Isolation exercises? You can do well without them
Bodybuilders and other strength athletes with a respectable training volume don't need isolation exercises like biceps curls, triceps extensions and leg extensions. The added value of these exercises is zero. Brazilian sports scientists come to this conclusiio in a study that has been publshed in Sports. The Brazilians experimented with 17 trained young women.
The Brazilians divided 17 young women, who had been strength training for at least a year, into 2 groups. One group trained 6 days a week, and only did multi-joint exercises [MJ group], the second group did exactly the same as the first group - but added a few single-joint exercises to the schedule [MJ + SJ group].
The experiment lasted 8 weeks. Before and after that period, the researchers determined the women's strength and body composition.
The addition of the single-joint exercises to the training routines did not add anything. For example, the women in the MJ + SJ group did biceps curls, the women in the MJ group did not. Both groups, however, became equally much stronger at curling. Moreover, arm size increased equally in both groups.
"Based on the present findings, we conclude that the use of single joint exercises as a complement to a resistance training program containing multi joint exercises brings no additional benefit to trained women in terms of muscle performance and anthropometry", write the Brazilians.
"In light of this, we suggest that the use of resistance training program containing only multi joint exercises might be recommended with the purpose to provide a time efficient approach with no impairment in strength endurance or anthropometric measurements."
Sports (Basel). 2018 Nov 28;6(4).
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