Karl’s Introduction to Pumping - Part 2 - Interval Pumping and Rapid Interval Pumping (RIP) Explained - Pros and Cons - Equipment - Routines
Welcome to the second part of my introduction to pumping. In this one, I will be looking at Interval Pumping, Rapid Interval Pumping (RIP), Milking for erection quality, recovery and shape retention, give you an overview of different electric Auto-Pumps on the market, and also suggest some routines. Let's jump right in!
(Intermediate) Interval Pumping
Many of the same recommendations I gave in part 1 about static pumping also apply for interval pumping, such as equipment, safety precautions, warm-up, etc. So I will just explain what interval pumping is, and any benefits it might have compared to static pumping, and give you a simple beginner-intermediate-advanced routine progression.
Definition: Since PE is a field where we are writing the book ourselves, I will take the liberty of defining interval pumping as the practice of pumping in sets of 1-2 minutes or thereabouts (Yes, I am aware this creates a zone of vagueness between 2-5 minute intervals which are neither really interval pumping nor static sets - this is on purpose).
Interval pumping introduces relatively frequent rest periods between pressurised sets, where fluid accumulated beneath the skin gets a chance to be reabsorbed by the blood or dealt with by the lymphatic system. Pound for pound (or minute for minute), interval pumping tends to result in less edema than static pressure pumping. People who do 1-2 minute intervals often use pornography during their sessions and take the cylinder off between each set to stimulate themselves to try and maintain an erection, and also to allow some edema to drain more easily.
Debunking the misconception
They do so sometimes in the erroneous belief that staying erect means erection pressure and the vacuum pressure are fully additive so that an internal penile pressure of +5 inHg and external vacuum of -8 inHg will result in a 14 inHg pressure differential over the tunica. This is not entirely correct - or rather, it is entirely true that one's arterial pressure and the negative pressure of the vacuum are additive in this manner, but this is equally true for when you start pumping flaccid**.** Once you apply a vacuum and your penis fills with blood, if you give it a good kegel or two the internal pressure it will take on is your arterial pressure anyway - the vacuum will dilate the deep arteries inside your CC and this will pressurise your penis from within as if you were naturally erect. Starting pumping flaccid vs erect makes much, much less of a difference than people think - and they get it wrong because intuition is sometimes not the best guide to understanding a phenomenon. My suggestion: Don’t fret it. If you prefer pumping without using porn or masturbating you don't need to feel you have to because some misinformed PE influencer told you that you have to start erect.
Benefits of Interval Pumping
Interval pumping has the benefit of causing multiple stretch-events. Such events are a mechanotransduction-trigger and also represent a chance for collagen fibrils in the tunica to slip and slide. In a 30 minute session with 2 minute intervals and 1 minute breaks you will get 20 minutes under pressure and 10 such “stretch-events”. Reduce to 1 minute sets and 30 seconds of rest you will get 20 minutes under tension and 20 stretch-events. For a more in-dept explanation of mechanotransduction-mediated release of matrix metalloproteinase, have a look at my blog article about how PE actually works: https://blog.fenrirgym.com/how-does-penis-enlargement-actually-work-a-somewhat-deep-dive-e272de1eb43d
Mechanotransduction. From Nature Reviews Molecular Cell Biology volume 24 (2023)
As a rule, people tend to think interval pumping results in less edema than static pumping. This is my experience as well, but not everyone responds the same. Try it - I think you will like it. Especially if you take the cylinder off and stimulate yourself between each set - it makes routines fun - wanking your pumped D feels good in the hand; almost addictively so. (But there too people will have a difference of opinion; for about 2-8% of men, porn use can become a problem and even result in erectile dysfunction with their partners - similar to alcohol, where not all become alcoholics but some do. Wanking with temp-gains can make some men feel size dysphoria when they are with a partner and haven't pumped before.)
Equipment
TotalMan's OEM-clone of a LeLuv Magna Pro
For interval pumping you can use a cheap hand pump, but many who like the technique prefer to use an electric auto-pump of some kind. The LeLuv Magna Pro is a popular model, but many vendors sell OEM versions under different brand names, or even no-name versions of the same device or clones thereof. I will have some more detailed equipment recommendations after I have discussed rapid interval pumping and why I prefer that to normal interval pumping.
Beginner, Intermediate, and Advanced Interval Pumping Routines
Interval Pumping Routines should progress in intensity as users become more conditioned:
- Beginner Routine:
- Pressure: -5 to -7 inHg. Gradually increase the pressure during the session.
- Duration: 15–20 minutes. 2 minutes on, 1 minute off for massage and/or masturbation. No “sets” - just keep this cycle up the whole time.
