Question on Isos

Hello Kelly,

What you write about increasing the TUT for certain muscle groups/joint angles makes perfect sense.

I have a few issues regarding the way ISOs are widely suggested lately (i.e. long holds of 120-180"; not referring to your example in this case):

a) TUT: why going up 20 folds? Is there a progression suggested?

b) Hypertrophy: high TUT in a stretched position will surely bring some. Unless the TUT of the stimulus is extremely low or extremely high, a muscle cell will adapt with a certain degree of hypertrophy given an intensity treshold has been surpassed. What is the experience in this regard of those that use long holds?

c) Strength: What has a 120-180" hold to do with the neural component of strength?

I hope some of you guys more versed in the DB/Schröder methodology can solve my doubts.


  1. I don’t recommend the long duration hiolds except for low level beginners. I think they’re relatively useless for anyone else.

  2. Any sort of tension will induce some hypertrophy but compared to full range or regular down and up reps the microtrauma from isometric contraction is quite a bit less. Someone going from full range reps to isos will tend to notice decreases in hypertrophy stimulation

  3. The muscular recruitment in an isometric contraction is greater than either eccentirc or concentric. Strength is largely about recruitment


Thank you for your answer.

Point b and c is debatable, but actually, I am interested in the rationale of long holds according to the DB/Schröder guys.

If I would use isometrics, I would do it the way you do.

I don’t think DB and Schroeder should be used interchangeably. The systems are nothing alike. Schroeder’s system has long duration isometrics built in, while DB’s system does not.


Thank you for clearing that up.

So the ball is to the Schröder’s guys.

Some months ago I tried to gather all the material I could on Schroeder, and also talk to a couple of guy who had met him:
1 coach and 1 football/throwing athlete.
I decided to try the long isos, since I was not training seriously for anything at that time…
the reasoning adduced by schroeder for the long Isos:

  1. position
    2)recruitment patterns (they employed active contraction of some of the lenghtening muscles)
    That was also suggested to increse rate coding., and so RFD.
  2. work capacity.
    4)…after reading papers on katsuu training protocol, I remembered Schroeder stating that, with blocked circulation, there was a favourable environment for development of type II muscle fibers
  3. can work on Fascia length

My little experiment…
Used split squats , squats and elevated push - ups 3-4 times a week…started with 60 seconds (40 on eleveated push ups), 1 set each, sometimes adding iso crunch and iso lats.
I progressed steadily…a pain insane to hold split squats 60 seconds…but eventually I reached 150 seconds, 180 seconds on squats (then started to use OHS with 20kg bar…for 60-70 seconds)…push ups to 80 seconds…

while light training, I had those results (not measured anything, since not seriously training)

  1. i’M used to have a heavy legs feeling most of the days, but after some training…never hd such light and fresch legs in my life!
  2. flexibility…I gained some amazing feats, even with cold muscles…I’m not particularly flexible…but neither stiff…cold, I can lift straight leg up to low chest maybe…but after some sessions, I could get it past my head stannding…and cold!
  3. running…absolutely able to be relaxed, foot stepping over, hips very loose…
  4. bench
    press…while not training, 3 weeks after I managed to increase seriously number of reps performed and wweight used…

I also had 2 sprinters (100m and 400m) follow the leg part 3/w after training…, for 60-90" on splits, and 150 180 on squats…
1 had some minor hams issue, and he got better , 1 was very stiff after training…and had some benefit…

Sorry , in another month I would have conduted more scientifi tests…( squats, VJ, alternate bounds, 30m and so on…), but was very busy…and preparing to spend some time in Brazil:)…and mayb t, if training seriously, I’d have nevere tried them…

Did you ever use any weights on the split squats, also, did you ever perform any actual split squat or squat reps mixed in with the isos?


Thank you for your informative post.

The rationale is a bit blurry, still.

The effects you had are very interesting.

I must definetely try them myself, I’ll see if I can add them to my current program.

