A Edith Cowan University research (United States) has shown that a type of muscle contraction is the most effective for increasing muscle strength and size, and that instead of lifting weights, you have to emphasize downloading them.
The team, which also included researchers from Niigata University and Nishi Kyushu University (Japan), and Londrina State University (Brazil), had groups of people carry out three different types of dumbbell curl exercises and measured the results.
It was found that those they just lost weight they experienced the same improvements than those who raised and lowered the weight, despite performing only half as many repetitions.
“We already know that a single eccentric muscle contraction per day can increase muscle strength if it is done five days a weekbut concentric (lifting a weight) or isometric (holding a weight) muscle contraction does not provide such an effect“, commented one of the leaders of the investigation, Ken Nosaka.
Thus, this study shows that you can be much more efficient in the time you spend exercising and still see resignificant results If you focus the exercise on the eccentric muscle contractions.
Concentric muscle contractions contributed little to training effects.”
“In the case of a dumbbell curl, many people may believe that the lifting action provides the most benefit, or at least some benefit, but we found that concentric muscle contractions contributed little to the effects training”, the researcher has detailed.
The study consisted of three groups performing dumbbell curls twice a week for five weeks, plus a control group that did nothing.
Of the training groups, one performed only eccentric muscle contractions (lowering weight), other only concentric muscle contractions (lifting the weight) and another performed concentric and eccentric muscle contractions (lifting and lowering the weight alternately).
All three saw improvements in concentric strength, but that was the only improvement for the concentric-only group. The eccentric-only and concentric-eccentric groups also saw significant improvements in isometric strength (static) and in the eccentric force.
What is most interesting is that, even though the eccentric-only group did half as many reps as those who lifted and lowered weights, strength gains were very similar and the eccentric-only group also saw a higher improvement in muscle thicknessan indicator of muscle hypertrophy: 7.2% compared to 5.4% in the concentric and eccentric group.
“Understanding the benefits of eccentric training can allow people to spend their time on exercise more efficiently. With the small amount of daily exercise needed to see results, people don’t even have to go to the gym – they can incorporate eccentric exercise into their daily routine.”
Exercises to put it into practice
With a dumbbell, the teacher recommends use both hands to assist in the concentric phase (lifting the weight), before using one arm for the eccentric phase (lowering the weight), when performing biceps curls, overhead extension, front raise and shoulder press.
On leg weight machines, Professor Nosaka recommends using the same concentric/eccentric technique when performing knee extensions, leg curls, and calf raises.
Also at home
Nosaka assures that no gym weights needed to apply the same principles to a workout and has devised several simple exercises that can be done at home.
In the exercises, you feel the contracting muscles stretch gradually from the beginning to the end of the range of motion.
After each eccentric muscle contraction, minimize effort to return to the starting position (ie concentric muscle contraction). Then you have to repeat 10 times each exercise.
From a half squat position, recommends sitting slowly in a chair within three seconds, (narrower and wider stances will create different effects). “If it’s easy for you, try sitting on one leg,” she advises.
other exercise is the chair recline: “Sit at the front of a chair to make a space between your back and the backrest, lean back slowly in three seconds (arms can be crossed on the chest or held behind the head).”
The uneven squat is another of Nosaka’s proposals: “Stand behind a chair, lean to the side to put more weight on one leg, and then squat down in three seconds.”
To do heel down exercisehere are the tips: “Still behind a chair, lean forward and lift your heels. Then lift one leg off the ground and lower the heel of the other in three seconds.”
Afterwards, you have to lean against a wall with both arms fully extended. “Bend your elbow joint slowly for three seconds until your face is close to the wall,” explains the teacher.
Finally, it is found the front lunge: “Place one leg in front of the other and bend your knees deeper for three seconds.”