- Frequency: Anything from 3–4 sessions per week all the way up to 14 sessions (AM + PM every day).
- Intermediate Routine:
- Pressure: -7 to -10 inHg. Gradually increase the pressure during the session.
- Duration: 15–25 minutes. 1 minute on, 30 seconds off for massage and/or masturbation.
- Frequency: Anything from 4–5 sessions per week all the way up to 14 sessions (AM + PM every day).
- Advanced Routine:
- Pressure: -10 to -12.5 inHg. Gradually increase the pressure during the session.
- Duration: 20–30 minutes. 1 minute on, 30 seconds off for massage and/or masturbation.
- Frequency: Anything from 5–6 sessions per week all the way up to 14 sessions (AM + PM every day). You can even add a session mid-day during lunch.
Don’t rush the progression from beginner to intermediate to advanced protocols. If working between -7 and -10 inHg gives you plenty of expansion (6-12%) with minimal edema there is no reason to progress further with the pressures.
EDIT: Two people have asked already, so I will make this point here instead of answering it more times: It's perfectly fine to do breaks between intervals that are as short as 3-5 seconds too. Some auto-pumps have that as their default, and there is nothing wrong with it. It will allow less time for edema to recede, and intervals that are 1-3 minutes long do tend to give more edema than the next method I will describe (RIP), but if this is what your pump does, and the edema you get is within what you think is tolerable, don't fret it.
Rapid Interval Pumping - RIP
The same general equipment and safety recommendations apply for RIP as for interval and static pumping. Use an oversized cylinder and pump pad or, failing that, a 15-20% upsized cylinder only for good comfort. However, because RIP will generally be done at higher vacuum pressures than static or 'vanilla' interval pumping, it becomes more important that the cylinder should have a shape which is gentle on your dorsal nerve insertions at the base of your penis; more pressure will be applied there, so a sharp transition from flange to cylinder will be a bit dangerous.
With Rapid Interval Pumping, you use pressure cycles that are anything from just a few seconds long to about 15-20 seconds long, and the downtime between each cycle should be from 1-5 seconds. The raison d’etre of RIP is multifaceted;
First, the many rapid intervals mean sessions will result in many, many stretch events - i.e. dynamic events which give opportunity for fibril slippage in the tunica and also stimulate fibroblasts to release matrix metalloproteinase to soften the collagen fibres by snipping molecular bonds. It also stimulates them to repair and lay down more collagen. Mechanotransduction-induced fibroblast activity, in other words. Since you get a great many more stretch events, you will get more stimulus - that’s the theory. And RIP tends to result in actually better expansion, so the theory works in practice.
Note: It’s not that normal static pumping or normal interval pumping does not result in MMP release; it’s just that RIP gives you more stretch events, and allows you to work with more intensity, which pulls on two of the “levers” for MMP production; you have Frequency (number of stretch events), Duration (total time under tension), Intensity (how hard you stretch the tissue), and also Directionality (how many directions your fibroblasts are stretched). The parameters in bold are where RIP will outstrip the other varieties of pumping. Is it a huge difference? We lack the data to know for sure, and with time I hope we can gather more community data from hundreds of pumpers using different protocols. Until then, I tentatively believe it makes a pretty significant difference. Enough that I go all-in on RIP.
Second, the fact that you are doing such short intervals allows frequent opportunities for fluid to be reabsorbed and for some reason seems to protect really well from blisters. This allows each interval to be done at higher pressure without increasing the blister risk compared to lower pressure pumping with longer sets.
Working at higher pressures allows you to reach higher peak stretching forces in the tunica, both longitudinally and circumferentially (girthwise). Both of these forces scale in a linear fashion with pressure, so -17 inHg gives exactly 2x as much force as -8.5 inHg, in both directions. Simply put, this allows you to work with the principle of progressive overload in a manner that static sets or longer intervals will not allow due to their greater tendency to cause blisters.
Risks?
Is this risk free? Of course not. The tunica albuginea is strong enough that it can handle pressures close to total vacuum (if your penis is in good shape to begin with and does not have prior damage causing weak spots). However, your capillaries will not enjoy these pressures and rapid changes, so the method will tend to cause redness and in some cases bruising. This means its propensity to cause discolouration will be slightly higher than in other methods of pumping simply because we are using higher pressures and might be transitioning faster - but that is something that you can treat with 5% lugol's iodine solution to clear up. I have seen occasional reports of small bleeds from the urethra or meatus, but I have seen the same kind of reports from vacuum hanging/extending and actually from pumping at lower pressures as well. I have personally done over 200 RIP sessions where the final set has been at -17 inHg for 5 minutes of rapid intervals, and I have not had a single blister. I do get plenty of swelling around the frenulum and foreskin area, however. But that is not an injury, just an inconvenience.
