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Fitness Defined: Concentric and Eccentric Contractions (and Why It Matters)

By: , SparkPeople Blogger
2/26/2010 10:19 AM   :  78 comments   :  36,316 Views

Usually, the average exerciser doesn't think about physiology or kinesiology when he or she is exercising. Sure, you think about form, doing your exercises correctly, and achieving balance—both in terms of overall fitness (a balance of cardio, strength training and flexibility) and individual workouts (a balance in the body where you exercise all of your major muscle groups). And that's great! But there is also a lot going on in your body during each workout, and sometimes, learning more about exactly what is happening can help you work out more effectively so you can get better results.

Whether or not you've heard of concentric and eccentric muscle contractions, you can benefit from learning the difference—especially because focusing on ONE of them can help you get even better results from your strength training program—without spending more time in the gym.

Fitness Defined: Concentric and Eccentric Muscle Contractions (And Why It Matters)

Concentric (Positive) Contractions: Put simply, this contraction shortens your muscle as it acts against resistive force (like a weight). For example, during a biceps curl, the biceps contract concentrically during the lifting phase of the exercise.

Eccentric (Negative) Contractions: During these contractions, the muscles lengthen while producing force—usually by returning from a shortened (concentric) position to a resting position. Using the same example above, the lowering the weight back down during a biceps curl is an eccentric contraction for the biceps. Think of this as "putting on the breaks." You're basically slowing the descent of the weight back down instead of allowing the weight (and gravity) to just pull your arm back down passively.

So why does this matter?
It's a good idea to include both concentric and eccentric contractions in your strength-training program. Luckily, most traditional exercises include these movements—a lifting phase (using the shortening or concentric phase) and a lowering phase to return to the start position. However, how much time you spend in each phase can affect your results. Here are some facts:
  • Your muscles can generate more force during the eccentric phase of an exercise. For example, you may only be able to lift a 10-pound dumbbell for a biceps curl. But likely, you could hold and lower (the eccentric phase) a 15 or 20 pound weight.
  • By slowing down the negative (eccentric) phase of your exercise, you can help your muscles build greater strength. This is why, typically, people are advised to lower weights or return them to the start position slowly.
  • Negative training is a type of strength training designed for greater strength gains. It involves using heavier weights than you could typically lift concentrically and focusing just on the eccentric phase of the exercise. This does pose a higher risk for injury and should not be practiced by beginners, however.
  • You can also use negative training to your advantage—as a way to progress to exercises that are currently too difficult for you. For example, maybe you have a goal to perform real pull-ups but don't have the strength yet to lift yourself all the way up (concentric phase). You could help work up to that movement by focusing on the lowering phase. Stand on a box or step to come up to the "up" position and then work on slowly lowering yourself back down. After each lowering, step back up onto the box and repeat the lowering phase again. You'll be working the same muscles and still benefit from the exercise this way.
So next time you're in a class or following along with a DVD and the instructor tells you to lower the weights more slowly than you lifted them, you'll know that you're helping your muscles develop greater strength by doing so. And if you ever hit a plateau in your strength-training program focusing a little more on the negative part of your training can be just the ticket you need to make it to the next level.

Happy Lifting (and Lowering)!

Have you ever tried negative training? Will you think more about the eccentric phase of your exercises now that you know how much it can help you?


