Super Slow Training

Question:

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?

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