When it comes to resistance training, negativity is actually a good thing.
Now this isn’t a license to have a bad attitude; we’re talking about the “negative” portion of each lift.
Concentric movements involve shortening the length of the muscle. Think of what happens when you perform a biceps curl. As the weight moves from your side towards your shoulder, the muscles on the front of your arm contract to form a compact ball. This is the phase of an exercise that most people focus on.
However, there’s another phase of each lift that’s also very important called the eccentric (or negative). Using our biceps curl example, the eccentric phase occurs when the muscles lengthen as the arm is lowered back down into the starting position at the side of the body.
The eccentric portion at the end of one repetition plays a key role in the concentric phase of the beginning of the repetition that immediately follows. Since the early portion of the concentric phase is a common sticking point (think about where you commonly get stuck as you attempt to increase the weight on the curl bar), building eccentric strength can be instrumental in breaking through plateaus.
Research also suggests that combining concentric and eccentric resistance training is synergistic. When combined, the rate of muscle hypertrophy is far more effective than when one phase is omitted or the two types of training are performed separately.
THE TAKE AWAY: Rather than just letting gravity take over after completing the concentric phase, slow the weight down and focus on the eccentric portion of each repetition. Lifting is one instance where there’s a real positive in being negative.