Mixed
Maximal muscle lengthening (eccentric) contractions induce a more rapid rate of myofibrillar protein synthesis compared to maximal shortening (concentric) contractions when total mechanical work is matched.
To maximize muscle growth potential per unit of work, prioritize eccentric (lengthening) movements in your resistance training. While both concentric and eccentric exercises build muscle, eccentric actions trigger a faster and potentially greater anabolic response in the muscle fibers, provided you are training at high intensities.
Prior exercise elevated MPS above rest in both conditions, but there was a more rapid rise after LC (P < 0.01).
Why this rating
Randomized crossover design with healthy young men, but small sample size (n=8) and short duration (8.5h).
Source
Myofibrillar and collagen protein synthesis in human skeletal muscle in young men after maximal shortening and lengthening contractions
Daniel R. Moore et al. · American Journal of Physiology-Endocrinology and Metabolism · 2004
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