Split 30/30 : the classic short VMA session
Pedro · 23/08/2019 (mis à jour le 23/08/2023) · 5 min read
The 30/30 split session is one of the most used by runners. Classified as a short reference VMA session, it is also called a Vo2Max development session. Whatever the way this session is described as 30/30 split, it has many advantages. However, the classic advice we give ourselves from runner to runner are not necessarily the best... But, even if we must not abuse it as I will explain later, this 30/30 split session is really interesting to improve when we use it well.
What is the 30/30 split session?
A very simple session accessible to all runners, that's what made the 30/30 split popular. Indeed, the concept is very simple. We run 30 seconds at a fast pace and then we continue with 30 seconds of jogging. Then we use 30 seconds at a fast pace, etc. Simply repeat this sequence as many times as you can hold it without slowing down the pace.
By taking this basic definition, anyone can start the 30/30 split without complexes. We don't care about speed but about how it feels. Run fast during the 30'' fast. Feel that you are raising the cardio high while being able to trot during recovery... And especially to follow the intervals well!
How fast does his 30/30 split run?
For the more experienced runners, who know their training pace, we can specify the 30/30 split session. We will want to run 100% VMA and maximize the time we spend around the Vo2max (see why in the next paragraph). The recovery is done at a speed corresponding to half that of the fast 30″ It's slow but it doesn't mean we walk, we trot! No cardio on this session, the heart takes too long to adapt to the effort. It is therefore impossible to set his pace on this. Half of the interval will already be over by the time the cardio reaches its peak.
In the end, the goal is to be able to link as many fractions as possible in the session. 10, 15, 20 and up to 30 x 30/30 for the fittest. The respect of the rhythm is very important here to keep up for a long time. We are running at a fast pace but far from being a sprint. This corresponds to a pace that could be held up to 6' continuously if you are in shape and give it all. At this speed, we are at the maximum of what our aerobics can handle and the slightest acceleration will depend 100% on anaerobic conditions. Basically the slightest speed difference is paid in cash and will force you to shorten the session because you won't be able to keep up. That's really not the point!
READ >> READ: Running anaerobically to improve endurance
Why is the 30/30 split effective?
The 30/30 split session is one of the favourites of runners, coaches and scientists alike. There have been quite a few studies that have shown the interest of this type of session. Indeed, this session allows us to develop Vo2Max, when our oxygen consumption is at the maximum of its capacity. Running at this pace is above all about improving your neuromuscular efficiency at Vo2max. In simpler language, improve your running economy at this speed. At the same time, by running to Vo2Max, the body will learn to use oxygen better. He can't have more, so his only way to improve is to make better use of the amount he has.
The goal is therefore to run as long as possible total time at Vo2max. And clearly, the 30/30 split session is one of the best to achieve this goal. First of all, because mentally, it is a type of session that goes well. It's dynamic, you don't have time to think and say to yourself that it's hard, for example, unlike longer fractions. Then, there is a "lag" phenomenon in oxygen consumption. In a 30/30 split session, the pace makes it possible to quickly reach 100% of the VO2max. In her studies on the subject, Véronique Billat and her team have shown that 83% of the time is spent on Vo2Max during a 30/30 split! If you can make 20 fractions, it means that you pass a total of 8'20 to 100% VO2max. Not bad for a speed that you would have held 5 to 6' in continuous running!
Variants of the 30/30 split session
The most classic variant is to run your session from 30/30 split to 105% VMA. The pace is faster, so the session will be shorter and more intense. We are deliberately working here to make it much more dependent on the anaerobic process. The speed difference is about 0.5 to 1km/h depending on your level (about 10″ per kilometre). It is a small difference but it will greatly affect the fatigue generated by each of the fractions. Personally, I prefer the basic version of the 30/30 split that will really boost Vo2Max. For faster speeds, I use other types of sessions where recovery is longer than the duration of effort.
The other variants are more interesting and will be used when you are in shape. We can see the 10 to 20 x 30/30 session as the basic session to get in shape. Thereafter, it may be interesting either to continue on a 30/30 and increase the number of fractions, or to increase the duration of the fractions without changing the speed. This will allow us to go from 10 to 15 x 1'/1' at 100% VMA / Vo2Max, 6 to 10 x 2'/2' to 4 to 6 x 3'/3'. This allows you to vary from the classic 30/30 but according to the figures shown by the studies, you can continue on the 30/30 and have the same effects if you can run at 100% VMA on 25 or even 30 fractions!
Remember, in any case, the important thing is to spend as much time as possible running at this speed, whatever the form (and keeping a recovery equal to the duration of effort).
Be careful with the recovery, the 30/30 split is very tiring!
If the 30/30 split is a very effective session to progress, it is also a session that puts a lot of strain on the body. It is therefore necessary to be careful to make the best possible recovery after the session. To help you do this, I have two interesting resources. The first is the video I put below which explains what to do, right after your 30/30 split session. The second is an article in which I list 10 tips to recover in the minutes and hours following your session. You will find everything you need to put your body in the best possible conditions to recover! To read the article, click here.
Last advice to finish, as the 30/30 split session is a super intense session, I also advise you to do a good warm-up before starting it. And if you're wondering what an effective warm-up is, let's read this article. And good warm-up = good session and less risk of injury!
The 30/30 split: an ultra-efficient classic!
In the end, the 30/30 split is a classic that is likely to remain so for a long time to come! Easy to do, fun, with changes of pace every 30 seconds... It's hard but you don't see the time passing (in quotation marks!). There is no reason to deprive yourself of this type of session for those who want to improve. Be careful not to overuse it either, no more than once a week! And remember to vary and not only do 30/30 as split, the progression also involves a varied training!
And if you still have questions about the 30/30 split session, feel free to ask me in the comments, it will allow me to improve the article if there are any missing items!
