Is controlled release of muscle contraction more beneficial than free release?

Question

I used to think that best way to train a muscle is to do reps very slowly, but from the ACSM's manual I learned that it is a myth. Now that made me wonder about controlled release of muscle contraction (the latter half of a repetition). i.e. lowering your body down in controlled manner in a pullup/chinup, lowering the dumbell in a controlled way in dumbbell curls, for example.

Is controlled release of muscle contraction more beneficial (what ever your training goal may be) than free release? If it is beneficial, how beneficial would it be? Because, there will be a trade off between no. of reps & this controlled release technique. I mean for any weight training exercise, you'll be able to perform less no. of reps if you are doing this controlled release thing.

Answer 1

Eccentric (lengthening of a muscle) causes strength increases, but if it was more valuable than the concentric (tightening) activities people would just sit around doing negatives all day and then show up and bench 1000lbs without ever having pushed the bar off their chest before: it's ridiculous.

I'd answer your question by saying that there are three ways that eccentric exercises have a clear place:

• Doing pullups. For some folks who can't do a single pullup, doing negatives is a great way to accustomed yourself to the movement and build some strength.
• Not dropping like a stone and putting a tremendous amount of shock load on your body. Completely releasing your muscle tension at the top of a pullup, as an example, will cause severely damaging load to your joints and connective tissues. You need to have concentrated eccentric movements there to make your pullup downward movement controlled and safe.
• Sometimes the eccentric load is really desired like in the bottom of a squat which can give you a bit of a bounce.

There are other areas where although not primarily an eccentric movement, there's a large eccentric component (ie: skull crushers and good mornings) where eccentric lengthening (and DOMS) is just going to be part of the movement.

But barring those types of examples, I don't see why you'd purposefully rob yourself of pushing more weight by "training" your eccentric abilities more than are required for successfully performing the exercise.

Answer 2

The eccentric phase of a lift is classically part of mass gaining but there are other practices which skip almost all eccentric training and produce large mass gain. One group are Olympic Weightlifters, who drop the majority of their lifts. They do not lack for mass! http://assets1.tribesports.com/system/challenges/images/000/035/655/original/20130128140347-klokov-complex-50kg.jpg Another practice is the eccentric-less extra workouts done by Westside styles powerlifters. Skipping the eccentric phase can allow more total work done b/c as noted above, it is the most damaging. For one take on how concentric-only has produced great mass (and strength!!!!!!!!) gains, here is a take from Glenn Pendlay, training of many of America's best weightlifters: http://bastardolifters.blogspot.com/2010/03/mass-gain-theory-by-glenn-pendlay.html

Answer 3

What you say about the release of muscle contraction is called eccentric contraction. It is proved that when controlling this eccentric contraction is when more miofibrills are damaged and as we know, this is what we want to achieve to get the muscle gain.

Also, as @Peter says, when doing the eccentric contraction slowly (between 2-4 seconds) you increment the time under tension of the exercise and this is one of the factors that boost the hypertrophy effect.