Slow twitch fibers got a bad reputation in the power world. Slower, weaker… what self-respecting lifter or wrestler would want to train them? Yet cutting-edge Russian research tells us that every type of athlete, from marathoner to powerlifter, has a lot to gain from training slow twitch fibers.
First, I will talk about the needs of powerlifters and others who pursue strength events in which the speed of contraction does not matter: Iron Maiden/Beast Tamer Challenge, the front lever, the iron cross, etc. Then we will deal with power athletes like Olympic lifters and sprinters, and finally with a wide spectrum of athletes needing endurance, from fighters to ultra-endurance runners.
I. Slow Fiber Hypertrophy for Absolute Strength
While it is true that slow twitch (ST) fibers do not get as thick as their fast twitch (FT) brothers, we have known since the sixties that per square inch of cross section, they are just as strong. In other words, two finger-thick bunches of fibers, fast and slow, are equally strong. Sure it takes a higher number of thinner fibers to make up that bunch, but why would that matter?
Consider the study by Selouyanov in which experienced athletes did very light and slow squats* and increased their 1RM by 25.6% in six weeks. Are you interested now? Not surprisingly, there are elite Russian powerlifters such as Dmitry Kasatov and Alexander Grachev who use state of the art ST fiber hypertrophy protocols as an integral part of their training.
Should you do it too? Perhaps. There are two downsides:
- First, something has got to give. Your time is limited and so are the resources of your endocrine system. You will have to introduce ST hypertrophy training at the expense of something else — and your programming will greatly increase in complexity.*
- Second, many 1RM guys and gals simply despise slow, “go for the burn” reps (understandably).
There are upsides too. A high-mileage lifter is able to dramatically reduce his heavy training mostly to the practice of the competition lifts while taking care of hypertrophy with light ST exercises. Reportedly, this is what great Vasily Alexeev did for his back. His back problems prevented him from doing heavy deadlifts (snatch and clean pulls). So he developed a secret variation of the back hyper* and kicked everyone out of the gym and locked the door when he did it.
Another upside is maximizing one’s muscular development — if this is your goal. You are a heavyweight lifter, a football lineman, a power bodybuilder.
If you need to watch your weight, you still could use this tactic locally. E.g., if your goal is to improve a press — kettlebell or barbell military press, bench press, handstand or one-arm push-up — adding a triceps ST hypertrophy protocol to your regimen is neither going to tip the scale, nor make your training too complex or draining.* The same applies to a grip master pumping up his forearms.
If you fancy yourself a “hard gainer” trying to bulk up, I anticipate your idea to do this type of training exclusively. When it comes to your upper body, don’t even think about it! An average person’s upper body muscles are 70% fast twitch. Even if you are far the other way, you are still loaded with FT fibers and they have a much greater potential for growth. Combine FT and ST hypertrophy training perhaps, but do not go exclusively ST.
For the legs it may not be a bad idea. They have a fifty-fity average ST/FT ratio and you might be skewed far into the ST. Your answer could be training like an injured lifter — moderately heavy singles, doubles, and triples to address the neural and psychological components of strength plus light ST hypertrophy work.
II. Slow Fiber Hypertrophy for Power Athletes
Since fast fibers contract faster than the slow ones, it does not seem to be a good idea on the surface. Yet, according to maverick Russian professor Victor Selouyanov, you would be making a grave mistake:
“[Although] maximal speed of ST and FT muscle fibers differs by 20-40%, the contraction speed in real athletic actions does not exceed 50% of the maximal contraction speed. Thus an increase in strength of the ST fibers increases power and speed practically in all types of athletic activity. Even in a sprint.”
Selouyanov and Turaev established that 50% of the sprinting power comes from slow fibers! Then they subjected a group of experienced sprinters to a leg ST hypertrophy regimen. Their 100m times improved from 10.9 seconds to 10.7 seconds. In other experiments, Seluyanov increased the athletes’ standing jumps through ST hypertrophy.
The pros and cons of introducing slow fiber hypertrophy training into your regimen are the same as for powerlifters and Iron Maidens.
III. Slow Fiber Hypertrophy for Endurance Athletes
A short answer is, absolutely! One’s endurance, be it in an MMA fight or in a marathon run, is dependent on the mitochondria that enable the muscle to use oxygen.* And slow fibers, unlike fast ones, come pre-equipped with mitochondria. It will be a game changer for your “conditioning.” For instance, in another study by Selouyanov, eight weeks of ST squats upped the anaerobic threshold by 20%.
*Stand by for a series of articles that will expand on the topics I have marked with an asterisk, as well as detailed training protocols. A heads up: slow twitch fiber hypertrophy training is done very differently from what you might expect. So do not rush for the “burn” until you read the directions.