Penile Health Benefits?
RIP is the pumping method that gives me the best expansion in the least amount of time, and I also think it has other benefits. In this post I look at the benefits of oxygenating the penile endothelium inside the corpora cavernosa - an anti-fibrotic, rejuvenating treatment which functions a lot like your nocturnal erections, only more so: https://www.reddit.com/r/TheScienceOfPE/comments/1i0lnsg/the_role_of_vegf_and_strategic_ischemia_in/
In this post about nocturnal erections, I write about how rapid interval pumping or milking mimic the mechanisms that make nocturnal erections so beneficial:
These benefits bring us to the next interval pumping method, which seeks to maximise oxygenation and stretch-events inside the corpora cavernosa, and which is also an excellent method for ‘shape retention’ - which is sometimes called doing “feeder sessions”.
Milking - for EQ, Recovery, and Shape Retention:
To improve my erection quality I sometimes do sessions of what I call milking, where I use less pressure than in RIP performed for expansion, and even shorter intervals. This is sometimes called dynamic pumping or angio-pumping. The aim is to remain fully flaccid and repeatedly draw in fresh blood. I do 3-5 seconds on and 1-2 seconds off, and sessions can be anything from 10 - 30 minutes. This does wonders for nocturnal erections and hardness - you can really feel it rejuvenating the tissues. The pressures I use for milking will be in the range that I consider “low”: -4 inHg up to about -7 - 8 inHg or so. I will not give a detailed routine description for milking beyond this. A lot of 10 minute sessions thrown in for shape retentions, or a few sessions here and there just for penile health. Pressures are not all that important - just don’t go so high that your penis does not deflate well during the off interval.
Here is an example of very rapid milking at low pressure (warning, my dick):
https://www.redgifs.com/watch/frivolousicydwarfmongoose
I suggest using more pressure, longer intervals, than what is shown here. Also, try and remain flaccid.
Shape retention - acutely and also on longer time scales
The purpose of milking is not just penile health and recovery, it’s also a great method of shape retention. If you do short sessions of milking here and there during the day, this not only gives you a temporary increase of penile volume - the stretching stimulus also up-regulates the enzymes nNOSs and eNOS and therefore NO production, which will tend to make your flaccid size tend to stick around for longer. nNOS+eNOS > NO > cGMP > vasodilation is the short and simple explanation of the process (see our wiki for more details).
Why you should not do milking during your weeks off:
On “off” weeks where I want to allow MMP levels to go down and allow my fibroblasts to repair the tunica and lay down more collagen, I tend to either avoid milking and do static sets at very low pressure instead to remain tumescent, or do milking at super low pressure -4 - 5 inHg. The reason you want MMP levels to go down during your weeks off is that elevated MMP suppresses collagen synthesis. And while collagen synthesis can be negative when it causes our tunica to grow stronger, it’s also needed because we want material to grow with and to remodel. We should therefore cycle remodeling and collagen synthesis by periodisation of PE.
Beginner, Intermediate, and Advanced RIP Routines
Rapid Interval Pumping Routines should progress in intensity as users become more conditioned:
- Beginner Routine:
- Pressure: -7 to -10 inHg. Gradually increase the pressure during the session.
- Duration: 10–20 minutes. 15 seconds on, 3 seconds off.
- Frequency: Anything from 3–4 sessions per week all the way up to 14 sessions (AM + PM every day).
- Intermediate Routine:
- Pressure: -9 to -14 inHg. Gradually increase the pressure during the session.
- Duration: 15–20 minutes. 15 seconds on, 3 seconds off.
- Frequency: Anything from 4–5 sessions per week all the way up to 14 sessions (AM + PM every day).
- Advanced Routine:
- Pressure: -10 to -17 inHg (some use more). Gradually increase the pressure during the session.
- Duration: 20–25 minutes. 12 seconds on, 3 seconds off.
- Frequency: Anything from 5–6 sessions per week all the way up to 14 sessions (AM + PM every day).
As with interval pumping, you should not be in a rush to increase the working pressures. If beginner routine pressures and times give you good expansion (106% or more increase in erect girth with a cock ring on), there is no reason to move on to the next level. The longer you can stay at lower pressures, the better, since it staves off strength adaptation and the need for decons.
