T Nation

Value in Positive Portion?

Dr. Darden,
How much value do you place in the positive portion of a rep? If you take the practical problem of spotters out of the equation, would negative only be the way to go? And to use chins as an example instead of a 30sec positive and 30 sec negative, wouldn’t a 60sec negative be better?

1 Like

I believe you need both positive and negative work for maximum muscular growth. Research shows that the positive contributes to blood flow and the negative produces muscle fiber involvement. You require both. But I’ve noted previously that the negative phase needs to be emphasized: thus my guideline of a 2-second positive and a 4-second negative from the 1970s.

If you compared a group doing 30-second positive and 30-second negative chins to one doing 60-second negatives, who would build the most muscle? That would be interesting, and I don’t believe it has ever been done.

But what if you introduced a third chinning group. They would do 20-seconds up and 40-seconds down. Now, which of the three groups would build the most muscle?

Of course, there are other variations you might also include. Let’s give such research some thought?


Awesome answer. My thinking in a practical sense was to start using 2 up and 8 down for my reps. And aiming for 60 sec negatives on dips and chins. Which leads me to next question
If I do 2 up and 4 down for 10 reps that gives me about 60sec per set
At 2 up and 8 down how many reps should I aim for??

1 Like

Wow, 60 second negatives, it seems like 30 seconds takes forever so I can’t imagine trying for 60 seconds? That’s almost like not moving at all , ha ha .

I will add that some fairly recent research suggests that, even if similar levels of hypertrophy are produced by eccentric and concentric contractions, the effects on muscle morphology and architecture might be different.

The link which follows goes to the full text of a 2017 review of the various differences:

Xforce uses 3 sec positive and a 5 sec negative

1 Like

To be consistent in your thinking, I’d go for 6 reps. That would be 6 reps in 60 seconds.

1 Like

What about changing the middle cadence of 30-10-30 from 1-2 sec pos/2 sec neg to 2/4 (for 5 reps)? Old meets new.

1 Like

Try it and let me know your thoughts?

1 Like

Another benefit imho of for example 20 sec positive and 40 sec neg or some variation is the absence of a handoff as in neg only. If handoff is not done carefully when you climb to top portion, injuries can result as I’ve strained muscle with dips especially with added weight on belt. Plus the climb up gives momentary respite (outroading) to muscles which would not happen with 20 up 40 down or 303030 or similar variations

1 Like

I tried the middle reps of 30-10-30 for 5 reps @ 2/4 cadence.While still a physical challenge,psychologically its an improvement knowing you dont have to perform 10 reps.


I do the 2/4 cadence with the 30-10-30, and I keep my reps between 8 and 12…i did reduce the weight considerably to achieve that goal

I’ve probably beaten this to death, but I think 1 up 2 down is too fast to be smooth… and 2 up 4 down and 5 reps makes a lot of sense to me. it also depends on the movement. with nautilus pullover 1 up 2 down with the long stroke is crazy fast (I’ve tried) whereas Nautilus next gen decline press, it’s doable as that stroke is much shorter, but I like to take at least a full second for turnarounds at both ends…

30-10-30 protocol: The “10” part of a machine pullover is interesting since total movement range is around 240 degrees for me, and maybe 90 degrees on say the barbell wrist curl. So I modify this protocol for a specific exercise and its range of motion - that way I do not need to go ballistic on the pullover in the “10” part for example. On the barbell standing press for example I use a 25-10-25 protocol at the moment which has worked out well so far.


I haven’t found it to ever matter (my own experience of 30 yrs of consistent training). The key is good form and control of the exercise/weight. With that said, I like to make changes for ‘fun’ so sometimes I use a faster or slower speed.

1 Like

Thanks for all the input re cadence changes on the middle reps of 30-10-30! It’s seems interesting to stir things around a bit, but why fix something that isn’t broken?

My only issue is the original cadence of 1/2 on the middle reps. Dr Darden has later declared 1-2/2 to be ok, which enables better form and therefore suits me better.

I still believe mixed sessions in cycle is a winning strategy. The 30-10-30 and 30-30-30 complete each other very well, as I still are making strength gains in good form.

Question: When going from 1/2 to 1-2/2 the TUL may increase slightly. Does this mean I should cut the set w fewer reps? How much TUL is ok for a 30-10-30 set?

The middle 10 rep portion should be at least 30 seconds so use that as a guide if changing rep speed.


so “at least 30 seconds” as opposed to "no longer than _________ "? I kind of wondered why the variations tend to focus on 30 seconds for middle reps… or a total tul of 90 for the set? in some cases with my clients it’s over 2 minutes and occasionally as long as 3 as they are still dialing in the right weight… I’m hoping that answers to this will form part of new book… whether this 90 second tul is coincidental or actually strategic?

1 Like

10 reps of 1/2 equals 30 seconds .
Dr Darden said you should increase weight when you can perform 12 repetitions.
By “at least 30 seconds” , I mean that as the “target” minimum, just as as 10 (1/2) reps is with 30-10-30.
In the killing fat book Dr Darden recommends starting with 20 second negatives and building up to 30 second negatives rather than doing more.
Remember that 30-10-30 is not written in stone.
It is a protocol like any other that can be adapted by the coach (after feedback) to each individual.
Just a few things to consider.

1 Like

AA is right to bring this up.

The strength athletes all heavily utilize the concentric portion of resistance training. They utilize the Valsalva maneuver.
Recent studies cast doubts on the authenticity of Arthur Jones original eccentric studies. Where are his eccentric studies to examine?

The human body is perfect to work, ie. lift heavy objects. The natural movement inclinations protect and serve us well. I question anyone who preaches/promotes unnatural mechanisms to counteract human protective measures.