Michael GündillHow to Get the Most Mass and Strength From Explosive Training Part 2
Last month I discussed how and why most top bodybuilders train explosively. Their muscles respond best to fast contractions because they’re mainly endowed with fast, type 2 fibers. Champions also lower their weights very fast, but we’re constantly told to slow down our reps, especially on the negative, or eccentric, stroke. Well, my contention is that fast negatives are better for mass than slow negatives.
Explosive training is not perfect. Because the repetitions are fast, time under tension is very short, but we can solve that problem.
Are Negatives Overrated?
The eccentric phase of a repetition is supposed to be the most important part of the exercise—lowering the weight being more traumatic than actually lifting it. That means the negative should stimulate more growth.
Most of the studies conducted with eccentric training, however, used untrained subjects. They show that negatives are more traumatic than concentric reps. That’s predictable, as sedentary subjects rarely use their muscles, especially in a negative fashion. Because negative work is so new to their bodies, the untrained subjects get profound trauma from that style of training—and the trauma translates into fiber remodeling and growth.
Studies also demonstrate, though, that once a single workout is performed in a negative fashion, it’s very hard to replicate that growth response with another workout. That’s called the second-bout effect, an immunization against growth that lasts at least six months.1
So, while negatives are important, the more experienced you are, the more they lose their value as direct growth stimulators.
The Two Main Roles of Negatives
If I ask you to jump as high as possible, what do you do? You squat down a little before jumping up. Why do you go down when your goal is to go up as high as possible? In other words, why do you perform a short negative before your positive effort? To hypertrophy your muscles? No.
You go down simply because that short eccentric movement helps your muscles produce a much greater force of contraction. Try to jump from a seated position. Without a prestretch your muscles are pretty weak.
The eccentric part of an exercise has a twofold purpose:
1) Storing elastic energy. A muscle is like an elastic band. The more you stretch it, the more explosive the shortening is when you release it. It’s exactly the same for your muscles. Whenever you stretch them, they store energy, a.k.a. force, which is released during the ensuing contraction, and the extra involuntary force is added to your voluntary strength.
2) Triggering the myotatic reflex. The faster the stretch is, the more powerfully muscles react to it. A violent stretch “scares” the nervous system. As a result, unconscious reflexes force the muscles to contract in order to stop a potentially dangerous stretch. That’s called the myotatic reflex, and it’s an involuntary contraction.
So the main purpose of a negative is to add as much involuntary strength as possible to your voluntary force in order to create a more explosive effort.
What Do the Scientific Studies Show?
1) Fast negatives are more traumatic. Sedentary subjects trained one biceps in an eccentric fashion.2 They performed the negatives either fast (half a second) or slow (two seconds). Here’s what fast negatives induced:
• A greater loss of strength.
• More soreness.
• A 450 percent greater release of creatine kinase, a blood marker measuring muscle trauma.
• A need for prolonged recovery in between workouts.
Immunization against growth will not be as significant with fast eccentrics as with slow ones.
2) Fast negatives alter the composition of muscle fibers. In another, similar study, sedentary subjects trained one of their biceps in an eccentric fashion for 10 weeks.3 They performed either fast (less than half a second) or slow (two seconds) negatives. Muscle performance improved the most with fast reps. With slow eccentrics the subjects all reached a plateau after only five weeks of training, a consequence of the second-bout effect. Fast negatives overcome that limitation.