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Definition: "An ergogenic aid is any substance or phenomenon that enhances performance "

26.11.2009

Muscle groups work harder during a set if you focus on them

In the gym there's no exercise that trains only the muscle group you want to stimulate. Other groups are always involved. That's why it's not so easy to achieve directed growth of particular parts of the body. If you have strong shoulders and weak chest muscles, it's pretty difficult to develop good pecs. Or is it not that difficult after all? Sports scientists at the University of South Carolina Upstate discovered a very simple method. Focus.

Study
The researchers describe in their article, which was published in the Journal of Strength and Conditioning Research, how they attached electrodes to the teres major [a muscle in your upper back, that runs over your shoulder blade], the biceps and the latissimus dorsi to their subjects. They then got the 8 women, aged between 18 and 35, to do lat pull-downs.

Results
The researchers recorded the electrical activity during two sets. The results are shown below.

The researchers then repeated the activity. First they got the women to perform one set. Then a trainer told the women that they should concentrate on getting the power for the movement out of their latissimus dorsi muscles. That was why they were doing lat pull-downs: to develop the broad upper back muscle.

The trainer explained to the women exactly where the lats are located, and touched the muscles in the women. Then the women performed another set. The figure below shows the electrical activity in the muscles.

Focussing your attention on a muscle group while performing a set increases the intensity with which your muscle takes part in the movement. Isolating muscles is a matter of good ol' fashioned focus & concentration.

Erm...
The researchers had the women train at 30 percent of their maximal strength. That's too light. Bodybuilders train at 60-85 percent of their maximum. The researchers don't know whether using focus to isolate a muscle group works as well at higher intensity.

Source:
J Strength Cond Res. 2009 Nov;23(8):2204-9.

More:
Increase your strength by watching your muscles at work 17.11.2009