If muscle growth is your main interest, focusing on eccentric contractions or training the muscle at long muscle lengths seems critical. Concentric contractions are still important, just of lesser importance than eccentric contractions.
ECCENTRIC OVERLOAD CAUSES MORE MUSCLE GROWTH WITH LESS VOLUME SUMMARY
- A recent study found that eccentric overload result in more muscle growth with less sets.
- Despite more than double the training volume for the concentric and eccentric contraction group, muscle growth was the same for the concentric and eccentric contractions group and the eccentric-only group.
CONCENTRIC VS ECCENTRIC HYPERTROPHY TRAINING
Over the last year, it has become clear that training at long muscle lengths or emphasizing the eccentric portion of the contraction is important for muscle growth. The latest research from Sato et al. has further emphasized the importance of eccentric exercise for muscle growth. Previous research has found that training at long muscle lengths can cause similar or even greater increases in muscle growth compared to those training with a full range of motion. (1, 2)
A 1991 study comparing concentric and eccentric contractions to concentric contractions alone found that the group performing concentric and eccentric contractions performed half the sets of the concentric-only group, yet greater increases in muscle growth. Average fiber area size increased by 25% in the concentric and eccentric group and 20% in the group that performed concentric-only exercises. (3)
ECCENTRIC LOADING WITH LESS VOLUME
The newest study by Sato has replicated the findings of earlier studies, showing that the eccentric portion of the exercise or training at long muscle lengths is crucial for muscle growth. (4) The researchers had 53 untrained men and women divided into four groups: 1.) Concentric and Eccentric contractions 2.) Concentric-only contractions 3.) Eccentric only contractions, and 4.) A control group.
Training intensity was gradually increased over the five-week study. The untrained subjects performed three sets of ten repetitions. The group that performed the concentric and eccentric contraction performed 60 contractions (i.e., greater volume) or double the contractions compared to the groups that performed either concentric or eccentric-only contractions (i.e., 30 contractions).
At the end of the five-week study, the training volume of the concentric and eccentric group was higher than the concentric and eccentric-only contractions group. The concentric and eccentric group average training volume was 5,745 compared to 2930 for the eccentric-only group and 3035 for the concentric-only group.
Despite more than double the training volume for the concentric and eccentric contraction group, muscle growth was the same for the concentric and eccentric contractions group and the eccentric-only group. Despite doing the same number of contractions as the eccentric-only group, the concentric-only group resulted in small changes in muscle growth. The concentric-only group resulted in roughly 75% less increases in muscle growth. This research suggests that eccentric contractions or training at long muscle lengths are essential for optimal increases in muscle growth.