Recently I started a new part-time job at a small, private, fitness studio that does "slow motion" or "superslow" training. (My certification is from NASM, and I am also working in a traditional health club doing 60 minutes of functional training sessions.) It is a low stress, well paying job, but I am conflicted about the training method. Superslow utilizes expensive, specially designed selectorized equipment (leg curl, leg press, abductor/adductor, chest press, assisted dip/chin, lat. raise, triceps ext., seated row, lumbar ext. and abs). The tempo is supposedly a 10 second eccentric and 10 second concentric phase, though most people are a bit faster. Reps are not counted; instead, a stopwatch is used, striving for approximately 2 minutes and 30 seconds of time per exercise. If it is too easy, than the weight is increased the following workout, and the clients are closely watched for signs of "failure." Each workout is 20 to 30 minutes in length and one set per exercise. Keep in mind that most of the clientele are also regular hikers, bikers, yoga enthusiasts, Pilates practitioners and/or spinners, and they all seem to be believers in the method. My question is, for a person who does NOT want to build muscle mass, wouldn't this type of workout be inappropriate due to the length of the time under tension?
We do get to throw in some "variety work" (i.e. ball squats, lunges, floor abs, free weights, etc. here and there), but due to the 20-minute limit, it's generally pretty minimal. I also do not get to do the initial assessments myself, which puts me at a disadvantage when it comes to choosing appropriate free weight exercises, since it's hard to figure out a person's postural imbalances when they are in a leg press machine! I also worry about the ab/adductor, lumbar and abdominal machines as far as safety is concerned. I want to give my clients the best workouts according to their needs while working under the studio's constraints and not insulting or undermining my employer. Is this method worthwhile for people who are already very active or people who have never exercised and are too busy/intimidated to join a gym?
To answer the question posed in your first paragraph, the answer is "most likely." Muscle hypertrophy will occur with any UN-accustomed stimulus to a certain degree. In other words, regardless of the programs acute variables (fast, slow), if your client is not accustomed to the stimulus, the body will be forced to adapt. The degree at which they adapt will depend on many factors – to name a few, the exact physiological stimulus, genetics, nutritive status, training age, current level of function, etc. My concern with this training variable is WHY? What is the functional purpose? What are the PERSON'S goals? Why “anchor” to a protocol – why not design an individualized program based on a CLIENT'S goals, not a pre-designed acute variable system?
In regards to your second paragraph, again, I would base what you do on the client. It sounds like you’re in a tough position. You’re stuck following a protocol as opposed to an individualized program (which is what clients are expecting). Personally, I would only perform what the client’s goals, wants and NEEDS dictate - NOT a protocol driven model.
I realize your position is hard, but you’ll never lose if you can explain why you are doing what you’re doing! Remember, what makes a great trainer great is NOT what is different about their approach but what he or she shares in common with the client's needs. In the end, there is nothing unique about being unique, because the power is not in what is unique but in what is common – common for the client!
Stick to your client's needs and you’ll do great! Good luck.