Strength training – a few explanations (Concentric, Eccentric and Isometric).
I remember when I first decided to write a blog – it was mainly down to wanting a revision tool for myself whilst studying, but also to help explain a lot of what is said and done in S&C to people who speak in more layman’s terms then the professional standard. This hit home the other night when I was talking to a friend about training strength twice a week – I sent him a link from William Wayland’s latest blog (I urge you all to read, digest and follow his blog – I do and to this day and after 3 years as an undergraduate still learn a hell of lot from what he says/shares) and after texting him he was although more knowledgeable, also unsure of some terminology used. Oh before I go further this is in NO WAY a dig at Powering Through (William Wayland) but more to point, that my blog was aimed to be more basic friendly and not indsutry savy. Whilst blogs like powering through contain far more useful content than this site – it can at times, especially to the uneducated be a little ‘heavy’.
So I decided to do a few blogs to explain things that are commonly read and quite commonly misunderstood. Given what we are looking to do (lift heavy weights – sometimes above our heads) it is quite important that we fully understand the concepts that we are looking to follow/adapt to our needs. I wasn’t too sure where to start with this, as it’s quite an expansive goal – do I explain sets, reps etc. Or do I go into muscle stretch-shortening cycle? Well I spoke to a few friends and shown them a few blogs, from a slightly subjective slant it was agreed that somethings are pretty much common knowledge i.e. sets, reps, KG’s, lbs and so on…
What they did say however was – what exactly is concentric, eccentric and isometric (again in light of the blog I pointed them too) so it made sense to start there. All 3 play an important part in strength training, research however has placed greater emphasis on certain parts of a push/pull exercise and these should make sense after reading this blog. Some trainers have their own philosophies on training and at times that can influence the way they coach but I feel what I explain below is widely agreed. So here goes:
For the sake of clarity and simplicity I am going to use a Squat exercise during explanation!
Eccentric (also known as Negative): The ececntric phase of an exercise is the strongest part of your squat – if we think about this logically, we can hold more weight during the down (eccentric) phase of a squat than the up phase. In essence what is happening during the eccentric phase of the squat is the muscles are lengthening. If it was a bicep curl it would be the down part of the curl or the lowering part of a bench press.
Concentric (also known as dynamic): Now that I have explained the eccentric phase of an exercise the concentric phase is pretty self-explanatory. The lift of a squat, the bringing up of a bi curl and up phase of a bench press. If eccentric is the lengthening of a muscle then concentric is the shortening of a muscle.
Isometric (also known as static): Is neither of the above (obviously) but literally is neither, the muscle is contracted and isn’t shortening or lengthening, what is also important is that there is NO joint movement – an exercise that springs to mind is plank.
The above to many may be simple known text, but there are some who don’t know this stuff and I hope this simple explanation has helped you. So when you’re next listening/reading something from an S&C person and they’re talking like the above you should be able to relate to what they are saying as opposed to just nodding and agreeing.
Next blog I imagine will look at other terminologies that are commonly seen, who knows where after that :)
Ooosss