Seeing that Schroeder’s system is based on a completely different concept of training (e.g. evolving the body with every workout - hence EvoSport) - based on the bulgarian methods - compared to what we are used to you really need to look at the system as a whole rather than try and take bits from it and see these in isolation. Also he uses many different kind of methodics not simply Iso holds but subtle variations. If you really want to learn the system I suggest training with him for a year or two - IF you can stand it!

This is normal if the athletes cheat and use one HS more than the other. You get pain behind the knee. Doing the exercise with proper form will prevent this.

A coach I know worked witha guy who previous tried to join that group. This athlete was told before he could join the group, he had to hold a iso-lunge for 45 minutes. Until then, he could workout with the wives and girlfriends.

I also heard other horror stories with Adam during his HS days before he could join (fecal measurements) :eek:

i hope ur joking

These are stories told from people who wouldn’t lie.

In Freak of Training DVD, Adam and Jay talk about “things adam had to do before Jay would work with him” but never said what it was.

I’ve been training exclusivey with isos since beginning of February under Pakewi’s advice, (recovering from several injuries that are a result of 4 years of overtaining).
The first 3 weeks or so, I also incorporated sprints on iso-off days, and having not trained on the track since a whileee ago (New Years time) (>injuries one after another, all my previous overtraining hit me in loads this year), those sprints felt surprizingly great, in the sense that my overall form felt a LOT more clean than what it did even when I used to run/sprint daily. (Now I don’t even sprint, because another problem occured :rolleyes: )

I perform both long holds (a number of different exercises for as long as 5minute holds each >I am able to hold all exercises for that long by now) and iso reps as well. Only I wouldn’t like to post details of the program, as it is not my inspiration to share.

The interesting part is that me being a trainaholic, only doing this program so far leaves me “satisfied”. And I like the feeling of my body more than when I used to be a weightroom rat (I could squat 8 reps of 235lbs :o > I’ve given up weights completely since January). The muscles feel denser and never “heavy”, and I do feel trained.

I’m curious to see where this takes me!
One thing for sure is that my mental training-patience has vasty increased (sometimes I do iso sessions twice a day, and each sessions lasts about an hour), which is a lot less time than what my track sessions used to be, only you feel every second of it.

I still do not know all the intricacies, but I think also the key is to perform the “microcontractions”, during Isos…
If we have to believe to schroeder’s, then we have to try to get over 3 minutes, since classical parameters for ISOS will work other areas…
I agree with Stefanie, the feeling of limb freedom during running is unbelievable…I’m re-starting to incorporate them, but this time as an adjunct to training at the end…
what amazes is the adaptation of your body…first session you die in 60 seconds…2 weeks later you can smoke 150…or more on spllits…
Sprinterouge, I broke my laptop, so lost many contacts on the email…can you re send me your contacts in Pm.?


I am a big fan of it being in everyone’s program to some extent. It can be as simple as starting with a push-up hold and a bulgarian squat hold. They key is to not overthink it or make it magical. It’s a training method.

Also…you need a good sensibility, knowing correct efforts, contractions and so on…
while Isos can be mantained, progression would emply:
ISOS-Drops-Reactive methods…

Hello Eros,

Any of my email addresses you find on the internet are good.

Tomorrow I will start with 60" Iso lunges and progress them for the next 6 weeks (only once a week).

I’ve only used bw isos 4 times (twice in the last two weeks) and I can’t imagine going for 5 minutes or whatever. I have only done squat, lunge and good morning holds. From what I can tell, they do serve a purpose as part of a training plan but are not a plan in themselves. I have just used them after my tempo workouts and done holds between 45 and 90 seconds wouldn’t go past 120. I feel like they have helped me with my active flexibility, recovery and I feel more warmed up or ready to go when I’m not training, as in warming up for stuff has been easier and quicker.

I remember reading somewhere that Jay said they are very taxing on the sympathetic nervous system. I don’t know if there’s any truth behind that, but I have noticed that immediately after, I feel a lot more calm and mellow, which is why use them as part of my cool down.

Have you ever tried it? > or actually witnessed people try it as an exclusive plan that failed? (It’s not a combative question ,I’m only curious).

what if any role do you think iso’s could / should play for people who’s lower back rounds in the squat?