This meta-analysis explored how shorter and longer eccentric phase durations influence hypertrophy, jump performance, and maximal strength. Shorter eccentrics enhanced jump performance, while longer eccentrics produced similar or greater strength gains in trained participants when volume was matched. Interestingly, the hypertrophy outcomes were unaffected. The full picture is more nuanced, so let’s unpack the findings.
Overview
- What did they test? Researchers conducted a systematic review and meta-analysis of training studies comparing different eccentric phase durations on strength, power, and hypertrophy outcomes. They also examined whether factors such as training status, exercise type, and volume matching influenced the results.
- What did they find? From 3,227 articles initially identified, 10 met the inclusion criteria, representing nine unique studies. Shorter eccentric durations enhanced jumping performance, while longer durations produced similar or greater maximal strength gains in trained individuals when volume-load was matched. Hypertrophy outcomes were comparable between approaches.
- What does it mean for you? If your goal is to enhance power, avoid extending the eccentric phase unnecessarily. For strength or hypertrophy, longer eccentrics are unlikely to make a meaningful difference, so choose a tempo that suits your preference and training style. Keep in mind that these conclusions are drawn from a limited number of studies, so further research may refine these recommendations.
What’s The Problem?
Muscles can contract and produce force in three ways: concentric, eccentric, and isometric. Most of the time, when we think of a “muscle contraction”, we’re thinking of a concentric action — the lifting phase of a movement, such as curling a barbell upward. But when we lower that barbell under control, our muscles are still contracting, this time eccentrically. An isometric contraction, on the other hand, occurs when the muscle produces force without changing length, like holding the barbell still with elbows bent at 90 degrees.
So, as you can see, during a typical resistance training exercise, all three contraction types are likely to occur at some point. Concentric actions shorten the muscle while producing force, eccentric actions lengthen it while producing force, and isometric actions maintain a fixed muscle length under tension.
While training variables like load, reps, and sets are often the focus of attention, the type of contraction — and the time spent in each phase — may also shape training outcomes. This meta-analysis specifically examined how altering the duration of the eccentric phase influences strength, hypertrophy, and power.
Purpose
The aim of this study was to quantitatively examine how training with different eccentric phase durations influences muscular performance — specifically strength and power — and hypertrophy outcomes.
Hypothesis
No hypothesis was specifically stated by the authors.
