Faster reps less effective?

[zoomer]

how fast should you do a rep? doing a fast rep is obviously easier then doing a very slow one so what is the ideal speed for gaining muscle?

Tnx

[muscleman]

Less effective for gaining muscle? Hard one to answer.

If you were to do 10 fast reps on the bench press using 80kg, and then on another day do 10 very slow reps on the bench press using 80kg, the slower reps would be more of a struggle due to there being more time under tension on the muscles.

More time under tension (TUT) does not equal more muscle gain, however. I believe the optimum range was between 30 and 45 seconds for most muscle groups. So if we were bench pressing, 10 reps with 3-4 seconds per rep would be about right.

Of course you will get many people who will say the above is garbage and to just try things out to see what works for you. I know the above to be backed up with studies into muscle hypertrophy (muscle growth), so I do believe around that figure of TUT is correct for most people.

[bagz]

bench press for instance, if your lowering/dropping the weight quickly. i actually find this harder than slowly doing reps. Not only am i pushing the weight back up but i'm also having to push up against the momentum/gravity of the weight too.

Does this make sense?

[bagz]

^^^^^^^^^^^ likely to cause injury too

[Sam]

bench press for instance, if your lowering/dropping the weight quickly. i actually find this harder than slowly doing reps. Not only am i pushing the weight back up but i'm also having to push up against the momentum/gravity of the weight too.

Does this make sense?

Interesting point, but I think you could have the eccentric phase that you are talking about the same length, just vary the concentric phase for different effects. I think the reason that you find it harder when you lower the bar quicker is because it has more momentum at the bottom and thus your muscles will have to produce more power to negate this.

[Sam]

Also zoomer, the faster the concentric phase, the more force the body has to produce. This means more motor unit recruitment, and thus more muscle is being employed every rep. Specifically fast-twitch fibres will be activated more. These have a lot more potential for growth than the slow-twitch fibres that are activated more easily. So, to tap in to the growth-potential benefits, go fast!

[muscleman]

Bagz - thats true mate, but you have to remember that if you drop the weight quickly and in a uncontrolled manner that the nagative (eccentric) phrase of the exercise is going to be less effectively (and remember, this is half the exercise!).

Sam - I sort of disagree with you, its not so much the speed but the resistance. An oly weight lifter will recruit the large motor units and fast twitch fibres, but mainly due to having to contract the muscles under a very heavy max load for a short peroid of time. If it was how fast you perform a rep then you could lift a lighter weight very quickly for 100 reps... but this wouldn't be targetting the fast twitch fibres, it would require the slower twitch endurance fibres.

There is also more to muscle hypertrophy then fibre type, such as hormone release, lactate excitation, myofibrilar hydration etc etc etc... this is why I state a TUT time of 30-45 seconds is best for hypertrophy (with a load you find yourself just able to use in that time frame).

[Sam]

Sam - I sort of disagree with you, its not so much the speed but the resistance. I agree here although I think the true barometer we're talking about is force production - but what I failed to emphasise in my earlier post is that below a certain weight threshold it's not possible to achieve maximal force production due to bar speed - this is commonly said to be at 80% of one's 1RM. I.e. despite employing a compensatory acceleration technique, due to biomechanics and the body wanting to preserve muscle integrity (this is my guess, but I know for a fact it's a true phenomenon) it wouldn't be possible to apply maximal force, i.e. less motor units are recruited and less fast twitch fibres along with it.If it was how fast you perform a rep then you could lift a lighter weight very quickly for 100 reps... but this wouldn't be targetting the fast twitch fibres, it would require the slower twitch endurance fibres.This brings me nicely to the point I was making earlier - say, for example, you could rep 80% of your 1RM in one second (concentric phase we're talking) on the bench, as force = mass times acceleration, to achieve that same force output with a weight that was a measly 10% of 1RM one would require 8 times greater acceleration, or a concentric phase time of 12.5ms! Since there is a limit on how quick any certain movement can be done, this explains why the compensatory acceleration technique doesn't fully recruit HTMU beyond a threshold.

[bagz]

muscleman wrote:
Sam - I sort of disagree with you, its not so much the speed but the resistance. I agree here although I think the true barometer we're talking about is force production - but what I failed to emphasise in my earlier post is that below a certain weight threshold it's not possible to achieve maximal force production due to bar speed - this is commonly said to be at 80% of one's 1RM. I.e. despite employing a compensatory acceleration technique, due to biomechanics and the body wanting to preserve muscle integrity (this is my guess, but I know for a fact it's a true phenomenon) it wouldn't be possible to apply maximal force, i.e. less motor units are recruited and less fast twitch fibres along with it.If it was how fast you perform a rep then you could lift a lighter weight very quickly for 100 reps... but this wouldn't be targetting the fast twitch fibres, it would require the slower twitch endurance fibres.This brings me nicely to the point I was making earlier - say, for example, you could rep 80% of your 1RM in one second (concentric phase we're talking) on the bench, as force = mass times acceleration, to achieve that same force output with a weight that was a measly 10% of 1RM one would require 8 times greater acceleration, or a concentric phase time of 12.5ms! Since there is a limit on how quick any certain movement can be done, this explains why the compensatory acceleration technique doesn't fully recruit HTMU beyond a threshold.

MM didn't say all that

i know its in italics your bit sam but its kinda hard to make out. You wouldn't be so kind as to put it in bold too so it makes a bit easier on my eyes please

[Sam]

Done now bagz, sorry about that!

[britwolf]

i like doing slow reps than faster.