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Comments

  • 28
    Thanks Nicole! Great article, very informative. I new you were suppose to lower the weight slow and controlled to the starting position I just never knew why. - 2/27/2010   8:48:18 AM
  • 27
    Great article and appreciate the tip on the pull up. That is one of my goals this year to be able to do 10 pull ups. Now where did I put that box? - 2/27/2010   7:56:09 AM
  • 26
    Thank you for sharing! I remember learning this a long time ago while strength training but I almost talked myself out of it while observing other "healthier" people heaving the weights up and down at the gym with no eccentric focus whatsoever. Now I know! - 2/27/2010   6:27:12 AM
  • 25
    I used to be a member of a gym and did negative training. Then I injured myself while stretching, doing exactly what I was told - ruptured C7 disc. I never did return to weights after that because it took a couple years of healing before I was allowed. By then the gym had increased costs, the environment had changed and basically I do not like the place. I do wall push-ups which while isn't negative training per se, is lifting heavy (body weight) and slow. I know when I was using weights, I preferred the slower movements and heavier weights, sure was strong! - 2/27/2010   1:15:18 AM
  • 24
    Great tip on the pull-ups! I never thought about training for them that way. Perhaps this could work to strengthen sit-ups as well? - 2/27/2010   12:32:04 AM
  • 23
    I loved this article and will think about this as I practice it tomorrow. Thank you! - 2/26/2010   11:50:34 PM
  • 22
    Never heard of negative training before.....learn new things all the time at SP - 2/26/2010   10:46:41 PM
  • 21
    Great information!! - 2/26/2010   8:21:07 PM
  • 20
    Wonderful information; thank you. I have excellent triceps, fair biceps but still cannot even do one pull up without assistance!!! Why are they apparently so much more difficult for women then men? Is there that much muscle differentiation in the arms? - 2/26/2010   7:46:18 PM
  • 19
    I already knew that was the better way to do things, but I didn't know why. The description of how to do just the lowering phase of the pull-ups (and other exercises) to build up to doing real ones is very insightful and will be a great help as well! Thank you for this valuable information! :D (It would be nice to be able to bookmark/save this somehow!) - 2/26/2010   5:54:39 PM
  • 18
    Excellent information!! Thanks! - 2/26/2010   4:38:31 PM
  • JUHOEG
    17
    Great info - 2/26/2010   4:11:43 PM
  • 16
    I never knew, I'll have to give this a try. In my classes, our instructor goes so fast It's really difficult to keep up. Wonder if she knows this? Thanks for the info. - 2/26/2010   3:24:32 PM
  • LOGANSDRAMMAW
    15
    I am also interested in strength and core building so I will also give it a try. - 2/26/2010   2:48:53 PM
  • 14
    I try to use the 2 up & 4 down rule when I'm strength training. I feel like the results are good. Although, I'm no expert, so, what do I know? - 2/26/2010   2:39:38 PM
  • 13
    I've heard of this before, and done it, but now I'll try it with pull-ups too. Hopefully I too can get to an unassisted pull up some day. - 2/26/2010   2:08:57 PM
  • 12
    ChaLEAN Extreme focuses on this type of ST :) Previously, (talking hs & uni/ late 80s-early 90s) we were taught to do 3 sets of 12 reps -- quickly. 1-2-3...

    This was totally different for me and it is amazing. Amazing. I've never put on muscle like this using the "old" method, which now I understand is more for endurance, which is nice, too. :) - 2/26/2010   1:49:23 PM
  • 11
    When I had a personal trainer in high school for sports my trainer always did weights with me three times a week and teached me exactly this method of lifting. She would tell me..."Up for two counts but down for four". It worked and I was really lean and toned! I still use her advice now for my strength training and the best thing is you can apply it to free weights or machines! - 2/26/2010   1:34:10 PM
  • 10
    I wouldn't have learned to do unassisted pullups without negative training! - 2/26/2010   1:07:32 PM
  • 9
    Good to know its so beneficial, I've always tried to lower slower, focusing on getting just above the "tap" point of the weights on the machines before pulling/pushing up again. Patience and perseverance are your friends in weight training. - 2/26/2010   12:53:43 PM
  • 8
    Interesting! Thanks Nicole it's good food for thought! - 2/26/2010   12:31:02 PM
  • 7
    I progressed to toe pushups using negative training. It's a very exciting way to work out! - 2/26/2010   12:28:12 PM
  • 6
    in my strength training class we alternate- 1 up 3 down, 2 up 2 down or 3 up 1 down. It's a different pattern each class, and I think it works quite well. - 2/26/2010   12:23:48 PM
  • 5
    I have always concentrated more on the negative side and it has worked for me on the strenght gaining side of things. - 2/26/2010   12:17:40 PM
  • 4
    Very interesting ,I must try this next time I exercise. - 2/26/2010   12:13:44 PM
  • 3
    Sounds like something I'll try tomorrow when I do my strength routine. Very interesting. - 2/26/2010   12:07:45 PM
  • 2
    I am interested in gaining strength, especialy in my upper body. I'll give this a try. We usually use machines, sounds like this will work on machines too! Thanks! - 2/26/2010   11:45:10 AM

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