Tuesday, January 10, 2012

Eccentric Contractions: Build a Better Body!

To build better bodies, many people take to the gym to do their workout, which consists of exercises for the chest, back, arms, abs, shoulders and legs. They do their typical three sets of 8-12 exercise for 45 minutes, three or four days per week, and then go home. If this is your consistent routine, then good job! You are staying strong, staying in decent shape, staying relatively healthy. They key word is staying. Are you happy with staying where you are? Or do you want to get better?

The Science

Typical weightlifting involves two types of contractions: concentric and eccentric. Generally, most lifters focus on the concentric contraction, where the muscle length shortens as the weight is lifted. The eccentric contraction is the downward motion of the weight, or the muscle lengthening action. In a bicep curl, the upward curling motion is the concentric, and the lowering motion is the eccentric contraction. Dr. Len Kravitz of the University of New Mexico conducted extensive research and found that emphasizing the eccentric contraction helps increase strength and size better than traditional weight lifting.

In "Eccentric Exercise: A Comprehensive Review of a Distinctive Training Method", Dr. Kravitz explains that eccentric muscle contractions are able to resist up to 20% more force than concentric contractions, allowing the muscle to achieve optimal gains faster. Traditional weightlifting rhythms consist of a two to three second concentric contraction, followed by a one second eccentric contraction. Dr. Kravitz suggests a typical concentric contraction, followed by a four to five second eccentric contraction.


Eccentric muscle contractions increase muscle size and strength better than concentric contractions due to increased force production and greater activation of muscle fiber cross-bridging. According to The National Strength and Conditioning Association, submaximal eccentric contractions do not cause muscle damage, but rather help strengthen the fibers to help protect against injury. Eccentric contractions are beneficial post injury during rehabilitation for this reason as well.


To take advantage of the greater force production, use a spotter and try a bench press. Find your one repetition maximum, or the heaviest weight you can lift just once. On a different day, allowing for recovery, add 5% of your maximum weight. For example, if your 1-rep max was 100 lbs. put 105lbs on the bar. Have a spotter help you press the bar up until your arms are straight. Slowly lower the bar for 5 seconds until it reaches your chest (but not touching your chest). Have the spotter help you back up and repeat this exercise about 8 times. If you do not have a spotter available, try benching on the Smith Machine. Put 50% of your 1-rep max on the bar, 50 lbs in our example. Press the bar up with both hands, then remove your left hand and control the bard down to your chest using only your right hand. Repeat for 8 repetitions and switch. You do not always have to lift over your 1-rep max to achieve results. In fact, beginners should start with a lighter weight. For example, load the lat pulldown with your 10-rep maximum. Lower the bar as usual to your chest, but take five seconds to lift it back up. See if you can still do 10-repetitions.


Do a total body eccentric workout once per week and watch your muslces develop and increase strenth. For the first week, use this technique with lat pulldown, dumbbell chest press, barbell biceps curls, triceps cable rope pulldown and crunches. For the second week, do barbbell bench press, seated cable row, dumbbell biceps hammer curls, overhead triceps extensions, and abdominal leg lifts. I can tell you from personal experience you will feel the results of eccentric contractions over the next few days with muscle soreness!


Eccentric contractions are associated with higher incidents of DOMS, or delayed onset muscle soreness. Because the muscle fibers are under more pressure, they experience more breakdowns during the workout. The best way to decrease muscle soreness is to warm-up with very light total-body eccentric contractions about a week before trying heavier-weight eccentric contractions. If you are a power or sprint athlete, eccentric contractions help increase your overall strength, but they can decrease power output since you are essentially training you body to be slow rather than fast. Use these considerations before incorporating eccentric workouts.

"Essentials of Strength Training and Conditioning"; National Strength and Conditioning Association; Baechel, Thomas R. and Earle, Roger W; 2008

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