Developing muscle can be challenging for people to do. There are three types of muscle contractions:
1. Eccentric Contractions- A contraction that increases tension on the muscle as it lengthens. Example: Downward phase of the bicep curls.
2. Concentric Contractions-A contraction that shortens the muscle as tension is applied. Example: Upward phase of a bicep curl.
3. Isometric Contractions-Applying tension to the muscle without movement of the joint. Example: Holding a squat in the same position for a certain time.
When it comes to training, how many of you focus on concentric contractions? Research has suggested that eccentric muscle actions produce 20–60% greater forces than concentric activities (Hollander 2007). I bet you did not know that when you are feeling sore from your workout, that is due to the eccentric movements.
There are two types of eccentric contractions:
1. Voluntary Eccentric Contractions-Let’s say you are performing the bench press and you have a weight where you can slowly lower the weight to your chest and then press up in a controlled manner.
2. Involuntary Eccentric Contractions-You are performing a bench press with a very heavy weight. It is too heavy and you cannot control the weight.
There is research that support the benefits eccentric strength exercises for sports that involve running, jumping and throwing. These types of movements involve the stretch shortening cycle. The stretch-shortening cycle is an active stretch (eccentric contraction) of a muscle followed by an immediate shortening (concentric contraction) of that same muscle (Hollander 2007). For example, when we break down the squat jump, the eccentric phase is when we are squatting down and as we move up fast that is due to the concentric phase.
Research has suggested that everyone should use eccentric training into their programs. The benefits of performing these types of exercises are that it can increase strength and hypertrophy. A recent study implemented weights that were 5-10% greater than the max weight that they could lift. If the person could squat 225 lbs 1 time, then they would add anywhere from 230-240 lbs. After doing this for 2 sessions, the people experienced significant improvements in strength and power. This study also stated that neural adaptations improved significantly from performing eccentric exercises compared to concentric exercises.
Can You Use Eccentric Training for Improving Your Rehab?
In a study done by Alfredson (1998), the purpose was to see how eccentric exercise can strengthen diseased tendons. Fifteen athletes with chronic Achilles tendinosis, three sets of 15 repetitions of bent knee and straight knee calf raises were performed, twice a day, seven days a week, over 12 weeks. Athletes were told to work through pain, only ceasing exercise if pain became disabling. Load was increased in 5-kg increments with the use of a backpack that carried the weight once exercise with bodyweight was pain free. All 15 athletes returned to pre-injury levels of activity. The results also showed that they had significant decreases in pain with significant increases in strength.
Some studies have looked at 8 weeks of unilateral eccentric-only training enhanced the strength of the trained limb and also improved the untrained or contralateral limb. You may think that this was due to muscle gain, but this was due to an increase in neural adaptations. This type of training can give excitement for individuals with an immobilized limb that has been injured or operated on and the efficacy of eccentric training to enhance muscular fitness benefits to the impaired limb (Brandenburg 2002).
What Type of Eccentric Strength Technique Can You Do?
2/1 Technique
The 2/1 technique is designed for the person to lift in the concentric phase with 2 limbs and then 1 limb in the concentric phase. For example, you are performing a single leg squat, on the downward phase you squat with one leg and the upward phase you use 2 legs. You want to use a heavy weight that you can perform 5 reps and on the eccentric phase tempo should be about 5 secs. If you are a beginner, then this type of training might be something to work up to.
Slow Tempo
This type of training is pretty simple. You are going to grab a moderate weight that you can do 10 reps. Lets say we are doing the bench press with 135 lbs. When you take the weight off the rack, you are going to lower the weight for a 10 second count until it touches your chest and then press up as fast as you can. If you choose to do a heavier weight, the tempo could range from 5-8 seconds.
Negative Sets
Negative sets are like slow tempo sets, but the difference is that it only involves the eccentric phase. When performing the bench press, you are going to use a weight that is 10 lbs or greater. You will need 1-2 spotters (depending on how heavy the weight that you are using). You are going to take the weight off the rack, and then lower the weight as slow as you possibly can for 8-12 seconds. Then your spotters are going to lift back up to the top for you and then you repeat. It is recommended to start conservatively with this technique, as it places a large demand on the nervous system and therefore can elicit rapid periods of overreaching and potentially overtraining (Hollander 2007).
At COR, we have implemented eccentric bicep curls and hamstring curls with our boot campers. We chose these exercises because they are like each other. What we are doing is having them resist a heavy force while straightening the arm or leg. After the first time we did this, can you guess how they were feeling? They were experiencing some pretty good soreness. You may be thinking, is this due to the weakness of the muscle or could this be due to experiencing a new exercise? This is a question that we need to ask yourself as a coach. Make sure when you are doing this type of training that you give your body time to recover. It is important to do this because our nervous system is getting worked very hard and we do not want to overtrain you or your athletes.
Reference:
- Brandenburg JP, Docherty D. The effects of accentuated eccentric loading on strength, muscle hypertrophy, and neural adaptations in trained individuals. J Strength Cond Res 16: 25–32, 2002.
- Burd NA, West DW, Staples AW, Atherton PJ, Baker JM, Moore DR, Holwerda AM, Parise G, Rennie MJ, Baker SK, Phillips SM. Low-load high volume resistance exercise stimulates muscle protein synthesis more than high-load low volume resistance exercise in young men. PLoS One 5: e12033, 2010.
- Alfredson H, Pietilä T, Jonsson P, Lorentzon R. Heavy-load eccentric calf muscle training for treatment of chronic Achilles tendinosis. Am J Sports Med 1998;26(3):360-366.
- Hollander DB, Kraemer RR, Kilpatrick MW, Ramadan ZG, Reeves GV, Francois M, Hebert EP, Tryniecki JL. Maximal eccentric and concentric strength discrepancies between young men and women for dynamic resistance exercise. J Strength Cond Res 21: 34–40, 2007.
Written by Chris Barber, CPT