Equipment for RIP (and Interval Pumping too)
I imagine there are men who are real chads and who could use a hand pump to do rapid intervals in this manner to grow their forearms. I’m an old man and would develop carpal tunnel syndrome or tennis elbow in a few days of attempting it. Most guys will need some kind of electric pump to do the work for them.
A LeLuv Magna Pro+ can serve the purpose of RIP-aid rather well, but the user interface is not intuitive, it’s quite noisy, and it’s also rather slow. A benefit is that it is small and portable and can easily be stashed away discreetly.
LeLuv “Smart iPump LCD - also sold as an OEM product by other brands
Many auto-pumps, such as the one sold by PMP and Massive Novelties, simply don’t have the ability to do sets shorter than 1 minutes, so they are not an option for RIP unless you do a little manual work-around: If you set them to hold static pressure, and splice in a normal pump handle with gauge to serve as a pressure release button, you can actually manually drop the pressure every 12 or 15 seconds. The pump will automatically pump back up again. The same thing goes for the other LeLuv pumps, of course. The LeLuv model “Smart iPump LCD” looks like a decent cheap option for normal Interval Pumping with 1-2 minute intervals, and if you want to do RIP with it, you can splice in a pump handle.
Goat Milker pump with a spliced in manual pump - simple and effective combo
For several months, I used a “Goat Milker” pump from Amazon (they’re also available on AliExpress for instance). That kind of pump is pretty cheap, and they’re also very strong and fast and make a rather discreet chuffing sound compared to impeller-based pumps such as the LeLuv auto-pumps. The drawback is that there is no interval automation at all, so you just use the pump to pull a static vacuum, and then you manually drop the pressure with a spliced-in handle with a pressure gauge. Because the pump lacks its own pressure gauge and release button, you are reliant on the ones on the handle. It’s a cheap and effective setup, but not so easy to stash away between sessions.
Elite Pump Pro - the current G.O.A.T of pumps
For a really premium experience at a cost, you have my favourite method, which is using an Elite Pump (pro model optional) from elitemaletraining.com which is where my buddy Cowabunga aka u/Dry_Jackfruit3577 sells this final evolution of what was previously known as “the butt- and breast pump” or the “custom diy butt pump” and similar names. It’s a custom version of a pump that was originally made for women who want to enlarge their breasts and butts. Many features have been added, such as making it programmable, extending possible interval times, giving it a manual pressure release button for safety, and in the Pro-model also allowing it to drop not to zero in each off cycle but instead down to about -5 inHg, and also a switched pass-through for a vibrator in case you wish to emulate the PhalBack vibra-pumping protocol.
I won’t pretend to be neutral here; I’ve been intimately involved with recommending the specs for this machine, an active participant on the pumping discord, Cowabunga and I are buddies and I have received a free product sample - so I am as biased as can be when I say this is the absolute Rolls Royce of interval pumping tools. I have reviewed it in full here: https://www.reddit.com/r/TheScienceOfPE/comments/1ig9wnq/a_very_biased_review_elite_pump_pro_the_goat_of/
The 'vanilla' Butt-and-Breast Pump does an excellent job, but offers lower value for money
If you want a cheaper version and can live with intervals not being longer than 9.5 seconds, a slow seeping leak, and a pump that has no useful presets or the ability to store your own, then the original butt-and-breast pump from Amazon, Aliexpress, Mychway or other webshops is an excellent alternative. I used such a pump for quite a while and was very happy with it and will not hesitate to recommend it over any of the cheaper interval pumps on the market. Even this simpler model is a LeLuv, iPump, and ‘Goat Milker’ killer for sure.
For the sake of completeness, I should mention the DP-4000 pump from CTC, which was once the #1 programmable pump on the market - the absolute king of the hill. It’s limited to -15 inHg at the top end, and is weaker and slower than a butt-and-breast pump. It also requires connection to a Windows PC, has software that was last updated in 2012, and costs $500 + shipping. CTC have other interesting pumps, but the DP-4000 has been thoroughly vanquished and does not offer a good value proposition when there are cheaper models that are better. The king is dead, long live the new king.
With this, Part 2 of my series on pumping has come to an end. If it was of value to you, please give it an upvote or leave a comment so that the algorithm picks it up and shows it to more people.
In Part 3 I will discuss what I call “Pumping Adjuvants” - things that could enhance the effectiveness of pumping routines and sessions; IR heat, Vibration, Warm-ups with Bundled work, etc. I will also be debunking some common myths, such as the often repeated myth that water pumping would give less edema or more expansion than air pumping due to some magical property of water. I will also write about the oft-maligned practice of length pumping and debunk the idea that it’s not a valid method.