeds. Which is right and wrong.
Tension is another subject that comes up when talking about speed of movement. It is thought that higher tensions are a good thing when it comes to strength, power and hypertrophy training so the fast lifting camp advise that the faster you lift a weight the greater the tension across the muscle. Which is right…and wrong.
That is the basic premise behind the argument for faster lifting speeds, now to the slower lifting speed camp.
The Lift Slow Camp:
The common theme here is lifting slow is safer.
Force plates are devices that get used frequently in the sports science world and are basically an advanced weighing scale attached to a computer. A person stands on a plate that measures the forces generated. These show how much force is generated in differing movements and it has been shown time again that slower movements distribute a more even force with less peak forces through the skeleton. Hence the safety concept. Which is right and wrong.
Higher forces which are largely unknown to the lifter are potentially more dangerous due to the sudden nature in which they are experienced and they also appear to offload the working muscles due to momentum in certain parts of a movement. BUT they can be effective at preparing contact athletes to absorb high impact forces.
So slow lifting can be considered safer and any athlete that gets injured during a strength training session is an athlete that cant partake in their sport which makes them a non athlete for as long as the injury persists. Always bad. Slow lifting argues that an athlete should prepare for the impacts of their sport by training their sport and not in the weight room.
And the Science Says…
It depends entirely on your goal.
A bodybuilder has no need to concern themselves with athletic performance so speed is at the trainees preference.
An explosive athlete however cannot afford to sacrifice speed for bulk most of the time.
So far as I can find in the research speed of a lift isn’t what is responsible for the increase in RFD (rate of force development), it is the attempt to move fast which is of more importance.
Take for example the speed of movement in a 100m sprint versus the speed of movement in the lifting phase of a deadlift/squat or snatch. The sprint will see a sprinter moving faster but the slower movements of the weight training still help to enhance speed so long as the lifter try’s to move the load quickly… in spite of the actual speed. The attempt to move a heavy load quickly (when in fact it moves slowly) still requires maximal effort from the involved muscle and thus nervous system, which ultimately controls speed.
Slow lifting argues the MU characteristic point in as much as it isn’t the actual speed of movement that activates the fast twitch MU but the attempt to move quickly, meaning a heavy weight that moves really slowly despite your best efforts to move quickly has the same effect as a lighter weight moved far faster.
RFD is both general and specific so both camps have a point. Lifting fast will help you increase RFD in those muscles involved for both that specific movement and any movement that involves those muscles.
Actual speed of lift may not be as important as once believed
Attempt to move quickly is a key factor in RFD
If you enjoy lifting quickly and are resistant to cheating techniques and injury then go for it, if you prefer the smoother and slower continued tension then do that. The likelihood of your lifting speed being the deciding factor in your sporting success is small.
As a Personal Trainer here in Epsom I use a variety of lifting techniques with myself and the athletes that train with me depending on advancement, personal preference and individual bio-mechanics.
Realistically your speeds will vary to a large degree in your training sessions and if the actual speed of movement were a deciding factor then athletes would avoid lifting weights all together.
When I/a client want to build muscle I find that varying rep speed throughout a set is far more beneficial to getting the most from a set.
When we want to increase the amount of weight lifted in a specific lift we train that lift with as much speed as possible and learn of to continually (grind if its a weight lifting movement) apply that effort for relatively long periods of time.
Watch out for videos detailing different methods.